If you've been in an airport, coffee shop, library or hotel recently, chances are you've been right in the middle of a wireless network. Many people also use wireless networking, also called WiFi or 802.11 networking, to connect their computers at home, and some cities are trying to use the technology to provide free or low-cost Internet access to residents. In the near future, wireless networking may become so widespread that you can access the Internet just about anywhere at any time, without using wires.
WiFi has a lot of advantages. Wireless networks are easy to set up and inexpensive. They're also unobtrusive -- unless you're on the lookout for a place to use your laptop, you may not even notice when you're in a hotspot. In this article, we'll look at the technology that allows information to travel over the air. We'll also review what it takes to create a wireless network in your home.
First, let's go over a few WiFi basics.
Saturday, June 30, 2012
Types of wireless networks
Types of wireless networks
Wireless PAN
Wireless personal area networks (WPANs) interconnect devices within a relatively small area, that is generally within a person's reach.[3] For example, both Bluetooth radio and invisible infrared light provides a WPAN for interconnecting a headset to a laptop. ZigBee also supports WPAN applications.[4] Wi-Fi PANs are becoming commonplace (2010) as equipment designers start to integrate Wi-Fi into a variety of consumer electronic devices. Intel "My WiFi" and Windows 7 "virtual Wi-Fi" capabilities have made Wi-Fi PANs simpler and easier to set up and configure.[5]
[edit]Wireless LAN
Main article: Wireless LAN
A wireless local area network (WLAN) links two or more devices over a short distance using a wireless distribution method, usually providing a connection through an access point for Internet access. The use of spread-spectrum or OFDM technologies may allow users to move around within a local coverage area, and still remain connected to the network.
Products using the IEEE 802.11 WLAN standards are marketed under the Wi-Fi brand name. Fixed wireless technology implements point-to-point links between computers or networks at two distant locations, often using dedicated microwave or modulated laser light beams over line of sight paths. It is often used in cities to connect networks in two or more buildings without installing a wired link.
[edit]Wireless mesh network
Main article: wireless mesh network
A wireless mesh network is a wireless network made up of radio nodes organized in a mesh topology. Each node forwards messages on behalf of the other nodes. Mesh networks can "self heal", automatically re-routing around a node that has lost power.
[edit]Wireless MAN
Wireless metropolitan area networks are a type of wireless network that connects several wireless LANs.
WiMAX is a type of Wireless MAN and is described by the IEEE 802.16 standard.[6]
[edit]Wireless WAN
Wireless wide area networks are wireless networks that typically cover large areas, such as between neighboring towns and cities, or city and suburb. These networks can be used to connect branch offices of business or as a public internet access system. The wireless connections between access points are usually point to point microwave links using parabolic dishes on the 2.4 GHz band, rather than omnidirectional antennas used with smaller networks. A typical system contains base station gateways, access points and wireless bridging relays. Other configurations are mesh systems where each access point acts as a relay also. When combined with renewable energy systems such as photo-voltaic solar panels or wind systems they can be stand alone systems.
[edit]Mobile devices networks
Further information: mobile telecommunications
With the development of smartphones, cellular telephone networks routinely carry data in addition to telephone conversations:
Global System for Mobile Communications (GSM): The GSM network is divided into three major systems: the switching system, the base station system, and the operation and support system. The cell phone connects to the base system station which then connects to the operation and support station; it then connects to the switching station where the call is transferred to where it needs to go. GSM is the most common standard and is used for a majority of cell phones.[7]
Personal Communications Service (PCS): PCS is a radio band that can be used by mobile phones in North America and South Asia. Sprint happened to be the first service to set up a PCS.
D-AMPS: Digital Advanced Mobile Phone Service, an upgraded version of AMPS, is being phased out due to advancement in technology. The newer GSM networks are replacing the older system.
[edit]Uses
Some examples of usage include cellular phones which are part of everyday wireless networks, allowing easy personal communications. Another example, Inter-continental network systems, use radio satellites to communicate across the world. Emergency services such as the police utilize wireless networks to communicate effectively as well. Individuals and businesses use wireless networks to send and share data rapidly, whether it be in a small office building or across the world.
[edit]General
In a general sense, wireless networks offer a vast variety of uses by both business and home users.[8]
"Now, the industry accepts a handful of different wireless technologies. Each wireless technology is defined by a standard that describes unique functions at both the Physical and the Data Link layers of the OSI Model. These standards differ in their specified signaling methods, geographic ranges, and frequency usages, among other things. Such differences can make certain technologies better suited to home networks and others better suited to network larger organizations."[8]
[edit]Performance
Each standard varies in geographical range, thus making one standard more ideal than the next depending on what it is one is trying to accomplish with a wireless network.[8] The performance of wireless networks satisfies a variety of applications such as voice and video. The use of this technology also gives room for future expansions. As wireless networking has become commonplace, sophistication increased through configuration of network hardware and software.[9]
[edit]Space
Space is another characteristic of wireless networking. Wireless networks offer many advantages when it comes to difficult-to-wire areas trying to communicate such as across a street or river, a warehouse on the other side of the premise or buildings that are physically separated but operate as one.[9] Wireless networks allow for users to designate a certain space which the network will be able to communicate with other devices through that network. Space is also created in homes as a result of eliminating clutters of wiring.[10] This techonology allows for an alternative to installing physical network mediums such as TPs, coaxes, or fiber-optics, which can also be expensive.
[edit]Home
For homeowners, wireless technology is an effective option as compared to ethernet for sharing printers, scanners, and high speed internet connections. WLANs help save from the cost of installation of cable mediums, save time from physical installation, and also creates mobility for devices connected to the network.[10] Wireless networks are simple and require as few as one single wireless access point connected directly to the Internet via a router.[8]
[edit]Environmental concerns
See also: Wireless electronic devices and health
Starting around 2009, there have been increased concerns about the safety of wireless communications, despite little evidence of health risks so far.[11] The president of Lakehead University refused to agree to installation of a wireless network citing a California Public Utilities Commission study which said that the possible risk of tumors and other diseases due to exposure to electromagnetic fields (EMFs) needs to be further investigated.[12]
Wireless access points are also often close to humans, but the drop off in power over distance is fast, following the inverse-square law.[13] The HPA's position is that “...radio frequency (RF) exposures from WiFi are likely to be lower than those from mobile phones.” It also saw “...no reason why schools and others should not use WiFi equipment.”[14] In October 2007, the HPA launched a new “systematic” study into the effects of WiFi networks on behalf of the UK government, in order to calm fears that had appeared in the media in a recent period up to that time".[15] Dr Michael Clark, of the HPA, says published research on mobile phones and masts does not add up to an indictment of WiFi.[16]
Wireless PAN
Wireless personal area networks (WPANs) interconnect devices within a relatively small area, that is generally within a person's reach.[3] For example, both Bluetooth radio and invisible infrared light provides a WPAN for interconnecting a headset to a laptop. ZigBee also supports WPAN applications.[4] Wi-Fi PANs are becoming commonplace (2010) as equipment designers start to integrate Wi-Fi into a variety of consumer electronic devices. Intel "My WiFi" and Windows 7 "virtual Wi-Fi" capabilities have made Wi-Fi PANs simpler and easier to set up and configure.[5]
[edit]Wireless LAN
Main article: Wireless LAN
A wireless local area network (WLAN) links two or more devices over a short distance using a wireless distribution method, usually providing a connection through an access point for Internet access. The use of spread-spectrum or OFDM technologies may allow users to move around within a local coverage area, and still remain connected to the network.
Products using the IEEE 802.11 WLAN standards are marketed under the Wi-Fi brand name. Fixed wireless technology implements point-to-point links between computers or networks at two distant locations, often using dedicated microwave or modulated laser light beams over line of sight paths. It is often used in cities to connect networks in two or more buildings without installing a wired link.
[edit]Wireless mesh network
Main article: wireless mesh network
A wireless mesh network is a wireless network made up of radio nodes organized in a mesh topology. Each node forwards messages on behalf of the other nodes. Mesh networks can "self heal", automatically re-routing around a node that has lost power.
[edit]Wireless MAN
Wireless metropolitan area networks are a type of wireless network that connects several wireless LANs.
WiMAX is a type of Wireless MAN and is described by the IEEE 802.16 standard.[6]
[edit]Wireless WAN
Wireless wide area networks are wireless networks that typically cover large areas, such as between neighboring towns and cities, or city and suburb. These networks can be used to connect branch offices of business or as a public internet access system. The wireless connections between access points are usually point to point microwave links using parabolic dishes on the 2.4 GHz band, rather than omnidirectional antennas used with smaller networks. A typical system contains base station gateways, access points and wireless bridging relays. Other configurations are mesh systems where each access point acts as a relay also. When combined with renewable energy systems such as photo-voltaic solar panels or wind systems they can be stand alone systems.
[edit]Mobile devices networks
Further information: mobile telecommunications
With the development of smartphones, cellular telephone networks routinely carry data in addition to telephone conversations:
Global System for Mobile Communications (GSM): The GSM network is divided into three major systems: the switching system, the base station system, and the operation and support system. The cell phone connects to the base system station which then connects to the operation and support station; it then connects to the switching station where the call is transferred to where it needs to go. GSM is the most common standard and is used for a majority of cell phones.[7]
Personal Communications Service (PCS): PCS is a radio band that can be used by mobile phones in North America and South Asia. Sprint happened to be the first service to set up a PCS.
D-AMPS: Digital Advanced Mobile Phone Service, an upgraded version of AMPS, is being phased out due to advancement in technology. The newer GSM networks are replacing the older system.
[edit]Uses
Some examples of usage include cellular phones which are part of everyday wireless networks, allowing easy personal communications. Another example, Inter-continental network systems, use radio satellites to communicate across the world. Emergency services such as the police utilize wireless networks to communicate effectively as well. Individuals and businesses use wireless networks to send and share data rapidly, whether it be in a small office building or across the world.
[edit]General
In a general sense, wireless networks offer a vast variety of uses by both business and home users.[8]
"Now, the industry accepts a handful of different wireless technologies. Each wireless technology is defined by a standard that describes unique functions at both the Physical and the Data Link layers of the OSI Model. These standards differ in their specified signaling methods, geographic ranges, and frequency usages, among other things. Such differences can make certain technologies better suited to home networks and others better suited to network larger organizations."[8]
[edit]Performance
Each standard varies in geographical range, thus making one standard more ideal than the next depending on what it is one is trying to accomplish with a wireless network.[8] The performance of wireless networks satisfies a variety of applications such as voice and video. The use of this technology also gives room for future expansions. As wireless networking has become commonplace, sophistication increased through configuration of network hardware and software.[9]
[edit]Space
Space is another characteristic of wireless networking. Wireless networks offer many advantages when it comes to difficult-to-wire areas trying to communicate such as across a street or river, a warehouse on the other side of the premise or buildings that are physically separated but operate as one.[9] Wireless networks allow for users to designate a certain space which the network will be able to communicate with other devices through that network. Space is also created in homes as a result of eliminating clutters of wiring.[10] This techonology allows for an alternative to installing physical network mediums such as TPs, coaxes, or fiber-optics, which can also be expensive.
[edit]Home
For homeowners, wireless technology is an effective option as compared to ethernet for sharing printers, scanners, and high speed internet connections. WLANs help save from the cost of installation of cable mediums, save time from physical installation, and also creates mobility for devices connected to the network.[10] Wireless networks are simple and require as few as one single wireless access point connected directly to the Internet via a router.[8]
[edit]Environmental concerns
See also: Wireless electronic devices and health
Starting around 2009, there have been increased concerns about the safety of wireless communications, despite little evidence of health risks so far.[11] The president of Lakehead University refused to agree to installation of a wireless network citing a California Public Utilities Commission study which said that the possible risk of tumors and other diseases due to exposure to electromagnetic fields (EMFs) needs to be further investigated.[12]
Wireless access points are also often close to humans, but the drop off in power over distance is fast, following the inverse-square law.[13] The HPA's position is that “...radio frequency (RF) exposures from WiFi are likely to be lower than those from mobile phones.” It also saw “...no reason why schools and others should not use WiFi equipment.”[14] In October 2007, the HPA launched a new “systematic” study into the effects of WiFi networks on behalf of the UK government, in order to calm fears that had appeared in the media in a recent period up to that time".[15] Dr Michael Clark, of the HPA, says published research on mobile phones and masts does not add up to an indictment of WiFi.[16]
Wireless network
Wireless network
Wireless network refers to any type of computer network that is not connected by cables of any kind. It is a method by which homes, telecommunications networks and enterprise (business) installations avoid the costly process of introducing cables into a building, or as a connection between various equipment locations.[1] Wireless telecommunications networks are generally implemented and administered using a transmission system called radio waves. This implementation takes place at the physical level (layer) of the OSI model network structure.[2]
Wireless network refers to any type of computer network that is not connected by cables of any kind. It is a method by which homes, telecommunications networks and enterprise (business) installations avoid the costly process of introducing cables into a building, or as a connection between various equipment locations.[1] Wireless telecommunications networks are generally implemented and administered using a transmission system called radio waves. This implementation takes place at the physical level (layer) of the OSI model network structure.[2]
Trail: Custom Networking
Trail: Custom Networking
The Java platform is highly regarded in part because of its suitability for writing programs that use and interact with the resources on the Internet and the World Wide Web. In fact, Java-compatible browsers use this ability of the Java platform to the extreme to transport and run applets over the Internet.
This trail walks you through the complexities of writing Java applications and applets that can be used on the Internet.
Overview of Networking has two sections. The first describes the networking capabilities of the Java platform that you may already be using without realizing that you are using the network. The second provides a brief overview of networking to familiarize you with terms and concepts that you should understand before reading how to use URLs, sockets, and datagrams.
Working With URLs discusses how your Java programs can use URLs to access information on the Internet. A URL (Uniform Resource Locator) is the address of a resource on the Internet. Your Java programs can use URLs to connect to and retrieve information over a network. This lesson provides a more complete definition of a URL and shows you how to create and parse a URL, how to open a connection to a URL, and how to read from and write to that connection.
All About Sockets explains how to use sockets so that your programs can communicate with other programs on the network. A socket is one endpoint of a two-way communication link between two programs running on the network. This lesson shows you how a client can connect to a standard server, the Echo server, and communicate with it via a socket. It then walks you through the details of a complete client/server example, which shows you how to implement both the client side and the server side of a client/server pair.
All About Datagrams takes you step by step through a simple client/server example that uses datagrams to communicate. It then challenges you to rewrite the example using multicast socket instead.
Programmatic Access to Network Parameters explains why you might want to access network interface parameters and how to do so. It gives examples of how to list all the IP addresses assigned to the machine as well as other useful information such as whether the interface is running.
Working With Cookies discusses how cookies are used to create a session between a client and server, and how you can take advantage of cookies in your HTTP URL connections.
Security considerations:
Note that communications over the network are subject to approval by the current security manager. The Security Manager describes what a security manager is and how it impacts your applications. For general information about the security features provided by the JDK, refer to Security Features in Java SE .
The example programs in the following lessons that cover URLs, sockets, and datagrams are standalone applications, which, by default, have no security manager. If you convert these applications to applets, they may be unable to communicate over the network, depending on the browser or viewer in which they are running. See What Applets Can and Cannot Do for information about the security restrictions placed on applets.
The Java platform is highly regarded in part because of its suitability for writing programs that use and interact with the resources on the Internet and the World Wide Web. In fact, Java-compatible browsers use this ability of the Java platform to the extreme to transport and run applets over the Internet.
This trail walks you through the complexities of writing Java applications and applets that can be used on the Internet.
Overview of Networking has two sections. The first describes the networking capabilities of the Java platform that you may already be using without realizing that you are using the network. The second provides a brief overview of networking to familiarize you with terms and concepts that you should understand before reading how to use URLs, sockets, and datagrams.
Working With URLs discusses how your Java programs can use URLs to access information on the Internet. A URL (Uniform Resource Locator) is the address of a resource on the Internet. Your Java programs can use URLs to connect to and retrieve information over a network. This lesson provides a more complete definition of a URL and shows you how to create and parse a URL, how to open a connection to a URL, and how to read from and write to that connection.
All About Sockets explains how to use sockets so that your programs can communicate with other programs on the network. A socket is one endpoint of a two-way communication link between two programs running on the network. This lesson shows you how a client can connect to a standard server, the Echo server, and communicate with it via a socket. It then walks you through the details of a complete client/server example, which shows you how to implement both the client side and the server side of a client/server pair.
All About Datagrams takes you step by step through a simple client/server example that uses datagrams to communicate. It then challenges you to rewrite the example using multicast socket instead.
Programmatic Access to Network Parameters explains why you might want to access network interface parameters and how to do so. It gives examples of how to list all the IP addresses assigned to the machine as well as other useful information such as whether the interface is running.
Working With Cookies discusses how cookies are used to create a session between a client and server, and how you can take advantage of cookies in your HTTP URL connections.
Security considerations:
Note that communications over the network are subject to approval by the current security manager. The Security Manager describes what a security manager is and how it impacts your applications. For general information about the security features provided by the JDK, refer to Security Features in Java SE .
The example programs in the following lessons that cover URLs, sockets, and datagrams are standalone applications, which, by default, have no security manager. If you convert these applications to applets, they may be unable to communicate over the network, depending on the browser or viewer in which they are running. See What Applets Can and Cannot Do for information about the security restrictions placed on applets.
Network Design
Computer networks also differ in their design. The two types of high-level network design are called client-server and peer-to-peer. Client-server networks feature centralized server computers that store email, Web pages, files and or applications. On a peer-to-peer network, conversely, all computers tend to support the same functions. Client-server networks are much more common in business and peer-to-peer networks much more common in homes.
A network topology represents its layout or structure from the point of view of data flow. In so-called bus networks, for example, all of the computers share and communicate across one common conduit, whereas in a star network, all data flows through one centralized device. Common types of network topologies include bus, star, ring and mesh.
Network Protocols
In networking, the communication language used by computer devices is called the protocol. Yet another way to classify computer networks is by the set of protocols they support. Networks often implement multiple protocols to support specific applications. Popular protocols include TCP/IP, the most common protocol found on the Internet and in home networks.
Wired vs Wireless Networking
Many of the same network protocols, like TCP/IP, work in both wired and wireless networks. Networks with Ethernet cables predominated in businesses, schools, and homes for several decades. Recently, however, wireless networking alternatives have emerged as the premier technology for building new computer networks.
A network topology represents its layout or structure from the point of view of data flow. In so-called bus networks, for example, all of the computers share and communicate across one common conduit, whereas in a star network, all data flows through one centralized device. Common types of network topologies include bus, star, ring and mesh.
Network Protocols
In networking, the communication language used by computer devices is called the protocol. Yet another way to classify computer networks is by the set of protocols they support. Networks often implement multiple protocols to support specific applications. Popular protocols include TCP/IP, the most common protocol found on the Internet and in home networks.
Wired vs Wireless Networking
Many of the same network protocols, like TCP/IP, work in both wired and wireless networks. Networks with Ethernet cables predominated in businesses, schools, and homes for several decades. Recently, however, wireless networking alternatives have emerged as the premier technology for building new computer networks.
What is (Wireless / Computer) Networking?
What is (Wireless / Computer) Networking?
Question: What is (Wireless / Computer) Networking?
Answer: In the world of computers, networking is the practice of linking two or more computing devices together for the purpose of sharing data. Networks are built with a mix of computer hardware and computer software.
Question: What is (Wireless / Computer) Networking?
Answer: In the world of computers, networking is the practice of linking two or more computing devices together for the purpose of sharing data. Networks are built with a mix of computer hardware and computer software.
Communications
Communications
Communication Studies are often considered a part of both the social sciences and the humanities, drawing heavily on fields such as sociology, psychology, anthropology, information science, biology, political science, and economics as well as rhetoric, literary studies, and semiotics. Many communications concepts describe the transfer of information from one source to another, and can thus be conceived of in terms of a network.
[edit]Community
In J.A. Barnes' day, a "community" referred to a specific geographic location and studies of community ties had to do with who talked, associated, traded, and attended church with whom. Today, however, there are extended "online" communities developed through telecommunications devices and social network services. Such devices and services require extensive and ongoing maintenance and analysis, often using network science methods. Community development studies, today, also make extensive use of such methods.
[edit]Complex Networks
Complex networks require methods specific to modelling and interpreting social complexity and complex adaptive systems, including techniques of dynamic network analysis.
[edit]Criminal networks
In criminology and urban sociology, much attention has been paid to the social networks among criminal actors. For example, Andrew Papachristos[citation needed] has studied gang murders as a series of exchanges between gangs. Murders can be seen to diffuse outwards from a single source, because weaker gangs cannot afford to kill members of stronger gangs in retaliation, but must commit other violent acts to maintain their reputation for strength.
[edit]Diffusion of innovations
Diffusion of ideas and innovations studies focus on the spread and use of ideas from one actor to another or one culture and another. This line of research seeks to explain why some become "early adopters" of ideas and innovations, and links social network structure with facilitating or impeding the spread of an innovation.
[edit]Demography
In demography, the study of social networks has led to new sampling methods for estimating and reaching populations that are hard to enumerate (for example, homeless people or intravenous drug users.) For example, respondent driven sampling is a network-based sampling technique that relies on respondents to a survey recommending further respondents.
[edit]Economic sociology
The field of sociology focuses almost entirely on networks of outcomes of social interactions. More narrowly, economic sociology considers behavioral interactions of individuals and groups through social capital and social "markets". Sociologists, such as Mark Granovetter, have developed core principles about the interactions of social structure, information, ability to punish or reward, and trust that frequently recur in their analyses of political, economic and other institutions. Granovetter examines how social structures and social networks can affect economic outcomes like hiring, price, productivity and innovation and describes sociologists’ contributions to analyzing the impact of social structure and networks on the economy.[47]
[edit]Health care
Analysis of social networks is increasingly incorporated into heath care analytics, not only in epidemological studies but also in models of patient communication and education, disease prevention, mental health diagnosis and treatment, and in the study of health care organizations and systems.[48]
[edit]Human ecology
Human ecology is an interdisciplinary and transdisciplinary study of the relationship between humans and their natural, social, and built environments. The scientific philosophy of human ecology has a diffuse history with connections to geography, sociology, psychology, anthropology, zoology, and natural ecology.[49][50]
[edit]Language/Linguistics
Studies of language and lingustics, particularly evolutionary linguistics, focus on the development of linguistic forms and transfer of changes, sounds or words, from one language system to another through networks of social interaction. Social networks are also important in language shift, as groups of people add and/or abandon languages to their repertoire.
[edit]Organizational Studies
Research studies of formal or informal organizational relationships, organizational communication, economics, economic sociology, and other resource transfers. Social networks have also been used to examine how organizations interact with each other, characterizing the many informal connections that link executives together, as well as associations and connections between individual employees at different organizations [51]. Intra-organizational networks have been found to affect organizational commitment [52], organizational identification [37], interpersonal citizenship behaviour.[53]
[edit]Social capital
Social capital is a sociological concept which refers to the value of social relations and the role of cooperation and confidence to achieve positive outcomes. The term refers to the value one can get from their social ties. For example, newly arrived immigrants can make use of their social ties to established migrants to acquire jobs they may otherwise have trouble getting (e.g., because of lack of knowledge of language). Studies show that there a positive relationship between social capital and the intensity of social network use.[54]
Communication Studies are often considered a part of both the social sciences and the humanities, drawing heavily on fields such as sociology, psychology, anthropology, information science, biology, political science, and economics as well as rhetoric, literary studies, and semiotics. Many communications concepts describe the transfer of information from one source to another, and can thus be conceived of in terms of a network.
[edit]Community
In J.A. Barnes' day, a "community" referred to a specific geographic location and studies of community ties had to do with who talked, associated, traded, and attended church with whom. Today, however, there are extended "online" communities developed through telecommunications devices and social network services. Such devices and services require extensive and ongoing maintenance and analysis, often using network science methods. Community development studies, today, also make extensive use of such methods.
[edit]Complex Networks
Complex networks require methods specific to modelling and interpreting social complexity and complex adaptive systems, including techniques of dynamic network analysis.
[edit]Criminal networks
In criminology and urban sociology, much attention has been paid to the social networks among criminal actors. For example, Andrew Papachristos[citation needed] has studied gang murders as a series of exchanges between gangs. Murders can be seen to diffuse outwards from a single source, because weaker gangs cannot afford to kill members of stronger gangs in retaliation, but must commit other violent acts to maintain their reputation for strength.
[edit]Diffusion of innovations
Diffusion of ideas and innovations studies focus on the spread and use of ideas from one actor to another or one culture and another. This line of research seeks to explain why some become "early adopters" of ideas and innovations, and links social network structure with facilitating or impeding the spread of an innovation.
[edit]Demography
In demography, the study of social networks has led to new sampling methods for estimating and reaching populations that are hard to enumerate (for example, homeless people or intravenous drug users.) For example, respondent driven sampling is a network-based sampling technique that relies on respondents to a survey recommending further respondents.
[edit]Economic sociology
The field of sociology focuses almost entirely on networks of outcomes of social interactions. More narrowly, economic sociology considers behavioral interactions of individuals and groups through social capital and social "markets". Sociologists, such as Mark Granovetter, have developed core principles about the interactions of social structure, information, ability to punish or reward, and trust that frequently recur in their analyses of political, economic and other institutions. Granovetter examines how social structures and social networks can affect economic outcomes like hiring, price, productivity and innovation and describes sociologists’ contributions to analyzing the impact of social structure and networks on the economy.[47]
[edit]Health care
Analysis of social networks is increasingly incorporated into heath care analytics, not only in epidemological studies but also in models of patient communication and education, disease prevention, mental health diagnosis and treatment, and in the study of health care organizations and systems.[48]
[edit]Human ecology
Human ecology is an interdisciplinary and transdisciplinary study of the relationship between humans and their natural, social, and built environments. The scientific philosophy of human ecology has a diffuse history with connections to geography, sociology, psychology, anthropology, zoology, and natural ecology.[49][50]
[edit]Language/Linguistics
Studies of language and lingustics, particularly evolutionary linguistics, focus on the development of linguistic forms and transfer of changes, sounds or words, from one language system to another through networks of social interaction. Social networks are also important in language shift, as groups of people add and/or abandon languages to their repertoire.
[edit]Organizational Studies
Research studies of formal or informal organizational relationships, organizational communication, economics, economic sociology, and other resource transfers. Social networks have also been used to examine how organizations interact with each other, characterizing the many informal connections that link executives together, as well as associations and connections between individual employees at different organizations [51]. Intra-organizational networks have been found to affect organizational commitment [52], organizational identification [37], interpersonal citizenship behaviour.[53]
[edit]Social capital
Social capital is a sociological concept which refers to the value of social relations and the role of cooperation and confidence to achieve positive outcomes. The term refers to the value one can get from their social ties. For example, newly arrived immigrants can make use of their social ties to established migrants to acquire jobs they may otherwise have trouble getting (e.g., because of lack of knowledge of language). Studies show that there a positive relationship between social capital and the intensity of social network use.[54]
Social network
Social network
This article is about the theoretical concept as used in the social and behavioral sciences. For social networking sites, see social networking service. For the 2010 movie, see The Social Network. For other uses, see Social network (disambiguation).
Sociology
Outline
Theory · History
Positivism · Antipositivism
Functionalism · Conflict theory
Middle-range · Mathematical
Critical theory · Socialization
Structure and agency
Research methods
Quantitative · Qualitative
Historical · Computational
Ethnographic · Network analytic
Topics · Subfields
Cities · Class · Crime · Culture
Deviance · Demography · Education
Economy · Environment · Family
Gender · Health · Industry · Internet
Knowledge · Law · Medicine
Politics · Mobility · Race and ethnicity
Rationalization · Religion · Science
Secularization · Social networks
Social psychology · Stratification
Browse
Portal
Category tree · Lists
Journals · Sociologists
Article index
v t e
Network science
Theory · History
Graph · Complex network · Contagion
Small-world · Scale-free ·
Community structure · Percolation · Evolution · Controllability · Topology · Graph drawing · Social capital · Link analysis · Optimization
Reciprocity · Closure · Homophily
Transitivity · Preferential attachment
Balance · Network effect · Influence
Types of Networks
Information · Telecommunication
Social · Biological · Neural · Semantic
Random · Dependency · Flow
Graphs
Vertex · Edge · Component
Directed · Multigraph · Bipartite
Weighted · Hypergraph · Random
Cycle · Loop · Path
Neighborhood · Clique · Complete · Cut
Data structure · Adjacency list & matrix
Incidence list & matrix
Metrics and Algorithms
Centrality · Degree · Betweenness
Closeness · PageRank · Motif
Clustering · Degree distribution · Assortativity · Distance · Modularity
Models
Random · Erdős–Rényi
Barabási–Albert · Watts–Strogatz
ERGM · Epidemic · Hierarchical
Browse
Topics · Software · Network scientists
Graph theory · Network theory
v t e
A social network is a social structure made up of a set of actors (such as individuals or organizations) and the dyadic ties between these actors. The social network perspective provides a clear way of analyzing the structure of whole social entities.[1] The study of these structures uses social network analysis to identify local and global patterns, locate influential entities, and examine network dynamics.
Social networks and the analysis of them is an inherently interdisciplinary academic field which emerged from social psychology, sociology, statistics, and graph theory. Georg Simmel authored early structural theories in sociology emphasizing the dynamics of triads and "web of group affiliations."[2] Jacob Moreno is credited with developing the first sociograms in the 1930s to study interpersonal relationships. These approaches were mathematically formalized in the 1950s and theories and methods of social networks became pervasive in the social and behavioral sciences by the 1980s.[1][3] Social network analysis is now one of the major paradigms in contemporary sociology, and is also employed in a number of other social and formal sciences. Together with other complex networks, it forms part of the nascent field of network science.[4][5]
Contents [hide]
1 Overview
2 History
3 Levels of analysis
3.1 Micro level
3.2 Meso level
3.3 Macro level
4 Theoretical Links
4.1 Imported Theories
4.2 Indigenous Theories
5 Research clusters
5.1 Communications
5.2 Community
5.3 Complex Networks
5.4 Criminal networks
5.5 Diffusion of innovations
5.6 Demography
5.7 Economic sociology
5.8 Health care
5.9 Human ecology
5.10 Language/Linguistics
5.11 Organizational Studies
5.12 Social capital
6 See also
7 References
8 Further reading
9 External links
9.1 Organizations
9.2 Peer-reviewed journals
9.3 Textbooks and educational resources
9.4 Data sets
[edit]Overview
Evolution graph of a social network: Barabási model.
A social network is a theoretical construct useful in the social sciences to study relationships between individuals, groups, organizations, or even entire societies (social units, see differentiation). The term is used to describe a social structure determined by such interactions. The ties through which any given social unit connects represent the convergence of the various social contacts of that unit. This theoretical approach is, necessarily, relational. An axiom of the social network approach to understanding social interaction is that social phenomena should be primarily conceived and investigated through the properties of relations between and within units, instead of the properties of these units themselves. Thus, one common criticism of social network theory is that individual agency is often ignored,[6] although this may not be the case in practice (see agent-based modeling). Precisely because many different types of relations, singular or in combination, form these network configurations, network analytics are useful to a broad range of research enterprises. In social science, these fields of study include, but are not limited to anthropology, biology, communication studies, economics, geography, information science, organizational studies, social psychology, sociology, and sociolinguistics.
[edit]History
Some of the ideas of the social network approach are found in writings going back to the ancient Greeks[citation needed]. In the late 1800s, both Émile Durkheim and Ferdinand Tönnies foreshadow the idea of social networks in their theories and research of social groups. Tönnies argued that social groups can exist as personal and direct social ties that either link individuals who share values and belief (Gemeinschaft, German, commonly translated as "community") or impersonal, formal, and instrumental social links (Gesellschaft, German, commonly translated as "society").[7] Durkheim gave a non-individualistic explanation of social facts arguing that social phenomena arise when interacting individuals constitute a reality that can no longer be accounted for in terms of the properties of individual actors.[8] Georg Simmel, writing at the turn of the twentieth century, pointed to the nature of networks and the effect of network size on interaction and examined the likelihood of interaction in loosely-knit networks rather than groups.[9]
Major developments in the field can be seen in the 1930s by several groups in psychology, anthropology, and mathematics working independently.[6] .[10][11] In psychology, in the 1930s, Jacob L. Moreno began systematic recording and analysis of social interaction in small groups, especially classrooms and work groups (see sociometry). In anthropology, the foundation for social network theory is the theoretical and ethnographic work of Bronislaw Malinowski,[12] Alfred Radcliffe-Brown,[13][14] and Claude Lévi-Strauss.[15] A group of social anthropologists associated with Max Gluckman and the Manchester School, including John A. Barnes,[16] J. Clyde Mitchell and Elizabeth Bott Spillius,[17][18] often are credited with performing some of the first fieldwork from which network analyses were performed, investigating community networks in southern Africa, India and the United Kingdom.[6] Concomitantly, British anthropologist S.F. Nadel codified a theory of social structure that was influential in later network analysis.[19] In sociology, the early (1930s) work of Talcott Parsons set the stage for taking a relational approach to understanding social structure.[20][21] Later, drawing upon Parsons' theory, the work of sociologist Peter Blau provides a strong impetus for analyzing the relational ties of social units with his work on social exchange theory.[22][23][24] By the 1970s, a growing number of scholars worked to combine the different tracks and traditions. One group consisted of sociologist Harrison White and his students at the Harvard University Department of Social Relations. Also independently active in the Harvard Social Relations department at the time were Charles Tilly, who focused on networks in political and community sociology and social movements, and Stanley Milgram, who developed the "six degrees of separation" thesis.[25]Mark Granovetter[26] and Barry Wellman[27] are among the former students of White who elaborated and championed the analysis of social networks.[28][29][30][31]
[edit]Levels of analysis
Self-organization of a network, based on Nagler, Levina, & Timme, (2011)[32]
In general, social networks are self-organizing, emergent, and complex, such that a globally coherent pattern appears from the local interaction of the elements that make up the system.[33][34] These patterns become more apparent as network size increases. However, a global network analysis of, for example, all interpersonal relationships in the world is not feasible and is likely to contain so much information as to be uninformative. Practical limitations of computing power, ethics and participant recruitment and payment also limit the scope of a social network analysis.[35][36] The nuances of a local system may be lost in a large network analysis, hence the quality of information may be more important than its scale for understanding network properties. Thus, social networks are analyzed at the scale relevant to the researcher's theoretical question. Although levels of analysis are not necessarily mutually exclusive, there are three general levels into which networks may fall: micro-level, meso-level, and macro-level.
This section requires expansion with:
additional examples and references for each sub-level.
[edit]Micro level
At the micro-level, social network research typically begins with an individual, snowballing as social relationships are traced, or may begin with a small group of individuals in a particular social context.
Social network diagram, micro-level.
Dyadic level: A dyad is a social relationship between two individuals. Network research on dyads may concentrate on structure of the relationship (e.g. multiplexity, strength), social equality, and tendencies toward reciprocity/mutuality.
Triadic level: Add one individual to a dyad, and you have a triad. Research at this level may concentrate on factors such as balance and transitivity, as well as social equality and tendencies toward reciprocity/mutuality.[35]
Actor level: The smallest unit of analysis in a social network is an individual in their social setting, i.e., an "actor" or "ego". Egonetwork analysis focuses on network characteristics such as size, relationship strength, density,centrality, prestige and roles such as isolates, liaisons, and bridges.[37] Such analyses, are most commonly used in the fields of psychology or social pyschology, ethnographic kinship analysis or other genealogical studies of relationships between individuals.
Subset level: Subset levels of network research problems begin at the micro-level, but may crossover into the meso-level of analysis. Subset level research may focus on distance and reachability, cliques, cohesive subgroups, or other group action, group actions or behavior[citation needed].
[edit]Meso level
In general, meso-level theories begin with a population size that falls between the micro- and macro-levels. However, meso-level may also refer to analyses that are specifically designed to reveal connections between micro- and macro-levels. Meso-level networks are low density and may exhibit causal processes distinct from interpersonal micro-level networks.[38]
Social network diagram, meso-level
Organizations: Formal organizations are social groups that distribute tasks for a collective goal.[39] Network research on organizations may focus on either intra-organizational or inter-organizational ties in terms of formal or informal relationships. Intra-organizational networks themselves often contain multiple levels of analysis, especially in larger organizations with multiple branches, franchises or semi-autonomous departments. In these cases, research is often conducted at a workgroup level and organization level, focusing on the interplay between the two structures.[40]
Randomly-distributed networks: Exponential random graph models of social networks became state-of-the-art methods of social network analysis in the 1980s. This framework has the capacity to represent social-structural effects commonly observed in many human social networks, including general degree-based structural effects commonly observed in many human social networks as well as reciprocity and transitivity, and at the node-level, homophily and attribute-based activity and popularity effects, as derived from explicit hypotheses about dependencies among network ties. Parameters are given in terms of the prevalence of small subgraph configurations in the network and can be interpreted as describing the combinations of local social processes from which a given network emerges. These probability models for networks on a given set of actors allow generalization beyond the restrictive dyadic independence assumption of micro-networks, allowing models to be built from theoretical structural foundations of social behavior.[41]
Examples of a random network and a scale-free network. Each graph has 32 nodes and 32 links. Note the "hubs" in the scale-free diagram (on the right).
Scale-free networks: A scale-free network is a network whose degree distribution follows a power law, at least asymptotically. In network theory a scale-free ideal network is a random network with a degree distribution that unravels the size distribution of social groups.[42] Specific characteristics of scale-free networks vary with the theories and analytical tools used to create them, however, in general, scale-free networks have some common characteristics. One notable characteristic in a scale-free network is the relative commonness of vertices with a degree that greatly exceeds the average. The highest-degree nodes are often called "hubs", and may serve specific purposes in their networks, although this depends greatly on the social context. Another general characteristic of scale-free networks is the clustering coefficient distribution, which decreases as the node degree increases. This distribution also follows a power law.[43] The Barabási model of network evolution shown above is an example of a scale-free network.
[edit]Macro level
Rather than tracing interpersonal interactions, macro-level analyses generally trace the outcomes of interactions, such as economic or other resource transfer interactions over a large population.
Diagram: section of a large-scale social network
Large-scale networks: Large-scale network is a term somewhat synonymous with "macro-level" as used, primarily, in social and behavioral sciences, in economics. Originally, the term was used extensively in the computer sciences (see large-scale network mapping).
Complex networks: Most larger social networks display features of social complexity, which involves substantial non-trivial features of network topology, with patterns of complex connections between elements that are neither purely regular nor purely random (see, complexity science, dynamical system and chaos theory), as do biological, and technological networks. Such complex network features include a heavy tail in the degree distribution, a high clustering coefficient, assortativity or disassortativity among vertices, community structure, and hierarchical structure. In the case of agency-directed networks these features also include reciprocity, triad significance profile (TSP, see network motif), and other features. In contrast, many of the mathematical models of networks that have been studied in the past, such as lattices and random graphs, do not show these features.[44]
[edit]Theoretical Links
[edit]Imported Theories
Various theoretical frameworks have be imported for the use of social network analysis. The most prominent of these are Graph Theory, Balance Theory, Social Comparison Theory, and more recently, the Social identity approach.[45]
[edit]Indigenous Theories
Few complete theories have been produced from social network analysis. Two that have areStructural Role Theory and Heterophily Theory.
The basis of Heterophily Theory was the finding in one study that more numerous weak ties can be important in seeking information and innovation, as cliques have a tendency to have more homogeneous opinions as well as share many common traits. This homophilic tendency was the reason for the members of the cliques to be attracted together in the first place. However, being similar, each member of the clique would also know more or less what the other members knew. To find new information or insights, members of the clique will have to look beyond the clique to its other friends and acquaintances. This is what Granovetter called "the strength of weak ties".[46]
This article is about the theoretical concept as used in the social and behavioral sciences. For social networking sites, see social networking service. For the 2010 movie, see The Social Network. For other uses, see Social network (disambiguation).
Sociology
Outline
Theory · History
Positivism · Antipositivism
Functionalism · Conflict theory
Middle-range · Mathematical
Critical theory · Socialization
Structure and agency
Research methods
Quantitative · Qualitative
Historical · Computational
Ethnographic · Network analytic
Topics · Subfields
Cities · Class · Crime · Culture
Deviance · Demography · Education
Economy · Environment · Family
Gender · Health · Industry · Internet
Knowledge · Law · Medicine
Politics · Mobility · Race and ethnicity
Rationalization · Religion · Science
Secularization · Social networks
Social psychology · Stratification
Browse
Portal
Category tree · Lists
Journals · Sociologists
Article index
v t e
Network science
Theory · History
Graph · Complex network · Contagion
Small-world · Scale-free ·
Community structure · Percolation · Evolution · Controllability · Topology · Graph drawing · Social capital · Link analysis · Optimization
Reciprocity · Closure · Homophily
Transitivity · Preferential attachment
Balance · Network effect · Influence
Types of Networks
Information · Telecommunication
Social · Biological · Neural · Semantic
Random · Dependency · Flow
Graphs
Vertex · Edge · Component
Directed · Multigraph · Bipartite
Weighted · Hypergraph · Random
Cycle · Loop · Path
Neighborhood · Clique · Complete · Cut
Data structure · Adjacency list & matrix
Incidence list & matrix
Metrics and Algorithms
Centrality · Degree · Betweenness
Closeness · PageRank · Motif
Clustering · Degree distribution · Assortativity · Distance · Modularity
Models
Random · Erdős–Rényi
Barabási–Albert · Watts–Strogatz
ERGM · Epidemic · Hierarchical
Browse
Topics · Software · Network scientists
Graph theory · Network theory
v t e
A social network is a social structure made up of a set of actors (such as individuals or organizations) and the dyadic ties between these actors. The social network perspective provides a clear way of analyzing the structure of whole social entities.[1] The study of these structures uses social network analysis to identify local and global patterns, locate influential entities, and examine network dynamics.
Social networks and the analysis of them is an inherently interdisciplinary academic field which emerged from social psychology, sociology, statistics, and graph theory. Georg Simmel authored early structural theories in sociology emphasizing the dynamics of triads and "web of group affiliations."[2] Jacob Moreno is credited with developing the first sociograms in the 1930s to study interpersonal relationships. These approaches were mathematically formalized in the 1950s and theories and methods of social networks became pervasive in the social and behavioral sciences by the 1980s.[1][3] Social network analysis is now one of the major paradigms in contemporary sociology, and is also employed in a number of other social and formal sciences. Together with other complex networks, it forms part of the nascent field of network science.[4][5]
Contents [hide]
1 Overview
2 History
3 Levels of analysis
3.1 Micro level
3.2 Meso level
3.3 Macro level
4 Theoretical Links
4.1 Imported Theories
4.2 Indigenous Theories
5 Research clusters
5.1 Communications
5.2 Community
5.3 Complex Networks
5.4 Criminal networks
5.5 Diffusion of innovations
5.6 Demography
5.7 Economic sociology
5.8 Health care
5.9 Human ecology
5.10 Language/Linguistics
5.11 Organizational Studies
5.12 Social capital
6 See also
7 References
8 Further reading
9 External links
9.1 Organizations
9.2 Peer-reviewed journals
9.3 Textbooks and educational resources
9.4 Data sets
[edit]Overview
Evolution graph of a social network: Barabási model.
A social network is a theoretical construct useful in the social sciences to study relationships between individuals, groups, organizations, or even entire societies (social units, see differentiation). The term is used to describe a social structure determined by such interactions. The ties through which any given social unit connects represent the convergence of the various social contacts of that unit. This theoretical approach is, necessarily, relational. An axiom of the social network approach to understanding social interaction is that social phenomena should be primarily conceived and investigated through the properties of relations between and within units, instead of the properties of these units themselves. Thus, one common criticism of social network theory is that individual agency is often ignored,[6] although this may not be the case in practice (see agent-based modeling). Precisely because many different types of relations, singular or in combination, form these network configurations, network analytics are useful to a broad range of research enterprises. In social science, these fields of study include, but are not limited to anthropology, biology, communication studies, economics, geography, information science, organizational studies, social psychology, sociology, and sociolinguistics.
[edit]History
Some of the ideas of the social network approach are found in writings going back to the ancient Greeks[citation needed]. In the late 1800s, both Émile Durkheim and Ferdinand Tönnies foreshadow the idea of social networks in their theories and research of social groups. Tönnies argued that social groups can exist as personal and direct social ties that either link individuals who share values and belief (Gemeinschaft, German, commonly translated as "community") or impersonal, formal, and instrumental social links (Gesellschaft, German, commonly translated as "society").[7] Durkheim gave a non-individualistic explanation of social facts arguing that social phenomena arise when interacting individuals constitute a reality that can no longer be accounted for in terms of the properties of individual actors.[8] Georg Simmel, writing at the turn of the twentieth century, pointed to the nature of networks and the effect of network size on interaction and examined the likelihood of interaction in loosely-knit networks rather than groups.[9]
Major developments in the field can be seen in the 1930s by several groups in psychology, anthropology, and mathematics working independently.[6] .[10][11] In psychology, in the 1930s, Jacob L. Moreno began systematic recording and analysis of social interaction in small groups, especially classrooms and work groups (see sociometry). In anthropology, the foundation for social network theory is the theoretical and ethnographic work of Bronislaw Malinowski,[12] Alfred Radcliffe-Brown,[13][14] and Claude Lévi-Strauss.[15] A group of social anthropologists associated with Max Gluckman and the Manchester School, including John A. Barnes,[16] J. Clyde Mitchell and Elizabeth Bott Spillius,[17][18] often are credited with performing some of the first fieldwork from which network analyses were performed, investigating community networks in southern Africa, India and the United Kingdom.[6] Concomitantly, British anthropologist S.F. Nadel codified a theory of social structure that was influential in later network analysis.[19] In sociology, the early (1930s) work of Talcott Parsons set the stage for taking a relational approach to understanding social structure.[20][21] Later, drawing upon Parsons' theory, the work of sociologist Peter Blau provides a strong impetus for analyzing the relational ties of social units with his work on social exchange theory.[22][23][24] By the 1970s, a growing number of scholars worked to combine the different tracks and traditions. One group consisted of sociologist Harrison White and his students at the Harvard University Department of Social Relations. Also independently active in the Harvard Social Relations department at the time were Charles Tilly, who focused on networks in political and community sociology and social movements, and Stanley Milgram, who developed the "six degrees of separation" thesis.[25]Mark Granovetter[26] and Barry Wellman[27] are among the former students of White who elaborated and championed the analysis of social networks.[28][29][30][31]
[edit]Levels of analysis
Self-organization of a network, based on Nagler, Levina, & Timme, (2011)[32]
In general, social networks are self-organizing, emergent, and complex, such that a globally coherent pattern appears from the local interaction of the elements that make up the system.[33][34] These patterns become more apparent as network size increases. However, a global network analysis of, for example, all interpersonal relationships in the world is not feasible and is likely to contain so much information as to be uninformative. Practical limitations of computing power, ethics and participant recruitment and payment also limit the scope of a social network analysis.[35][36] The nuances of a local system may be lost in a large network analysis, hence the quality of information may be more important than its scale for understanding network properties. Thus, social networks are analyzed at the scale relevant to the researcher's theoretical question. Although levels of analysis are not necessarily mutually exclusive, there are three general levels into which networks may fall: micro-level, meso-level, and macro-level.
This section requires expansion with:
additional examples and references for each sub-level.
[edit]Micro level
At the micro-level, social network research typically begins with an individual, snowballing as social relationships are traced, or may begin with a small group of individuals in a particular social context.
Social network diagram, micro-level.
Dyadic level: A dyad is a social relationship between two individuals. Network research on dyads may concentrate on structure of the relationship (e.g. multiplexity, strength), social equality, and tendencies toward reciprocity/mutuality.
Triadic level: Add one individual to a dyad, and you have a triad. Research at this level may concentrate on factors such as balance and transitivity, as well as social equality and tendencies toward reciprocity/mutuality.[35]
Actor level: The smallest unit of analysis in a social network is an individual in their social setting, i.e., an "actor" or "ego". Egonetwork analysis focuses on network characteristics such as size, relationship strength, density,centrality, prestige and roles such as isolates, liaisons, and bridges.[37] Such analyses, are most commonly used in the fields of psychology or social pyschology, ethnographic kinship analysis or other genealogical studies of relationships between individuals.
Subset level: Subset levels of network research problems begin at the micro-level, but may crossover into the meso-level of analysis. Subset level research may focus on distance and reachability, cliques, cohesive subgroups, or other group action, group actions or behavior[citation needed].
[edit]Meso level
In general, meso-level theories begin with a population size that falls between the micro- and macro-levels. However, meso-level may also refer to analyses that are specifically designed to reveal connections between micro- and macro-levels. Meso-level networks are low density and may exhibit causal processes distinct from interpersonal micro-level networks.[38]
Social network diagram, meso-level
Organizations: Formal organizations are social groups that distribute tasks for a collective goal.[39] Network research on organizations may focus on either intra-organizational or inter-organizational ties in terms of formal or informal relationships. Intra-organizational networks themselves often contain multiple levels of analysis, especially in larger organizations with multiple branches, franchises or semi-autonomous departments. In these cases, research is often conducted at a workgroup level and organization level, focusing on the interplay between the two structures.[40]
Randomly-distributed networks: Exponential random graph models of social networks became state-of-the-art methods of social network analysis in the 1980s. This framework has the capacity to represent social-structural effects commonly observed in many human social networks, including general degree-based structural effects commonly observed in many human social networks as well as reciprocity and transitivity, and at the node-level, homophily and attribute-based activity and popularity effects, as derived from explicit hypotheses about dependencies among network ties. Parameters are given in terms of the prevalence of small subgraph configurations in the network and can be interpreted as describing the combinations of local social processes from which a given network emerges. These probability models for networks on a given set of actors allow generalization beyond the restrictive dyadic independence assumption of micro-networks, allowing models to be built from theoretical structural foundations of social behavior.[41]
Examples of a random network and a scale-free network. Each graph has 32 nodes and 32 links. Note the "hubs" in the scale-free diagram (on the right).
Scale-free networks: A scale-free network is a network whose degree distribution follows a power law, at least asymptotically. In network theory a scale-free ideal network is a random network with a degree distribution that unravels the size distribution of social groups.[42] Specific characteristics of scale-free networks vary with the theories and analytical tools used to create them, however, in general, scale-free networks have some common characteristics. One notable characteristic in a scale-free network is the relative commonness of vertices with a degree that greatly exceeds the average. The highest-degree nodes are often called "hubs", and may serve specific purposes in their networks, although this depends greatly on the social context. Another general characteristic of scale-free networks is the clustering coefficient distribution, which decreases as the node degree increases. This distribution also follows a power law.[43] The Barabási model of network evolution shown above is an example of a scale-free network.
[edit]Macro level
Rather than tracing interpersonal interactions, macro-level analyses generally trace the outcomes of interactions, such as economic or other resource transfer interactions over a large population.
Diagram: section of a large-scale social network
Large-scale networks: Large-scale network is a term somewhat synonymous with "macro-level" as used, primarily, in social and behavioral sciences, in economics. Originally, the term was used extensively in the computer sciences (see large-scale network mapping).
Complex networks: Most larger social networks display features of social complexity, which involves substantial non-trivial features of network topology, with patterns of complex connections between elements that are neither purely regular nor purely random (see, complexity science, dynamical system and chaos theory), as do biological, and technological networks. Such complex network features include a heavy tail in the degree distribution, a high clustering coefficient, assortativity or disassortativity among vertices, community structure, and hierarchical structure. In the case of agency-directed networks these features also include reciprocity, triad significance profile (TSP, see network motif), and other features. In contrast, many of the mathematical models of networks that have been studied in the past, such as lattices and random graphs, do not show these features.[44]
[edit]Theoretical Links
[edit]Imported Theories
Various theoretical frameworks have be imported for the use of social network analysis. The most prominent of these are Graph Theory, Balance Theory, Social Comparison Theory, and more recently, the Social identity approach.[45]
[edit]Indigenous Theories
Few complete theories have been produced from social network analysis. Two that have areStructural Role Theory and Heterophily Theory.
The basis of Heterophily Theory was the finding in one study that more numerous weak ties can be important in seeking information and innovation, as cliques have a tendency to have more homogeneous opinions as well as share many common traits. This homophilic tendency was the reason for the members of the cliques to be attracted together in the first place. However, being similar, each member of the clique would also know more or less what the other members knew. To find new information or insights, members of the clique will have to look beyond the clique to its other friends and acquaintances. This is what Granovetter called "the strength of weak ties".[46]
Online business networking
Online business networking
Businesses are increasingly using business social networks as a means of growing their circle of business contacts and promoting themselves online. In general these networking tools allow professionals to build up their circle of business partners they trust. By connecting these business partners the networking tools allow individuals to search for certain people within their network. Through introductions, the members of these tools then can get in contact with new prospective business partners. Since businesses are expanding globally, social networks make it easier to keep in touch with other contacts around the world. Specific cross-border e-commerce platforms and business partnering networks now make globalization accessible also for small and medium sized companies. Few example for online business networking platforms are Yceeya, Linkedin, etc.
[edit]Face-to-face business networking
Professionals who wish to leverage their presentation skills with the urgency of physically being present attend general and exclusive events. Many professionals tend to prefer face-to-face networking over online based networking because the potential for higher quality relationships are possible. Many individuals also prefer face-to-face because people tend to prefer actually knowing and meeting who they intend to do business with.
Face to face business networking is often facilitated by referral networking clubs.
There are many Face to Face business networking platforms such as Yceeya and meetup.
[edit]General business networking
Before online networking, there was and has always been, networking face-to-face. "Schmoozing" or "rubbing elbows" are expressions used among business professionals for introducing and meeting one another, and establishing rapport.
[edit]Networked Businesses
With networking developing, many businesses now have this as a core part of their strategy. Those that have developed a strong network of connections suppliers and companies can be seen as Networked Businesses, and will tend to source the business and their suppliers through the network of relationships that they have in place. Networked businesses tend to be open, random, and supportive, whereas those relying on hierarchical, traditional managed approaches are closed, selective, and controlling. These phrases were first used by Thomas Power, chairman of Ecademy, an online business network, in May 2009.
[edit]Business networking in the ICT domain
Companies and organizations, and related value chains and value networks need some sort of IT support. Traditionally, it is provided by software applications, software packages, ERPs, and/or workflows; presently, also by different types of web-based innovations.
A truly ICT business networking approach rethinks and rebuilds the operating support from scratch, around two key business features: information contributions, to be provided by the activities involved, whether they are performed by human beings, automated tools or jointly by the two, in a coordinated way; and automated information exchanges, to be provided by the TLC network.
Information contributions and exchanges, in turn, need to be supported by data storage and access security (signature, encryption, authentication, decryption), which both can be provided either as add-ons or as built-in features.
Yceeya is an good example for the mixture of Face to face and online networking.
[edit]See also
Professional network service
Personal Network
[edit]References
9 Ways To Leverage Your Online Business Networking Activities, April 18, 2010
Hubert Österle, Elgar Fleisch, Rainer Alt (2001), Business networking: shaping collaboration between enterprises (2, illustrated ed.), Springer, ISBN 3-540-41351-0, 9783540413516
About Yceeya network,June 13,2012Online business networking
Businesses are increasingly using business social networks as a means of growing their circle of business contacts and promoting themselves online. In general these networking tools allow professionals to build up their circle of business partners they trust. By connecting these business partners the networking tools allow individuals to search for certain people within their network. Through introductions, the members of these tools then can get in contact with new prospective business partners. Since businesses are expanding globally, social networks make it easier to keep in touch with other contacts around the world. Specific cross-border e-commerce platforms and business partnering networks now make globalization accessible also for small and medium sized companies. Few example for online business networking platforms are Yceeya, Linkedin, etc.
[edit]Face-to-face business networking
Professionals who wish to leverage their presentation skills with the urgency of physically being present attend general and exclusive events. Many professionals tend to prefer face-to-face networking over online based networking because the potential for higher quality relationships are possible. Many individuals also prefer face-to-face because people tend to prefer actually knowing and meeting who they intend to do business with.
Face to face business networking is often facilitated by referral networking clubs.
There are many Face to Face business networking platforms such as Yceeya and meetup.
[edit]General business networking
Before online networking, there was and has always been, networking face-to-face. "Schmoozing" or "rubbing elbows" are expressions used among business professionals for introducing and meeting one another, and establishing rapport.
[edit]Networked Businesses
With networking developing, many businesses now have this as a core part of their strategy. Those that have developed a strong network of connections suppliers and companies can be seen as Networked Businesses, and will tend to source the business and their suppliers through the network of relationships that they have in place. Networked businesses tend to be open, random, and supportive, whereas those relying on hierarchical, traditional managed approaches are closed, selective, and controlling. These phrases were first used by Thomas Power, chairman of Ecademy, an online business network, in May 2009.
[edit]Business networking in the ICT domain
Companies and organizations, and related value chains and value networks need some sort of IT support. Traditionally, it is provided by software applications, software packages, ERPs, and/or workflows; presently, also by different types of web-based innovations.
A truly ICT business networking approach rethinks and rebuilds the operating support from scratch, around two key business features: information contributions, to be provided by the activities involved, whether they are performed by human beings, automated tools or jointly by the two, in a coordinated way; and automated information exchanges, to be provided by the TLC network.
Information contributions and exchanges, in turn, need to be supported by data storage and access security (signature, encryption, authentication, decryption), which both can be provided either as add-ons or as built-in features.
Yceeya is an good example for the mixture of Face to face and online networking.
[edit]See also
Professional network service
Personal Network
[edit]References
9 Ways To Leverage Your Online Business Networking Activities, April 18, 2010
Hubert Österle, Elgar Fleisch, Rainer Alt (2001), Business networking: shaping collaboration between enterprises (2, illustrated ed.), Springer, ISBN 3-540-41351-0, 9783540413516
About Yceeya network,June 13,2012Online business networking
Large firms networks vs. small business networks
Large firms networks vs. small business networks
Large firms networks spread wider than small business, but the difference between the two types is that to be part of a large firm network you have to achieve a preset level of success, for example fly over to China find out which factory manufactures your favorite product, go to the factory owner, offer to buy a large quantity of the product, he will give you a quote; when he does take that quote and compare to current retail prices, if it's not lower than the retail market by 300 percent to 400 percent, then this factory is part of a business network, meaning they provide the special price only to the network members. This keeps the real value of the product hidden from the public and only available to the large firms they deal with.
Large firms networks spread wider than small business, but the difference between the two types is that to be part of a large firm network you have to achieve a preset level of success, for example fly over to China find out which factory manufactures your favorite product, go to the factory owner, offer to buy a large quantity of the product, he will give you a quote; when he does take that quote and compare to current retail prices, if it's not lower than the retail market by 300 percent to 400 percent, then this factory is part of a business network, meaning they provide the special price only to the network members. This keeps the real value of the product hidden from the public and only available to the large firms they deal with.
Business networking
Business networking
Business networking is a socioeconomic activity by which groups of like-minded businesspeople recognize, create, or act upon business opportunities. A business network is a type of social network whose reason for existing is business activity. There are several prominent business networking organizations that create models of networking activity that, when followed, allow the business person to build new business relationships and generate business opportunities at the same time. A professional network service is an implementation of information technology in support of business networking. Many businesspeople contend business networking is a more cost-effective method of generating new business than advertising or public relations efforts. This is because business networking is a low-cost activity that involves more personal commitment than company money.
As an example, a business network may agree to meet weekly or monthly with the purpose of exchanging business leads and referrals with fellow members. To complement this activity, members often meet outside this circle, on their own time, and build their own one-to-one relationship with the fellow member.
Business networking can be conducted in a local business community, or on a larger scale via the Internet. Business networking websites have grown over recent years due to the Internet's ability to connect people from all over the world. Internet companies often set up business leads for sale to bigger corporations and companies looking for data sources.
Business networking can have a meaning also in the ICT domain, i.e. the provision of operating support to companies and organizations, and related value chains and value networks.
It refers to an activity coordination with a wider scope and a simpler implementation than pre-organized workflows or web-based impromptu searches for transaction counterparts (workflow is useful to coordinate activities, but it is complicated by the use of s.c. patterns to deviate the flow of work from a pure sequence, in order to compensate its intrinsic linearity; impromptu searches for transaction counterparts on the web are useful as well, but only for non-strategic supplies; both are complicated by a plethora of interfaces needed among different organizations and even between different IT applications within the same organization).
Business networking is a socioeconomic activity by which groups of like-minded businesspeople recognize, create, or act upon business opportunities. A business network is a type of social network whose reason for existing is business activity. There are several prominent business networking organizations that create models of networking activity that, when followed, allow the business person to build new business relationships and generate business opportunities at the same time. A professional network service is an implementation of information technology in support of business networking. Many businesspeople contend business networking is a more cost-effective method of generating new business than advertising or public relations efforts. This is because business networking is a low-cost activity that involves more personal commitment than company money.
As an example, a business network may agree to meet weekly or monthly with the purpose of exchanging business leads and referrals with fellow members. To complement this activity, members often meet outside this circle, on their own time, and build their own one-to-one relationship with the fellow member.
Business networking can be conducted in a local business community, or on a larger scale via the Internet. Business networking websites have grown over recent years due to the Internet's ability to connect people from all over the world. Internet companies often set up business leads for sale to bigger corporations and companies looking for data sources.
Business networking can have a meaning also in the ICT domain, i.e. the provision of operating support to companies and organizations, and related value chains and value networks.
It refers to an activity coordination with a wider scope and a simpler implementation than pre-organized workflows or web-based impromptu searches for transaction counterparts (workflow is useful to coordinate activities, but it is complicated by the use of s.c. patterns to deviate the flow of work from a pure sequence, in order to compensate its intrinsic linearity; impromptu searches for transaction counterparts on the web are useful as well, but only for non-strategic supplies; both are complicated by a plethora of interfaces needed among different organizations and even between different IT applications within the same organization).
Communication media
Communication media
Computer networks can be classified according to the hardware and associated software technology that is used to interconnect the individual devices in the network, such as electrical cable (HomePNA, power line communication, G.hn), optical fiber, and radio waves (wireless LAN). In the OSI model, these are located at levels 1 and 2.
A well-known family of communication media is collectively known as Ethernet. It is defined by IEEE 802 and utilizes various standards and media that enable communication between devices. Wireless LAN technology is designed to connect devices without wiring. These devices use radio waves or infrared signals as a transmission medium.
[edit]Wired technologies
The order of the following wired technologies is, roughly, from slowest to fastest transmission speed.
Twisted pair wire is the most widely used medium for telecommunication. Twisted-pair cabling consist of copper wires that are twisted into pairs. Ordinary telephone wires consist of two insulated copper wires twisted into pairs. Computer networking cabling (wired Ethernet as defined by IEEE 802.3) consists of 4 pairs of copper cabling that can be utilized for both voice and data transmission. The use of two wires twisted together helps to reduce crosstalk and electromagnetic induction. The transmission speed ranges from 2 million bits per second to 10 billion bits per second. Twisted pair cabling comes in two forms: unshielded twisted pair (UTP) and shielded twisted-pair (STP). Each form comes in several category ratings, designed for use in various scenarios.
Coaxial cable is widely used for cable television systems, office buildings, and other work-sites for local area networks. The cables consist of copper or aluminum wire surrounded by an insulating layer (typically a flexible material with a high dielectric constant), which itself is surrounded by a conductive layer. The insulation helps minimize interference and distortion. Transmission speed ranges from 200 million bits per second to more than 500 million bits per second.
ITU-T G.hn technology uses existing home wiring (coaxial cable, phone lines and power lines) to create a high-speed (up to 1 Gigabit/s) local area network.
An optical fiber is a glass fiber. It uses pulses of light to transmit data. Some advantages of optical fibers over metal wires are less transmission loss, immunity from electromagnetic radiation, and very fast transmission speed, up to trillions of bits per second. One can use different colors of lights to increase the number of messages being sent over a fiber optic cable.
[edit]Wireless technologies
Terrestrial microwave – Terrestrial microwave communication uses Earth-based transmitters and receivers resembling satellite dishes. Terrestrial microwaves are in the low-gigahertz range, which limits all communications to line-of-sight. Relay stations are spaced approximately 48 km (30 mi) apart.
Communications satellites – The satellites communicate via microwave radio waves, which are not deflected by the Earth's atmosphere. The satellites are stationed in space, typically in geosynchronous orbit 35,400 km (22,000 mi) above the equator. These Earth-orbiting systems are capable of receiving and relaying voice, data, and TV signals.
Cellular and PCS systems use several radio communications technologies. The systems divide the region covered into multiple geographic areas. Each area has a low-power transmitter or radio relay antenna device to relay calls from one area to the next area.
Radio and spread spectrum technologies – Wireless local area network use a high-frequency radio technology similar to digital cellular and a low-frequency radio technology. Wireless LANs use spread spectrum technology to enable communication between multiple devices in a limited area. IEEE 802.11 defines a common flavor of open-standards wireless radio-wave technology.
Infrared communication can transmit signals for small distances, typically no more than 10 meters. In most cases, line-of-sight propagation is used, which limits the physical positioning of communicating devices.
A global area network (GAN) is a network used for supporting mobile across an arbitrary number of wireless LANs, satellite coverage areas, etc. The key challenge in mobile communications is handing off user communications from one local coverage area to the next. In IEEE Project 802, this involves a succession of terrestrial wireless LANs.[7]
[edit]Exotic technologies
There have been various attempts at transporting data over more or less exotic media:
IP over Avian Carriers was a humorous April fool's Request for Comments, issued as RFC 1149. It was implemented in real life in 2001.[8]
Extending the Internet to interplanetary dimensions via radio waves.[9]
Both cases have a large round-trip delay time, which prevents useful communication.
[edit]Communications protocols and network programming
Internet map. The Internet is a global system of interconnected computer networks that use the standard Internet Protocol Suite (TCP/IP) to serve billions of users worldwide.
Main article: Communications protocol
A communications protocol is a set of rules for exchanging information over a network. It is typically a protocol stack (also see the OSI model), which is a "stack" of protocols, in which each protocol uses the protocol below it. An important example of a protocol stack is HTTP running over TCP over IP over IEEE 802.11 (TCP and IP are members of the Internet Protocol Suite, and IEEE 802.11 is a member of the Ethernet protocol suite). This stack is used between the wireless router and the home user's personal computer when the user is surfing the web.
Communication protocols have various properties, such as whether they are connection-oriented or connectionless, whether they use circuit mode or packet switching, or whether they use hierarchical or flat addressing.
There are many communication protocols, a few of which are described below.
[edit]Ethernet
Main article: Ethernet
Ethernet is a family of connectionless protocols used in LANs, described by a set of standards together called IEEE 802 published by the Institute of Electrical and Electronics Engineers. It has a flat addressing scheme and is mostly situated at levels 1 and 2 of the OSI model. For home users today, the most well-known member of this protocol family is IEEE 802.11, otherwise known as Wireless LAN (WLAN). However, the complete protocol suite deals with a multitude of networking aspects not only for home use, but especially when the technology is deployed to support a diverse range of business needs. MAC bridging (IEEE 802.1D) deals with the routing of Ethernet packets using a Spanning Tree Protocol, IEEE 802.1Q describes VLANs, and IEEE 802.1X defines a port-based Network Access Control protocol, which forms the basis for the authentication mechanisms used in VLANs, but it is also found in WLANs – it is what the home user sees when the user has to enter a "wireless access key".
[edit]Internet Protocol Suite
The Internet Protocol Suite, often also called TCP/IP, is the foundation of all modern internetworking. It offers connection-less as well as connection-oriented services over an inherently unreliable network traversed by datagram transmission at the Internet protocol (IP) level. At its core, the protocol suite defines the addressing, identification, and routing specification in form of the traditional Internet Protocol Version 4 (IPv4) and IPv6, the next generation of the protocol with a much enlarged addressing capability.
[edit]SONET/SDH
Main article: Synchronous optical networking
Synchronous Optical Networking (SONET) and Synchronous Digital Hierarchy (SDH) are standardized multiplexing protocols that transfer multiple digital bit streams over optical fiber using lasers. They were originally designed to transport circuit mode communications from a variety of different sources, primarily to support real-time, uncompressed, circuit-switched voice encoded in PCM(Pulse-Code Modulation) format. However, due to its protocol neutrality and transport-oriented features, SONET/SDH also was the obvious choice for transporting Asynchronous Transfer Mode (ATM) frames.
[edit]Asynchronous Transfer Mode
Main article: Asynchronous transfer mode
Asynchronous Transfer Mode (ATM) is a switching technique for telecommunication networks. It uses asynchronous time-division multiplexing and encodes data into small, fixed-sized cells. This differs from other protocols such as the Internet Protocol Suite or Ethernet that use variable sized packets or frames. ATM has similarity with both circuit and packet switched networking. This makes it a good choice for a network that must handle both traditional high-throughput data traffic, and real-time, low-latency content such as voice and video. ATM uses a connection-oriented model in which a virtual circuit must be established between two endpoints before the actual data exchange begins.
While the role of ATM is diminishing in favor of next-generation networks, it still plays a role in the last mile, which is the connection between an Internet service provider and the home user. For an interesting write-up of the technologies involved, including the deep stacking of communications protocols used, see.[10]
[edit]Network programming
Main article: Computer network programming
Main article: Network socket
Computer network programming involves writing computer programs that communicate with each other across a computer network. Different programs must be written for the client process, which initiates the communication, and for the server process, which waits for the communication to be initiated. Both endpoints of the communication flow are implemented as network sockets; hence network programming is basically socket programming.
[edit]Scale
Computer networks can be classified according to the hardware and associated software technology that is used to interconnect the individual devices in the network, such as electrical cable (HomePNA, power line communication, G.hn), optical fiber, and radio waves (wireless LAN). In the OSI model, these are located at levels 1 and 2.
A well-known family of communication media is collectively known as Ethernet. It is defined by IEEE 802 and utilizes various standards and media that enable communication between devices. Wireless LAN technology is designed to connect devices without wiring. These devices use radio waves or infrared signals as a transmission medium.
[edit]Wired technologies
The order of the following wired technologies is, roughly, from slowest to fastest transmission speed.
Twisted pair wire is the most widely used medium for telecommunication. Twisted-pair cabling consist of copper wires that are twisted into pairs. Ordinary telephone wires consist of two insulated copper wires twisted into pairs. Computer networking cabling (wired Ethernet as defined by IEEE 802.3) consists of 4 pairs of copper cabling that can be utilized for both voice and data transmission. The use of two wires twisted together helps to reduce crosstalk and electromagnetic induction. The transmission speed ranges from 2 million bits per second to 10 billion bits per second. Twisted pair cabling comes in two forms: unshielded twisted pair (UTP) and shielded twisted-pair (STP). Each form comes in several category ratings, designed for use in various scenarios.
Coaxial cable is widely used for cable television systems, office buildings, and other work-sites for local area networks. The cables consist of copper or aluminum wire surrounded by an insulating layer (typically a flexible material with a high dielectric constant), which itself is surrounded by a conductive layer. The insulation helps minimize interference and distortion. Transmission speed ranges from 200 million bits per second to more than 500 million bits per second.
ITU-T G.hn technology uses existing home wiring (coaxial cable, phone lines and power lines) to create a high-speed (up to 1 Gigabit/s) local area network.
An optical fiber is a glass fiber. It uses pulses of light to transmit data. Some advantages of optical fibers over metal wires are less transmission loss, immunity from electromagnetic radiation, and very fast transmission speed, up to trillions of bits per second. One can use different colors of lights to increase the number of messages being sent over a fiber optic cable.
[edit]Wireless technologies
Terrestrial microwave – Terrestrial microwave communication uses Earth-based transmitters and receivers resembling satellite dishes. Terrestrial microwaves are in the low-gigahertz range, which limits all communications to line-of-sight. Relay stations are spaced approximately 48 km (30 mi) apart.
Communications satellites – The satellites communicate via microwave radio waves, which are not deflected by the Earth's atmosphere. The satellites are stationed in space, typically in geosynchronous orbit 35,400 km (22,000 mi) above the equator. These Earth-orbiting systems are capable of receiving and relaying voice, data, and TV signals.
Cellular and PCS systems use several radio communications technologies. The systems divide the region covered into multiple geographic areas. Each area has a low-power transmitter or radio relay antenna device to relay calls from one area to the next area.
Radio and spread spectrum technologies – Wireless local area network use a high-frequency radio technology similar to digital cellular and a low-frequency radio technology. Wireless LANs use spread spectrum technology to enable communication between multiple devices in a limited area. IEEE 802.11 defines a common flavor of open-standards wireless radio-wave technology.
Infrared communication can transmit signals for small distances, typically no more than 10 meters. In most cases, line-of-sight propagation is used, which limits the physical positioning of communicating devices.
A global area network (GAN) is a network used for supporting mobile across an arbitrary number of wireless LANs, satellite coverage areas, etc. The key challenge in mobile communications is handing off user communications from one local coverage area to the next. In IEEE Project 802, this involves a succession of terrestrial wireless LANs.[7]
[edit]Exotic technologies
There have been various attempts at transporting data over more or less exotic media:
IP over Avian Carriers was a humorous April fool's Request for Comments, issued as RFC 1149. It was implemented in real life in 2001.[8]
Extending the Internet to interplanetary dimensions via radio waves.[9]
Both cases have a large round-trip delay time, which prevents useful communication.
[edit]Communications protocols and network programming
Internet map. The Internet is a global system of interconnected computer networks that use the standard Internet Protocol Suite (TCP/IP) to serve billions of users worldwide.
Main article: Communications protocol
A communications protocol is a set of rules for exchanging information over a network. It is typically a protocol stack (also see the OSI model), which is a "stack" of protocols, in which each protocol uses the protocol below it. An important example of a protocol stack is HTTP running over TCP over IP over IEEE 802.11 (TCP and IP are members of the Internet Protocol Suite, and IEEE 802.11 is a member of the Ethernet protocol suite). This stack is used between the wireless router and the home user's personal computer when the user is surfing the web.
Communication protocols have various properties, such as whether they are connection-oriented or connectionless, whether they use circuit mode or packet switching, or whether they use hierarchical or flat addressing.
There are many communication protocols, a few of which are described below.
[edit]Ethernet
Main article: Ethernet
Ethernet is a family of connectionless protocols used in LANs, described by a set of standards together called IEEE 802 published by the Institute of Electrical and Electronics Engineers. It has a flat addressing scheme and is mostly situated at levels 1 and 2 of the OSI model. For home users today, the most well-known member of this protocol family is IEEE 802.11, otherwise known as Wireless LAN (WLAN). However, the complete protocol suite deals with a multitude of networking aspects not only for home use, but especially when the technology is deployed to support a diverse range of business needs. MAC bridging (IEEE 802.1D) deals with the routing of Ethernet packets using a Spanning Tree Protocol, IEEE 802.1Q describes VLANs, and IEEE 802.1X defines a port-based Network Access Control protocol, which forms the basis for the authentication mechanisms used in VLANs, but it is also found in WLANs – it is what the home user sees when the user has to enter a "wireless access key".
[edit]Internet Protocol Suite
The Internet Protocol Suite, often also called TCP/IP, is the foundation of all modern internetworking. It offers connection-less as well as connection-oriented services over an inherently unreliable network traversed by datagram transmission at the Internet protocol (IP) level. At its core, the protocol suite defines the addressing, identification, and routing specification in form of the traditional Internet Protocol Version 4 (IPv4) and IPv6, the next generation of the protocol with a much enlarged addressing capability.
[edit]SONET/SDH
Main article: Synchronous optical networking
Synchronous Optical Networking (SONET) and Synchronous Digital Hierarchy (SDH) are standardized multiplexing protocols that transfer multiple digital bit streams over optical fiber using lasers. They were originally designed to transport circuit mode communications from a variety of different sources, primarily to support real-time, uncompressed, circuit-switched voice encoded in PCM(Pulse-Code Modulation) format. However, due to its protocol neutrality and transport-oriented features, SONET/SDH also was the obvious choice for transporting Asynchronous Transfer Mode (ATM) frames.
[edit]Asynchronous Transfer Mode
Main article: Asynchronous transfer mode
Asynchronous Transfer Mode (ATM) is a switching technique for telecommunication networks. It uses asynchronous time-division multiplexing and encodes data into small, fixed-sized cells. This differs from other protocols such as the Internet Protocol Suite or Ethernet that use variable sized packets or frames. ATM has similarity with both circuit and packet switched networking. This makes it a good choice for a network that must handle both traditional high-throughput data traffic, and real-time, low-latency content such as voice and video. ATM uses a connection-oriented model in which a virtual circuit must be established between two endpoints before the actual data exchange begins.
While the role of ATM is diminishing in favor of next-generation networks, it still plays a role in the last mile, which is the connection between an Internet service provider and the home user. For an interesting write-up of the technologies involved, including the deep stacking of communications protocols used, see.[10]
[edit]Network programming
Main article: Computer network programming
Main article: Network socket
Computer network programming involves writing computer programs that communicate with each other across a computer network. Different programs must be written for the client process, which initiates the communication, and for the server process, which waits for the communication to be initiated. Both endpoints of the communication flow are implemented as network sockets; hence network programming is basically socket programming.
[edit]Scale
Properties
Properties
Computer networks:
Facilitate communications
Using a network, people can communicate efficiently and easily via email, instant messaging, chat rooms, telephone, video telephone calls, and video conferencing.
Permit sharing of files, data, and other types of information
In a network environment, authorized users may access data and information stored on other computers on the network. The capability of providing access to data and information on shared storage devices is an important feature of many networks.
Share network and computing resources
In a networked environment, each computer on a network may access and use resources provided by devices on the network, such as printing a document on a shared network printer. Distributed computing uses computing resources across a network to accomplish tasks.
May be insecure
A computer network may be used by computer hackers to deploy computer viruses or computer worms on devices connected to the network, or to prevent these devices from normally accessing the network (denial of service).
May interfere with other technologies
Power line communication strongly disturbs certain forms of radio communication, e.g., amateur radio.[5] It may also interfere with last mile access technologies such as ADSL and VDSL.[6]
May be difficult to set up
A complex computer network may be difficult to set up. It may also be very costly to set up an effective computer network in a large organization or company.
Computer networks:
Facilitate communications
Using a network, people can communicate efficiently and easily via email, instant messaging, chat rooms, telephone, video telephone calls, and video conferencing.
Permit sharing of files, data, and other types of information
In a network environment, authorized users may access data and information stored on other computers on the network. The capability of providing access to data and information on shared storage devices is an important feature of many networks.
Share network and computing resources
In a networked environment, each computer on a network may access and use resources provided by devices on the network, such as printing a document on a shared network printer. Distributed computing uses computing resources across a network to accomplish tasks.
May be insecure
A computer network may be used by computer hackers to deploy computer viruses or computer worms on devices connected to the network, or to prevent these devices from normally accessing the network (denial of service).
May interfere with other technologies
Power line communication strongly disturbs certain forms of radio communication, e.g., amateur radio.[5] It may also interfere with last mile access technologies such as ADSL and VDSL.[6]
May be difficult to set up
A complex computer network may be difficult to set up. It may also be very costly to set up an effective computer network in a large organization or company.
History
History
Before the advent of computer networks that were based upon some type of telecommunications system, communication between calculation machines and early computers was performed by human users by carrying instructions between them. Many of the social behaviors seen in today's Internet were demonstrably present in the 19th century and arguably in even earlier networks using visual signals.
In September 1940, George Stibitz used a Teletype machine to send instructions for a problem set from his Model at Dartmouth College to his Complex Number Calculator in New York and received results back by the same means. Linking output systems like teletypewriters to computers was an interest at the Advanced Research Projects Agency (ARPA) when, in 1962, J.C.R. Licklider was hired and developed a working group he called the "Intergalactic Computer Network", a precursor to the ARPANET.
Early networks of communicating computers included the military radar system Semi-Automatic Ground Environment (SAGE), started in the late 1950s.
The commercial airline reservation system semi-automatic business research environment (SABRE) went online with two connected mainframes in 1960.[2][3]
In 1964, researchers at Dartmouth developed the Dartmouth Time Sharing System for distributed users of large computer systems. The same year, at Massachusetts Institute of Technology, a research group supported by General Electric and Bell Labs used a computer to route and manage telephone connections.
Throughout the 1960s Leonard Kleinrock, Paul Baran and Donald Davies independently conceptualized and developed network systems which used packets that could be used in a network between computer systems.
1965 Thomas Merrill and Lawrence G. Roberts created the first wide area network (WAN).
The first widely used telephone switch that used true computer control was introduced by Western Electric in 1965.
In 1969 the University of California at Los Angeles, the Stanford Research Institute, University of California at Santa Barbara, and the University of Utah were connected as the beginning of the ARPANET network using 50 kbit/s circuits.[4]
Commercial services using X.25 were deployed in 1972, and later used as an underlying infrastructure for expanding TCP/IP networks.
Today, computer networks are the core of modern communication. All modern aspects of the public switched telephone network (PSTN) are computer-controlled, and telephony increasingly runs over the Internet Protocol, although not necessarily the public Internet. The scope of communication has increased significantly in the past decade, and this boom in communications would not have been possible without the progressively advancing computer network. Computer networks, and the technologies needed to connect and communicate through and between them, continue to drive computer hardware, software, and peripherals industries. This expansion is mirrored by growth in the numbers and types of users of networks, from the researcher to the home user.
Before the advent of computer networks that were based upon some type of telecommunications system, communication between calculation machines and early computers was performed by human users by carrying instructions between them. Many of the social behaviors seen in today's Internet were demonstrably present in the 19th century and arguably in even earlier networks using visual signals.
In September 1940, George Stibitz used a Teletype machine to send instructions for a problem set from his Model at Dartmouth College to his Complex Number Calculator in New York and received results back by the same means. Linking output systems like teletypewriters to computers was an interest at the Advanced Research Projects Agency (ARPA) when, in 1962, J.C.R. Licklider was hired and developed a working group he called the "Intergalactic Computer Network", a precursor to the ARPANET.
Early networks of communicating computers included the military radar system Semi-Automatic Ground Environment (SAGE), started in the late 1950s.
The commercial airline reservation system semi-automatic business research environment (SABRE) went online with two connected mainframes in 1960.[2][3]
In 1964, researchers at Dartmouth developed the Dartmouth Time Sharing System for distributed users of large computer systems. The same year, at Massachusetts Institute of Technology, a research group supported by General Electric and Bell Labs used a computer to route and manage telephone connections.
Throughout the 1960s Leonard Kleinrock, Paul Baran and Donald Davies independently conceptualized and developed network systems which used packets that could be used in a network between computer systems.
1965 Thomas Merrill and Lawrence G. Roberts created the first wide area network (WAN).
The first widely used telephone switch that used true computer control was introduced by Western Electric in 1965.
In 1969 the University of California at Los Angeles, the Stanford Research Institute, University of California at Santa Barbara, and the University of Utah were connected as the beginning of the ARPANET network using 50 kbit/s circuits.[4]
Commercial services using X.25 were deployed in 1972, and later used as an underlying infrastructure for expanding TCP/IP networks.
Today, computer networks are the core of modern communication. All modern aspects of the public switched telephone network (PSTN) are computer-controlled, and telephony increasingly runs over the Internet Protocol, although not necessarily the public Internet. The scope of communication has increased significantly in the past decade, and this boom in communications would not have been possible without the progressively advancing computer network. Computer networks, and the technologies needed to connect and communicate through and between them, continue to drive computer hardware, software, and peripherals industries. This expansion is mirrored by growth in the numbers and types of users of networks, from the researcher to the home user.
Computer network
Computer network
"Computer networks" redirects here. For the periodical, see Computer Networks (journal).
"Datacom" redirects here. For other uses, see Datacom (disambiguation).
Network science
Theory · History
Graph · Complex network · Contagion
Small-world · Scale-free ·
Community structure · Percolation · Evolution · Controllability · Topology · Graph drawing · Social capital · Link analysis · Optimization
Reciprocity · Closure · Homophily
Transitivity · Preferential attachment
Balance · Network effect · Influence
Types of Networks
Information · Telecommunication
Social · Biological · Neural · Semantic
Random · Dependency · Flow
Graphs
Vertex · Edge · Component
Directed · Multigraph · Bipartite
Weighted · Hypergraph · Random
Cycle · Loop · Path
Neighborhood · Clique · Complete · Cut
Data structure · Adjacency list & matrix
Incidence list & matrix
Metrics and Algorithms
Centrality · Degree · Betweenness
Closeness · PageRank · Motif
Clustering · Degree distribution · Assortativity · Distance · Modularity
Models
Random · Erdős–Rényi
Barabási–Albert · Watts–Strogatz
ERGM · Epidemic · Hierarchical
Browse
Topics · Software · Network scientists
Graph theory · Network theory
v t e
A computer network, often simply referred to as a network, is a collection of computers and other hardware components interconnected by communication channels that allow sharing of resources and information.[1] Where at least one process in one device is able to send/receive data to/from at least one process residing in a remote device, then the two devices are said to be in a network. Simply, more than one computer interconnected through a communication medium for information interchange is called a computer network.
Networks may be classified according to a wide variety of characteristics, such as the medium used to transport the data, communications protocol used, scale, topology, and organizational scope.
Communications protocols define the rules and data formats for exchanging information in a computer network, and provide the basis for network programming. Well-known communications protocols include Ethernet, a hardware and link layer standard that is ubiquitous in local area networks, and the Internet protocol suite, which defines a set of protocols for internetworking, i.e. for data communication between multiple networks, as well as host-to-host data transfer, and application-specific data transmission formats.
Computer networking is sometimes considered a sub-discipline of electrical engineering, telecommunications, computer science, information technology or computer engineering, since it relies upon the theoretical and practical application of these disciplines
"Computer networks" redirects here. For the periodical, see Computer Networks (journal).
"Datacom" redirects here. For other uses, see Datacom (disambiguation).
Network science
Theory · History
Graph · Complex network · Contagion
Small-world · Scale-free ·
Community structure · Percolation · Evolution · Controllability · Topology · Graph drawing · Social capital · Link analysis · Optimization
Reciprocity · Closure · Homophily
Transitivity · Preferential attachment
Balance · Network effect · Influence
Types of Networks
Information · Telecommunication
Social · Biological · Neural · Semantic
Random · Dependency · Flow
Graphs
Vertex · Edge · Component
Directed · Multigraph · Bipartite
Weighted · Hypergraph · Random
Cycle · Loop · Path
Neighborhood · Clique · Complete · Cut
Data structure · Adjacency list & matrix
Incidence list & matrix
Metrics and Algorithms
Centrality · Degree · Betweenness
Closeness · PageRank · Motif
Clustering · Degree distribution · Assortativity · Distance · Modularity
Models
Random · Erdős–Rényi
Barabási–Albert · Watts–Strogatz
ERGM · Epidemic · Hierarchical
Browse
Topics · Software · Network scientists
Graph theory · Network theory
v t e
A computer network, often simply referred to as a network, is a collection of computers and other hardware components interconnected by communication channels that allow sharing of resources and information.[1] Where at least one process in one device is able to send/receive data to/from at least one process residing in a remote device, then the two devices are said to be in a network. Simply, more than one computer interconnected through a communication medium for information interchange is called a computer network.
Networks may be classified according to a wide variety of characteristics, such as the medium used to transport the data, communications protocol used, scale, topology, and organizational scope.
Communications protocols define the rules and data formats for exchanging information in a computer network, and provide the basis for network programming. Well-known communications protocols include Ethernet, a hardware and link layer standard that is ubiquitous in local area networks, and the Internet protocol suite, which defines a set of protocols for internetworking, i.e. for data communication between multiple networks, as well as host-to-host data transfer, and application-specific data transmission formats.
Computer networking is sometimes considered a sub-discipline of electrical engineering, telecommunications, computer science, information technology or computer engineering, since it relies upon the theoretical and practical application of these disciplines
Free Proxy List (1 proxy per Country)
Free Proxy List (1 proxy per Country)
Free Proxy List (1 proxy per Country)
Afghanistan (1)
Albania (1)
Angola (1)
Argentina (1)
Armenia (1)
Australia (1)
Austria (1)
Bahamas (1)
Bahrain (1)
Bangladesh (1)
Barbados (1)
Belgium (1)
Benin (1)
Bolivia (1)
Brazil (1)
Bulgaria (1)
Cambodia (1)
Cameroon (1)
Canada (1)
Chile (1)
China (1)
Colombia (1)
Croatia (1)
Cyprus (1)
Czech Republic (1)
Denmark (1)
Ecuador (1)
Egypt (1)
Ethiopia (1)
Finland (1)
France (1)
Georgia (1)
Germany (1)
Greece (1)
Guatemala (1)
Honduras (1)
Hong Kong (1)
Hungary (1)
Iceland (1)
India (1)
Indonesia (1)
Iraq (1)
Ireland (1)
Israel (1)
Italy (1)
Japan (1)
Jordan (1)
Kazakstan (1)
Kenya (1)
Kuwait (1)
Kyrgyzstan (1)
Latvia (1)
Lebanon (1)
Lithuania (1)
Luxembourg (1)
Macedonia (1)
Malaysia (1)
Mali (1)
Malta (1)
Mexico (1)
Mozambique (1)
Namibia (1)
Nepal (1)
Netherlands (1)
Nicaragua (1)
Nigeria (1)
Norway (1)
Oman (1)
Pakistan (1)
Panama (1)
Paraguay (1)
Peru (1)
Philippines (1)
Poland (1)
Portugal (1)
Puerto Rico (1)
Romania (1)
Rwanda (1)
San Marino (1)
Saudi Arabia (1)
Senegal (1)
Sierra Leone (1)
Singapore (1)
Slovakia (1)
Slovenia (1)
South Africa (1)
Spain (1)
Sri Lanka (1)
Sudan (1)
Sweden (1)
Switzerland (1)
Taiwan (1)
Thailand (1)
Turkey (1)
Ukraine (1)
United Kingdom (1)
United States (1)
Uruguay (1)
Venezuela (1)
Vietnam (1)
Zimbabwe (1)
usa proxy
Free proxy lists United States (US). USA proxy servers.
Pages 0 1 2 3 Next page 265 proxies Permanent link to this page: http://spys.ru/free-proxy-list/US/
Proxy address:port Proxy type Anonymity* Country (city) Hostname Check date (GMT+04)
1 74.63.78.46:3128 HTTP HIA United States (Sacramento) server1.ezehost.com.au 01-jul-2012 10:36
2 64.37.63.106:8080 HTTP HIA United States (Orlando) ! mail.sketch2design.com 01-jul-2012 10:35
3 23.19.44.227:3128 HTTP HIA United States (Boston) booked.serratedsoftware.com 01-jul-2012 10:35
4 209.239.114.177:8082 HTTP HIA United States (Saint Louis) usloft1170.serverloft.com 01-jul-2012 10:35
5 216.255.86.100:80 HTTP HIA United States ! 216.255.86.100 01-jul-2012 10:35
6 64.150.190.57:8082 HTTP HIA United States (Lenexa) 64-150-190-57.dedicated.codero.net 01-jul-2012 10:35
7 74.208.64.128:8082 HTTP HIA United States (Wayne) ! 74.208.64.128 01-jul-2012 10:35
8 208.97.135.54:80 HTTP HIA United States (Trabuco Canyon) ! northcoastmag.com 01-jul-2012 10:34
9 174.137.184.37:8080 HTTP HIA United States (Garden City) barracks.webair.com 01-jul-2012 09:54
10 75.119.200.19:80 HTTP HIA United States (Brea) ! youthtogether.net 01-jul-2012 09:52
11 97.65.213.179:80 HTTP HIA United States (Indianapolis) 97-65-213-179.bluelock.com 01-jul-2012 09:51
12 66.197.193.197:8080 HTTP ANM United States (Scranton) g34.mailwallremote.com 01-jul-2012 04:44
13 69.64.56.159:44444 HTTP ANM United States (Saint Louis) usloft1453.serverloft.eu 01-jul-2012 04:44
14 72.64.146.135:3128 HTTP NOA United States ! static-72-64-146-135.tampfl.fios.verizon.net 01-jul-2012 04:44
15 76.73.26.78:3128 HTTP NOA United States (Denver) ! 76.73.26.78 01-jul-2012 04:44
16 76.73.26.75:3128 HTTP NOA United States (Denver) mail.mydtzone.com 01-jul-2012 04:44
17 97.81.243.20:8080 HTTP NOA United States (Sumiton) 97-81-243-20.dhcp.leds.al.charter.com 01-jul-2012 04:44
18 70.167.51.34:8080 HTTP NOA United States (Coffeyville) wsip-70-167-51-34.ks.ks.cox.net 01-jul-2012 04:44
19 72.167.88.72:80 HTTP HIA United States (Scottsdale) ! ip-72-167-88-72.ip.secureserver.net 01-jul-2012 04:44
20 198.145.120.198:3128 HTTP NOA United States (Vancouver) 198.145.120.198 01-jul-2012 04:44
21 199.30.59.171:3128 HTTP NOA United States (Bellefonte) vpbx.ajtel.net 01-jul-2012 04:44
22 184.172.6.156:3128 HTTP NOA United States (Houston) 184.172.6.156-static.reverse.networklayer.com 01-jul-2012 04:43
23 66.29.173.139:80 HTTP ANM United States (Heber City) 66.29.173.139.static.utbb.net 01-jul-2012 04:43
24 67.228.112.227:80 HTTP ANM United States (Seattle) ! 67.228.112.227-static.reverse.softlayer.com 01-jul-2012 04:43
25 173.248.139.218:80 HTTP NOA United States (Denver) 173.248.139.218 01-jul-2012 04:43
26 69.163.96.25:8080 HTTP HIA United States (Pacifica) unknown.blyon.com 01-jul-2012 04:43
27 76.27.185.253:36081 HTTP ANM United States (Chesterfield) c-76-27-185-253.hsd1.va.comcast.net 01-jul-2012 04:41
28 69.163.239.41:80 HTTP HIA United States (New York) ! tweakker.com 01-jul-2012 04:41
29 64.37.63.3:8080 HTTP HIA United States (Orlando) mail.sketch2design.com 01-jul-2012 04:40
30 173.45.229.233:8118 HTTP HIA United States (Saint Louis) ! 173-45-229-233.static.cloud-ips.com 01-jul-2012 04:40
*NOA - non anonymous proxy, ANM - anonymous proxy server, HIA - high anonymous proxy
Pages 0 1 2 3 Next page 265 proxies Permanent link to this page: http://spys.ru/free-proxy-list/US/
Proxy address:port Proxy type Anonymity* Country (city) Hostname Check date (GMT+04)
1 74.63.78.46:3128 HTTP HIA United States (Sacramento) server1.ezehost.com.au 01-jul-2012 10:36
2 64.37.63.106:8080 HTTP HIA United States (Orlando) ! mail.sketch2design.com 01-jul-2012 10:35
3 23.19.44.227:3128 HTTP HIA United States (Boston) booked.serratedsoftware.com 01-jul-2012 10:35
4 209.239.114.177:8082 HTTP HIA United States (Saint Louis) usloft1170.serverloft.com 01-jul-2012 10:35
5 216.255.86.100:80 HTTP HIA United States ! 216.255.86.100 01-jul-2012 10:35
6 64.150.190.57:8082 HTTP HIA United States (Lenexa) 64-150-190-57.dedicated.codero.net 01-jul-2012 10:35
7 74.208.64.128:8082 HTTP HIA United States (Wayne) ! 74.208.64.128 01-jul-2012 10:35
8 208.97.135.54:80 HTTP HIA United States (Trabuco Canyon) ! northcoastmag.com 01-jul-2012 10:34
9 174.137.184.37:8080 HTTP HIA United States (Garden City) barracks.webair.com 01-jul-2012 09:54
10 75.119.200.19:80 HTTP HIA United States (Brea) ! youthtogether.net 01-jul-2012 09:52
11 97.65.213.179:80 HTTP HIA United States (Indianapolis) 97-65-213-179.bluelock.com 01-jul-2012 09:51
12 66.197.193.197:8080 HTTP ANM United States (Scranton) g34.mailwallremote.com 01-jul-2012 04:44
13 69.64.56.159:44444 HTTP ANM United States (Saint Louis) usloft1453.serverloft.eu 01-jul-2012 04:44
14 72.64.146.135:3128 HTTP NOA United States ! static-72-64-146-135.tampfl.fios.verizon.net 01-jul-2012 04:44
15 76.73.26.78:3128 HTTP NOA United States (Denver) ! 76.73.26.78 01-jul-2012 04:44
16 76.73.26.75:3128 HTTP NOA United States (Denver) mail.mydtzone.com 01-jul-2012 04:44
17 97.81.243.20:8080 HTTP NOA United States (Sumiton) 97-81-243-20.dhcp.leds.al.charter.com 01-jul-2012 04:44
18 70.167.51.34:8080 HTTP NOA United States (Coffeyville) wsip-70-167-51-34.ks.ks.cox.net 01-jul-2012 04:44
19 72.167.88.72:80 HTTP HIA United States (Scottsdale) ! ip-72-167-88-72.ip.secureserver.net 01-jul-2012 04:44
20 198.145.120.198:3128 HTTP NOA United States (Vancouver) 198.145.120.198 01-jul-2012 04:44
21 199.30.59.171:3128 HTTP NOA United States (Bellefonte) vpbx.ajtel.net 01-jul-2012 04:44
22 184.172.6.156:3128 HTTP NOA United States (Houston) 184.172.6.156-static.reverse.networklayer.com 01-jul-2012 04:43
23 66.29.173.139:80 HTTP ANM United States (Heber City) 66.29.173.139.static.utbb.net 01-jul-2012 04:43
24 67.228.112.227:80 HTTP ANM United States (Seattle) ! 67.228.112.227-static.reverse.softlayer.com 01-jul-2012 04:43
25 173.248.139.218:80 HTTP NOA United States (Denver) 173.248.139.218 01-jul-2012 04:43
26 69.163.96.25:8080 HTTP HIA United States (Pacifica) unknown.blyon.com 01-jul-2012 04:43
27 76.27.185.253:36081 HTTP ANM United States (Chesterfield) c-76-27-185-253.hsd1.va.comcast.net 01-jul-2012 04:41
28 69.163.239.41:80 HTTP HIA United States (New York) ! tweakker.com 01-jul-2012 04:41
29 64.37.63.3:8080 HTTP HIA United States (Orlando) mail.sketch2design.com 01-jul-2012 04:40
30 173.45.229.233:8118 HTTP HIA United States (Saint Louis) ! 173-45-229-233.static.cloud-ips.com 01-jul-2012 04:40
*NOA - non anonymous proxy, ANM - anonymous proxy server, HIA - high anonymous proxy
Canada proxies
Proxy IP Proxy port Details
proxy 4 free :: xroxy proxies :: free proxy lists :: public proxy servers
Consider buying paid proxy subscription if you are tired of slow free proxies. Our proxies are fast and secure. Free trial is available!
64.15.144.85 3128 additional info
174.142.81.236 3128 additional info
174.142.81.238 3128 additional info
67.205.100.83 54321 additional info
70.38.69.9 1040 additional info
168.144.87.133 80 additional info
67.212.92.145 80 additional info
216.113.208.185 8081 additional info
67.205.100.81 54321 additional info
67.205.96.72 54321 additional info
proxy 4 free :: xroxy proxies :: free proxy lists :: public proxy
proxy 4 free :: xroxy proxies :: free proxy lists :: public proxy servers
Consider buying paid proxy subscription if you are tired of slow free proxies. Our proxies are fast and secure. Free trial is available!
64.15.144.85 3128 additional info
174.142.81.236 3128 additional info
174.142.81.238 3128 additional info
67.205.100.83 54321 additional info
70.38.69.9 1040 additional info
168.144.87.133 80 additional info
67.212.92.145 80 additional info
216.113.208.185 8081 additional info
67.205.100.81 54321 additional info
67.205.96.72 54321 additional info
proxy 4 free :: xroxy proxies :: free proxy lists :: public proxy
uk proxy
Proxy IP Proxy port Details
proxy 4 free :: xroxy proxies :: free proxy lists :: public proxy servers
Consider buying paid proxy subscription if you are tired of slow free proxies. Our proxies are fast and secure. Free trial is available!
87.236.211.13 8080 additional info
146.185.27.145 8080 additional info
217.20.245.59 80 additional info
217.36.19.178 3128 additional info
109.123.126.253 8080 additional info
81.199.34.100 8080 additional info
88.98.34.152 80 additional info
94.102.153.150 8888 additional info
146.255.9.124 3128 additional info
194.28.8.139 3128 additional info
146.185.27.146 8080 additional info
193.116.157.195 80 additional info
87.236.211.37 8080 additional info
proxy 4 free :: xroxy proxies :: free proxy lists :: public proxy servers
proxy 4 free :: xroxy proxies :: free proxy lists :: public proxy servers
Consider buying paid proxy subscription if you are tired of slow free proxies. Our proxies are fast and secure. Free trial is available!
87.236.211.13 8080 additional info
146.185.27.145 8080 additional info
217.20.245.59 80 additional info
217.36.19.178 3128 additional info
109.123.126.253 8080 additional info
81.199.34.100 8080 additional info
88.98.34.152 80 additional info
94.102.153.150 8888 additional info
146.255.9.124 3128 additional info
194.28.8.139 3128 additional info
146.185.27.146 8080 additional info
193.116.157.195 80 additional info
87.236.211.37 8080 additional info
proxy 4 free :: xroxy proxies :: free proxy lists :: public proxy servers
Proxylist 1::..
Proxy IP Proxy port Details
proxy 4 free :: xroxy proxies :: free proxy lists :: public proxy servers
Consider buying paid proxy subscription if you are tired of slow free proxies. Our proxies are fast and secure. Free trial is available!
209.62.12.130 8118 additional info
75.119.200.19 80 additional info
216.155.139.115 3128 additional info
64.37.63.3 8080 additional info
66.240.197.165 80 additional info
209.144.20.18 80 additional info
72.167.88.72 80 additional info
184.106.205.131 80 additional info
184.72.250.114 80 additional info
206.17.82.114 80 additional info
208.97.135.54 80 additional info
207.241.164.68 80 additional info
50.57.175.200 8080 additional info
50.57.175.200 81 additional info
66.146.193.31 8118 additional info
proxy 4 free :: xroxy proxies :: free proxy lists :: public proxy servers
Consider buying paid proxy subscription if you are tired of slow free proxies. Our proxies are fast and secure. Free trial is available!
209.62.12.130 8118 additional info
75.119.200.19 80 additional info
216.155.139.115 3128 additional info
64.37.63.3 8080 additional info
66.240.197.165 80 additional info
209.144.20.18 80 additional info
72.167.88.72 80 additional info
184.106.205.131 80 additional info
184.72.250.114 80 additional info
206.17.82.114 80 additional info
208.97.135.54 80 additional info
207.241.164.68 80 additional info
50.57.175.200 8080 additional info
50.57.175.200 81 additional info
66.146.193.31 8118 additional info
Updated in RealTime Free Proxy List: US Proxies (USA National domain).
Updated in RealTime Free Proxy List: US Proxies (USA National domain).
IP:Port
Host name Hosting country Proxy type Support HTTPS (SSL) Last good check
(hh:mm ago) Uptime % Average Response Time(ms) Check now Whois Smart
traceroute
206.64.92.16:8000
www.macs.net US
United States High anonymity N 15:17 3.392 32212 check whois traceroute
204.131.46.200:8000
user.rkymtnhi.com US
United States Transparent N 10:14 1.907 30005 check whois traceroute
66.167.100.59:6649
h-66-167-100-59.chcgilgm.covad.net US
United States High anonymity Y 09:18 7.158 10971 check whois traceroute
207.62.217.252:3128
Name unavailable US
United States Anonymous N 02:23 37.50 16717 check whois traceroute
216.49.160.27:80
proxy.islc.net US
United States Transparent N 09:44 0.925 9057 check whois traceroute
68.199.83.207:7212
ool-44c753cf.dyn.optonline.net US
United States Transparent N 14:57 0.315 7223 check whois traceroute
213.185.116.218:3128
Name unavailable US
United States Transparent na 21:29 9.130 9097 check whois traceroute
216.114.194.18:6588
216.114.194.18.hickorytech.net US
United States Transparent N 09:43 2.686 8426 check whois traceroute
209.247.51.196:80
ezboard.com US
United States Transparent N 13:51 0.474 2848 check whois traceroute
65.65.219.98:29122
adsl-65-65-219-98.dsl.rcsntx.swbell.net US
United States Anonymous N 09:49 5.921 8768 check whois traceroute
IP:Port
Host name Hosting country Proxy type Support HTTPS (SSL) Last good check
(hh:mm ago) Uptime % Average Response Time(ms) Check now Whois Smart
traceroute
206.64.92.16:8000
www.macs.net US
United States High anonymity N 15:17 3.392 32212 check whois traceroute
204.131.46.200:8000
user.rkymtnhi.com US
United States Transparent N 10:14 1.907 30005 check whois traceroute
66.167.100.59:6649
h-66-167-100-59.chcgilgm.covad.net US
United States High anonymity Y 09:18 7.158 10971 check whois traceroute
207.62.217.252:3128
Name unavailable US
United States Anonymous N 02:23 37.50 16717 check whois traceroute
216.49.160.27:80
proxy.islc.net US
United States Transparent N 09:44 0.925 9057 check whois traceroute
68.199.83.207:7212
ool-44c753cf.dyn.optonline.net US
United States Transparent N 14:57 0.315 7223 check whois traceroute
213.185.116.218:3128
Name unavailable US
United States Transparent na 21:29 9.130 9097 check whois traceroute
216.114.194.18:6588
216.114.194.18.hickorytech.net US
United States Transparent N 09:43 2.686 8426 check whois traceroute
209.247.51.196:80
ezboard.com US
United States Transparent N 13:51 0.474 2848 check whois traceroute
65.65.219.98:29122
adsl-65-65-219-98.dsl.rcsntx.swbell.net US
United States Anonymous N 09:49 5.921 8768 check whois traceroute
Usa proxy
| Checked proxy servers list | Server time: Sun, 01 Jul 12 10:49:43 +0400 | |||
| Proxy by ip:port | Proxy type | Anonymity | Country | Check date |
| 81.23.11.249:80 | HTTP | HIA | RU | 01-jul-2012 10:44 |
| 124.74.255.100:80 | HTTP | HIA | CN | 01-jul-2012 10:36 |
| 122.141.243.216:80 | HTTP | HIA | CN | 01-jul-2012 10:36 |
| 122.141.242.199:80 | HTTP | HIA | CN | 01-jul-2012 10:36 |
| 113.106.194.222:83 | HTTP | HIA | CN | 01-jul-2012 10:36 |
| 74.63.78.46:3128 | HTTP | HIA | US | 01-jul-2012 10:36 |
| 61.160.200.95:808 | HTTP | HIA | CN | 01-jul-2012 10:36 |
| 93.81.248.234:3128 | HTTP | HIA | RU | 01-jul-2012 10:36 |
| 64.37.63.106:8080 | HTTP | HIA | US | 01-jul-2012 10:35 |
| 23.19.44.227:3128 | HTTP | HIA | US | 01-jul-2012 10:35 |
| 209.239.114.177:8082 | HTTP | HIA | US | 01-jul-2012 10:35 |
| 216.255.86.100:80 | HTTP | HIA | US | 01-jul-2012 10:35 |
| 64.150.190.57:8082 | HTTP | HIA | US | 01-jul-2012 10:35 |
| 74.208.64.128:8082 | HTTP | HIA | US | 01-jul-2012 10:35 |
| 85.117.64.52:80 | HTTP | HIA | RU | 01-jul-2012 10:35 |
| 85.117.64.43:80 | HTTP | HIA | RU | 01-jul-2012 10:35 |
| 85.117.64.61:80 | HTTP | HIA | RU | 01-jul-2012 10:35 |
| 85.117.64.46:80 | HTTP | HIA | RU | 01-jul-2012 10:35 |
| 85.117.64.58:80 | HTTP | HIA | RU | 01-jul-2012 10:35 |
| 85.117.64.36:80 | HTTP | HIA | RU | 01-jul-2012 10:35 |
| 208.97.135.54:80 | HTTP | HIA | US | 01-jul-2012 10:34 |
| 85.234.38.157:3128 | HTTP | HIA | RU | 01-jul-2012 10:34 |
| 103.10.133.196:3128 | HTTP | NOA | IN | 01-jul-2012 10:13 |
| 174.137.184.37:8080 | HTTP | HIA | US | 01-jul-2012 09:54 |
Subscribe to:
Posts (Atom)