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Information about Overlay Network

An overlay network is a computer network which is built on top of another network. Nodes in the overlay can be thought of as being connected by virtual or logical links, each of which corresponds to a path, perhaps through many physical links, in the underlying network. For example, many peer-to-peer networks are overlay networks because they run on top of the Internet. Dial-up Internet is an overlay upon the telephone network.

Uses of overlay networks

Overlay networks can be constructed in order to permit routing messages to destinations not specified by an IP address. For example, distributed hash tables can be used to route messages to a node having specific logical address, whose IP address is not known in advance.

Overlay networks have also been proposed as a way to improve Internet routing, such as through quality of service guarantees to achieve higher-quality streaming media. Previous proposals such as IntServ, DiffServ, and IP Multicast have not seen wide acceptance largely because they require modification of all routers in the network. On the other hand, an overlay network can be incrementally deployed on end-hosts running the overlay protocol software, without cooperation from ISPs. The overlay has no control over how packets are routed in the underlying network between two overlay nodes, but it can control, for example, the sequence of overlay nodes a message traverses before reaching its destination.

For example, Akamai Technologies manages an overlay network which provides reliable, efficient content delivery (a kind of multicast). Academic research includes End System Multicast and Overcast for multicast; RON (Resilient Overlay Network) for resilient routing; and OverQoS for quality of service guarantees, among others.

List of overlay network protocols

References

External links

as a college campus, industrial complex, or a military base. A CAN, may be considered a type of MAN (metropolitan area network), but is generally limited to an area that is smaller than a typical MAN.
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A node is a device that is connected as part of a computer network. For example, a node may be a computer, personal digital assistant, cell phone, router, switch, or hub.
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peer-to-peer (or "P2P") computer network exploits diverse connectivity between participants in a network and the cumulative bandwidth of network participants rather than conventional centralized resources where a relatively low number of servers provide the core value to a
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Internet is a worldwide, publicly accessible series of interconnected computer networks that transmit data by packet switching using the standard Internet Protocol (IP). It is a "network of networks" that consists of millions of smaller domestic, academic, business, and government
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Routing (or routeing) is the process of selecting paths in a network along which to send data or physical traffic. Routing is performed for many kinds of networks, including the telephone network, the Internet, and transport networks.
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An IP address (Internet Protocol address) is a unique address that certain electronic devices use in order to identify and communicate with each other on a computer network utilizing the Internet Protocol standard (IP)—in simpler terms, a computer address.
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Distributed hash tables (DHTs) are a class of decentralized distributed systems that provide a lookup service similar to a hash table: (name, value
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Routing (or routeing) is the process of selecting paths in a network along which to send data or physical traffic. Routing is performed for many kinds of networks, including the telephone network, the Internet, and transport networks.
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Quality of Service, abbreviated QoS, refers to resource reservation control mechanisms. Quality of Service can provide different priority to different users or data flows, or guarantee a certain level of performance to a data flow in accordance with requests from the
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In computer networking, IntServ or integrated services is an architecture that specifies the elements to guarantee quality of service (QoS) on networks. IntServ can for example be used to allow video and sound to reach the receiver without interruption.
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DiffServ or Differentiated Services is a computer networking architecture that specifies a simple, scalable and coarse-grained mechanism for classifying, managing network traffic and providing quality of service (QoS) guarantees on modern IP networks.
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IP Multicast is a method of forwarding IP datagrams to a group of interested receivers. See the article on multicast for a general discussion of this subject - this article is specifically about IP Multicast.
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router is a device that extracts the destination of a packet it receives, selects the best path to that destination, and forwards data packets to the next device along this path.[1] They connect networks together; a LAN to a WAN for example, to access the Internet.
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Internet service provider (abbr. ISP, also called Internet access provider or IAP) is a business or organization that provides consumers or businesses access to the Internet and related services. In the past, most ISPs were run by the phone companies.
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Akamai Technologies, Inc.

Public (NASDAQ:  AKAM )
Founded 1998
Headquarters Cambridge, Massachusetts, United States

Key people George H. Conrades, Chairman
Paul L.
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Multicast is the delivery of information to a group of destinations simultaneously using the most efficient strategy to deliver the messages over each link of the network only once, creating copies only when the links to the destinations split.
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Coordinates: Ron is a panchayat town in Gadag district in the Indian state of Karnataka.

Of historical importance, called Dronapur in ancient times. There are temples built by ancient architect Dronacharya.
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Distributed hash tables (DHTs) are a class of decentralized distributed systems that provide a lookup service similar to a hash table: (name, value
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peer-to-peer (or "P2P") computer network exploits diverse connectivity between participants in a network and the cumulative bandwidth of network participants rather than conventional centralized resources where a relatively low number of servers provide the core value to a
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Gnutella (pronounced: /nʊˈtɛlə/ with a silent g, or alternatively /gnʊˈtɛlə/) is a file sharing network.
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Maintainer: Ian Clarke

OS: Cross-platform

Use: Anonymity, Peer to peer, Friend to friend
License: GNU General Public License
Website: [1]

In computer science, Freenet
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I2P (originally short for Invisible Internet Project,[1] though it is not commonly referred to by this name anymore) is a free and open source project building an anonymous network (or, more accurately, a pseudonymous overlay network).
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France Télécom

Public (Euronext: FTE , NYSE:  FTE )
Founded 1988 (spun off from governmental control)
Headquarters Paris, France

Key people Didier Lombard, Chairman & CEO
Industry Telecommunications
Products Communication services
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Internet Relay Chat (IRC) is a form of real-time Internet chat or synchronous conferencing. It is mainly designed for group (many-to-many) communication in discussion forums called channels, but also allows one-to-one communication and data transfers via private message.
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Robert Tappan Morris (rtm, born 1965) is an associate professor at Massachusetts Institute of Technology. He is best known for creating the Morris Worm in 1988, considered the first computer worm on the Internet.
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The USENIX Association is the Advanced Computing Technical Association. It was founded in 1975 under the name "Unix Users Group", focusing primarily on the study and development of Unix and similar systems.
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Dr. Randy H. Katz is a distinguished professor at University of California, Berkeley of the Electrical Engineering and Computer Science Department. Katz received a A.B. from Cornell University (May 1976), MS from UC Berkeley (June 1978), and Ph.D.
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