Exterior gateway protocol

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An exterior gateway protocol is an IP routing protocol used to exchange routing information between autonomous systems. This exchange is crucial for communications across the Internet. Notable exterior gateway protocols include Exterior Gateway Protocol (EGP), now obsolete, and Border Gateway Protocol (BGP). [1] :188–189

By contrast, an interior gateway protocol is a type of protocol used for exchanging routing information between gateways (commonly routers) within an autonomous system (for example, a system of corporate local area networks). This routing information can then be used to route network-level protocols like IP. [1] :178

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<span class="mw-page-title-main">Routing protocol</span> Network protocol for distributing routing information to network equipment

A routing protocol specifies how routers communicate with each other to distribute information that enables them to select routes between nodes on a computer network. Routers perform the traffic directing functions on the Internet; data packets are forwarded through the networks of the internet from router to router until they reach their destination computer. Routing algorithms determine the specific choice of route. Each router has a prior knowledge only of networks attached to it directly. A routing protocol shares this information first among immediate neighbors, and then throughout the network. This way, routers gain knowledge of the topology of the network. The ability of routing protocols to dynamically adjust to changing conditions such as disabled connections and components and route data around obstructions is what gives the Internet its fault tolerance and high availability.

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IP routing is the application of routing methodologies to IP networks. This involves not only protocols and technologies but includes the policies of the worldwide organization and configuration of Internet infrastructure. In each IP network node, IP routing involves the determination of a suitable path for a network packet from a source to its destination in an IP network. The process uses static configuration rules or dynamically obtained from routing protocols to select specific packet forwarding methods to direct traffic to the next available intermediate network node one hop closer to the desired final destination, a total path potentially spanning multiple computer networks.

An interior gateway protocol (IGP) or Interior routing protocol is a type of routing protocol used for exchanging routing table information between gateways within an autonomous system. This routing information can then be used to route network-layer protocols like IP.

Federated VoIP is a form of packetized voice telephony that uses voice over IP between autonomous domains in the public Internet without the deployment of central virtual exchange points or switching centers for traffic routing. Federated VoIP uses decentralized addressing systems, such as ENUM, for location and identity information of participants and implements secure, trusted communications (TLS) for identify verification.

References

  1. 1 2 Hunt, Craig (2002). TCP/IP network administration (3 ed.). O'Reilly Media. ISBN   9781449391430. OCLC   52356435. Archived from the original on 1 July 2020. Retrieved 5 November 2021 via Dokuz Eylül University.