IP Routing


Select from the following IP routing technologies for more in-depth information. Technology-specific resources available from these pages can assist you with network design, configuration, maintenance and operation, troubleshooting, and other related topics.
Border Gateway Protocol (BGP)
BGP performs interdomain routing in Transmission-Control Protocol/Internet Protocol (TCP/IP) networks. BGP is an exterior gateway protocol (EGP), which means that it performs routing between multiple autonomous systems or domains and exchanges routing and reachability information with other BGP systems.

Classless Interdomain Routing (CIDR)
Classless interdomain routing. IP addressing technique supported by BGP4 and based on route aggregation. CIDR allows routers to group routes together to minimize the quantity of routing information carried by the core routers.

Enhanced Interior Gateway Routing Protocol (EIGRP)
Enhanced IGRP provides compatibility and seamless interoperation with IGRP routers. An automatic-redistribution mechanism allows IGRP routes to be imported into Enhanced IGRP, and vice versa, so it is possible to add Enhanced IGRP gradually into an existing IGRP network.

Integrated Intermediate System-to-Intermediate System (IS-IS)
Intermediate System-to-Intermediate System. OSI link-state hierarchical routing protocol based on DECnet Phase V routing, whereby ISs (routers) exchange routing information based on a single metric, to determine network topology.

Interior Gateway Protocol (IGP)

Interior Gateway Routing Protocol (IGRP)
IGRP is a distance-vector interior gateway protocol (IGP). Distance-vector routing protocols call for each router to send all or a portion of its routing table in a routing-update message at regular intervals to each of its neighboring routers.

Multiprotocol BGP (MBGP)

On-Demand Routing (ODR)

Open Shortest Path First (OSPF)
Open Shortest Path First (OSPF) is a routing protocol developed for Internet Protocol (IP) networks by the interior gateway protocol (IGP) working group of the Internet Engineering Task Force (IETF).

Routing Information Protocol (RIP)
The Routing Information Protocol (RIP) is a distance-vector protocol that uses hop count as its metric. RIP is widely used for routing traffic in the global Internet and is an interior gateway protocol (IGP), which means that it performs routing within a single autonomous system.