An interior gateway protocol (IGP) or interior routing protocol is a type of
routing protocol
A routing protocol specifies how routers communicate with each other to distribute information that enables them to select paths between nodes on a computer network. Routers perform the traffic directing functions on the Internet; data packet ...
used for exchanging
routing table 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-layer protocols like
IP.
Interior gateway protocols can be divided into two categories:
distance-vector routing protocols and
link-state routing protocols. Specific examples of IGPs include
Open Shortest Path First
Open Shortest Path First (OSPF) is a routing protocol for Internet Protocol (IP) networks. It uses a link state routing (LSR) algorithm and falls into the group of interior gateway protocols (IGPs), operating within a single Autonomous syste ...
(OSPF),
Routing Information Protocol
The Routing Information Protocol (RIP) is one of the oldest distance-vector routing protocols which employs the hop count as a routing metric. RIP prevents routing loops by implementing a limit on the number of hops allowed in a path from so ...
(RIP),
Intermediate System to Intermediate System (IS-IS) and
Enhanced Interior Gateway Routing Protocol
Enhanced Interior Gateway Routing Protocol (EIGRP) is an advanced distance-vector routing protocol that is used on a computer network for automating routing decisions and configuration. The protocol was designed by Cisco Systems as a proprietary p ...
(EIGRP).
By contrast,
exterior gateway protocol
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 Gatewa ...
s are used to exchange routing information ''between'' autonomous systems and rely on IGPs to resolve routes within an autonomous system.
Examples
Examples of distance-vector routing protocols:
*
Routing Information Protocol
The Routing Information Protocol (RIP) is one of the oldest distance-vector routing protocols which employs the hop count as a routing metric. RIP prevents routing loops by implementing a limit on the number of hops allowed in a path from so ...
(RIP)
*
Routing Information Protocol Version 2 (RIPv2)
*
Routing Information Protocol Next Generation (RIPng), an extension of RIP version 2 with support for
IPv6
Internet Protocol version 6 (IPv6) is the most recent version of the Internet Protocol (IP), the communication protocol, communications protocol that provides an identification and location system for computers on networks and routes traffic ...
*
Interior Gateway Routing Protocol (IGRP)
*
Babel
Examples of link-state routing protocols:
*
Open Shortest Path First
Open Shortest Path First (OSPF) is a routing protocol for Internet Protocol (IP) networks. It uses a link state routing (LSR) algorithm and falls into the group of interior gateway protocols (IGPs), operating within a single Autonomous syste ...
(OSPF)
*
Intermediate system to intermediate system (IS-IS)
Advanced distance vector routing protocols have both the features of distance vector routing protocols and link-state routing protocols. One example is
Enhanced Interior Gateway Routing Protocol
Enhanced Interior Gateway Routing Protocol (EIGRP) is an advanced distance-vector routing protocol that is used on a computer network for automating routing decisions and configuration. The protocol was designed by Cisco Systems as a proprietary p ...
(EIGRP).
See also
*
Route analytics
Network monitoring is the use of a system that constantly monitors a computer network for slow or failing components and that notifies the network administrator (via email, SMS or other alarms) in case of outages or other trouble. Network monito ...
References
{{DEFAULTSORT:Interior Gateway Protocol
Routing protocols