Hi Everyone,
The most basic aspect of networking that any administrator should be acquainted with is routing. Routing protocols are procedures for exchanging routing information between routers and making the routing decisions process as seamless as feasible. An autonomous system (AS) is a group of routers managed by a single entity, such as a company or organization. A routing domain is another name for an AS. A corporation's internal network and an ISP's network are both examples of an AS. The Internet is based on the AS paradigm, which necessitates the use of two types of routing protocols: Interior Gateway Protocols (IGPs) and Exterior Gateway Protocols (EGPs).
Interior Gateway Protocols (IGP):
IGPs are routing protocols that allow routers inside a single autonomous system to communicate routing information with one another (AS). Intra-AS routing is another name for it. In the internal networks, businesses, organizations, and even service providers use an IGP. An IGP is characterized as one of the following:
Open Shortest Path First (OSPF)
Routing Information Protocol (RIP)
Intermediate System to Intermediate System (IS-IS)
Enhanced Interior Gateway Routing Protocol (EIGRP)
Characteristics of IGP:
It's a distant vector IGP, which allows you to compare routes mathematically using a distance vector routing protocol. For this aim, this protocol makes use of some distance measurements.
Hold-downs are supported.
It makes use of composite matrices.
Makes use of multipath routing.
It facilitates the use of split horizons.
Supports load balancing with disparate costs.
Exterior Gateway Protocols (EGP):
EGPs are routing protocols that allow routers in different autonomous systems to exchange routing information. Inter-AS routing is another name for it. An EGP can be used to connect service providers and major corporations. Since they're in distinct systems, this process is usually more complicated and less common. The requirement for computer networks to communicate outside of their default systems can add to the complexity.
The Border Gateway Protocol (BGP) is the Internet's official routing protocol and is currently the only functional EGP. It's worth noting, though, that there is an EGP protocol called EGP. In the WAN, EGP was widely employed. It employs the InterAS (or Interdomain) routing protocol to exchange network reachability information across BGP routers. It utilizes the TCP protocol on port 179 to send routing messages. It's a protocol that uses distance vectors. The primary distinction between BGP and IGP is that, unlike IGP, BGP routing messages contain entire routes. The network administrators specify the routing policies.
EGPs include the following:
Border Gateway Protocol (BGP)
Exterior Gateway Protocol (EGP)
The ISO’s InterDomain Routing Protocol (IDRP)
BGP operation:
Two BGP routers are used to exchange data, which are called peers.
BGP routers send the entire routing table in the beginning.
The BGP router keeps the most recent version of all of its peers' BGP routing tables until the connection is terminated.
The updates are then delivered to the routing table as messages, which are used to change the routing table.
It provides a notification message if any unique circumstances or errors occur.
Thank You for reading.
