Top 5 Network Routing Protocols Explained

A vast number of diverse network protocols exist to enable computers to communicate with each other and with different types of devices. Routing protocols are groups of system protocols that allow network routers to connect and logically convey traffic between the corresponding networks. All protocols presented below each facilitate this crucial function of computer networking and routers.

The Way Routing Protocols Function

All network routing protocols execute three basic tasks:

  1. Discovery – identifying the other routers in the network.
  2. Route management – observe all potential destinations of network messages as well as some information defining the pathway for each.
  3. Path specification – make effective judgments where to send network messages.

Two kinds of routing protocols:

  1. Link-State Protocols – create and monitor an entire map of the existing network links in an area.
  2. Distance-Vector Protocols – enable routers to function with fewer data regarding the network zone.

Five Leading Routing Protocols

1. Routing Information Protocol (RIP)

Researchers developed RIP almost 40 years ago for application on small and medium interior networks that linked to initial versions of the internet. RIP can route messages through networks with a maximum limit of 15 hops. (A hop denotes one part of the whole path between a source point and destination point).

RIP-capable routers find a particular network by initially sending a message querying router matrices from nearby devices. The nearest routers processing RIP reply by returning the complete routing matrices to the requesting router, at which point the requestor adheres to a process to incorporate these changes into its array.

At predetermined periods, RIP routers will regularly send out their router matrices to the neighboring counterparts so that all updates can be disseminated throughout the network.

2. Open Shortest Path First (OSPF)

The OSPF was generated to surmount some of RIP’s limitations that include the following:

It was restricted to 15 hop counts. Failure to categorize networks into routing levels, essential for performance, and manageability on extensive internal systems. Substantial increases in network traffic that are caused by frequently re-sending complete router matrices at predetermined intervals.

As its name implies, OSPF is a public model with widespread acceptance across several industry manufacturers. OSPF routers detect the network by sending ID messages to one another, followed by information capturing particular routing data in place of the whole routing package. It is the only routing protocol of its kind included in this group.


Cisco created Internet Gateway Routing Protocol as an option to Routing Information Protocol. The more recent Enhanced IGRP (EIGRP) rendered IGRP outdated in the last decade of the 20th century. EIGRP enhances the efficiency of the routing algorithms and maintains classless IP subnets more effectively than older IGRP. EIGRP does not require routing orders.

Developed as a proprietary procedure compatible exclusively with Cisco devices, Enhanced IGRP was designed with the objectives of uncomplicated configuration and enhanced performance compared to OSPF protocol.

4. IS-IS

The Intermediate System to Intermediate System protocol works in the same way as OSPF. Although OSPF is the overall popular choice, IS-IS remains in extensive use by ISPs that have profited because the protocol is more adaptable to the specialized settings. Different from other protocols in this group, IS-IS utilizes the Internet Protocol (IP) addressing system.

5. Border Gateway Protocol (BGP) and External Gateway Protocol (EGP)

The BGP is currently the Internet standard EGP. BGP senses alterations to routing matrices and discriminatingly conveys those updates to related routers.

ISPs typically use BGP to link networks together. Furthermore, larger businesses occasionally use BGP to link several internal systems. Professionals regard BGP as the most perplexing among routing protocols because of its complex configuration.

Additional information and definitions

Older RIP accommodated only IPv4 networks, but the more recent RIPng standard also sustains IPv6. RIP uses either UDP ports 520 or 521 (RIPng) for its communication.

  • IPv4 is Internet Protocol version 4 – an example would be
  • IPv6 is Internet Protocol version 6 – an example would be 1abc.1000.2000.3.400.d5dd.de11.67cf

UDP or User Datagram Protocol is one of the oldest existing protocols. Although UDP has become somewhat unreliable compared to newer protocols, it still has functions that modern protocols such as TCP cannot match. UDP is being used in real-time gaming and video conferencing applications.

Emil S.

Emil is a Data & Design Specialist with a degree in BS Information System, specializes in Admin Support & Creative Design.

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