1. Introduction

More often than not, as network administrators, we commonly come across routing protocols such as BGP and OSPF while designing and troubleshooting. This is because these routing protocols are the backbone of system communications.

In this tutorial, we’ll elucidate networking protocols, their types, and the major differences between EIGRP, OSPF, and BGP.

Without further ado, let’s get into the nitty-gritty details of it.

2. What Are Networking Protocols?

A network protocol is an established collection of rules and standards that help specify how data must be sent to and received from various devices. These protocols act as a common language for computer systems to communicate with each other. The Open System Interface (OSI) is the framework used to establish open communications between the systems. Amongst all protocols, TCP/IP [Transmission Control Protocol / Internet Protocol] is the most widely used in communication networks. It’s the set of layered protocols used for network communication.

Though most network traffic uses TCP/IP, other networking protocols do exist. To name a few: ICMP (Internet Control Message Protocol), IPSec (Internet Protocol Security), IGMP (Internet Group Management Protocol), etc.

Typically, consortiums like the IEEE (Institute of Electrical and Electronics Engineers), IETF (Internet Engineering Task Force), W3C (World Wide Web Consortium), ISO (International Organization for Standardization), and TU (International Telecommunications Union) will define and publish different network protocols that can be leveraged by the systems.

3. Network Routing Protocols

Routers are important backbone components for server-client communication because they help route network traffic between devices in the most efficient way. To identify the network’s shortest path, the router uses routing protocols. These protocols help the routers find the best path based on certain parameters and forward the user’s data.

The most well-known protocols include BGP, EiGRP, RIP, OSPF, and IS-IS:

Network Routing Protocols

4. Differences: EIGRP vs. OSPF vs. BGP

Attributes

EIGRP

OSPF

BGP

Name

Enhanced Interior Gateway Routing Protocol

Open Shortest Path First

Border Gateway Protocol

Method

Distance Vector Protocol

Link State Routing

Path Vector Protocol

Algorithm

DUAL (Diffusing Update Algorithm)

DIJKSTRA Algorithm

Best Path Algorithm

Type

Interior Gateway Protocol

Interior Gateway Protocol

Exterior Gateway Protocol

Hop Count

224 (100 default)

None

None

Classless

Yes

Yes

Yes

VLSM Support

Yes

Yes

Yes

Convergence Speed

Very Fast

Fast

Slow

Network Size

Large

Large

Very Large

Multicast IP

224.0.0.10

224.0.0.5, 224.0.0.6

NA

Port No

88

89

TCP 179

Vendor Compatibility

EIGRP was formerly a Cisco proprietary protocol; however, in 2013, Cisco declared EIGRP an open standard protocol compatible with all OEMs.

Yes

Yes

Global Routing Table Entry

The Letter “D” represents EIGRP

The Letter “O” represents OSPF

The Letter “B” represents BGP

Route Computation

To achieve quick convergence, EIGRP saves all routes rather than just the optimal one.

OSPF is based on link-state technology and computes the shortest path using the SPF algorithm.

This routing system often requires a very extensive Internet, and if it is employed, each router needs to have a sizable link-state database.

Administrative Distance

EIGRP 90 (Internal), 170 (External) is AD

110 AD

eBGP 20, iBGP 200 is AD

Metrics

Using bandwidth, reliability, load, and delay

Using bandwidth, cost

Using BGP attributes

Implementation

Basic Configuration is simple

Basic Configuration is simple

Easy to moderately difficult for basic configuration

Resource Consumption

Demands low CPU and memory

Demands high CPU and memory

Directly proportional to the size of the routing table

Usage

EIGRP’s only flaw is that it cannot be used for very long and can mostly work with Cisco software.

OSPF will be the dynamic routing protocol in use on the LAN unless a network is very tiny, out-of-date, or predominantly Cisco.

If the primary connection breaks, this protocol can be used to switch from one ISP link to another dynamically.

5. Conclusion

In this article, we’ve learned about the basic network routing protocols, which are the real backbone of the communication systems that exist today. The router uses these protocols for identifying the best routes and forwarding user traffic.

Further, we’ve also dove deeper into the distinctions between EIGRP, OSPF, and BGP. As we see, each routing protocol has its own advantages and disadvantages based on the network design and architecture. Many businesses may also deploy different routing protocols concurrently on the same network using route redistribution strategies.