Difference Between EIGRP and OSPF (With Table)

EIGRP and OSPF are two of the protocols with interior gateway routing. They help in selecting the routers for sharing and transferring the data through the interaction of routers. They are often used in varied situations for different performance or delays, speed, etc.  

Cisco, the leading network hardware manufacturer, made EIGR and occupies much of the market. But OSPF is used because it supports various manufacturers’ devices and strong standard protocol. The difference does not end here, there are many distinctions highlighted in this article. 

EIGRP vs OSPF 

The main difference between EIGRP and OSPF is that their scalability. EIGRP is vendor-specific and complicated and fails to migrate of vendor and leads to less scalability. On the other hand, OSPF is a simple and open standard protocol, and as a result, it can be scaled easily.  

The abbreviation for Enhanced Interior Gateway Routing Protocol is EIGRP. It is generally used to share the information which exists in the same region from one router to another one. EIGRP protocol is a complex one but can easily work in small and large networks. As it uses features of link-state routing protocol and distance vector route routing known as the hybrid protocol.  

The contraction of Open Shortest Path First is OSPF. It is a classless routing protocol and can be deployed and used in a variety of networks. It also assists discontiguous networks and VLSM or variable-length subnet masking. 

Comparison Table Between EIGRP and OSPF 

Parameters of Comparison

EIGRP

OSPF

Metric

Composite of bandwidth and delay

Cost

Type of routing

Advanced distance vector

Link state

Manual summarization

On all router

Only on ABRs and ASBRs

CPU requirements

Lower memory and CPU needs

High memory and CPU needs

Loop prevention

Split horizon and DUAL

Full knowledge of topology

What is EIGRP? 

EIGRP is a network-based protocol that lets routers exchange information more systematically compared to earlier network protocols BGP (Border Gateway Protocol) or IGRP (Interior Gateway Routing Protocol). In the 1990s, EIGRP grew out of the efforts of Cisco to address these protocols limitations.  

When tens of thousands of Cisco’s networks were connected by teleworker home offices, then the need grew for a scalable routing protocol. Cisco worked on a simple protocol that allows network administrators to assist shifting requirements without changing the routing design. As a result, it leads to the origin of EIGRP.  

EIGRP determines the most efficient routes to destinations that are reachable in a network of links and routers. It is the distance-based decision and whether there is a loop-free destination path. With faster convergences, it increases availability.  

This protocol uses a mechanism of reliable transport to guarantee all EIGRP packets ordered delivery to its neighbors. The intermixed transmission of unicast and multicast packets is supported by transport. HELLO, REPLY, UPDATE, QUERY, and REQUEST packets are five kinds of packages to facilitate session management and pass messages. 

What is OSPF? 

Routers connect networks with the help of IP or Internet Protocol, and OSPF is a router protocol to find the best path for packets by passing through connected networks set. This protocol is designated by the IETF or Internet Engineering Task Force as one of several IGPs or Interior Gateway Protocols.  

The OSPF has largely replaced the older RIP or Routing Information Protocol in corporate networks. RIP requires routers to send every 30 seconds of the entire routing table to neighbors. But OSPF sends only the changed part and only when a change occurs.  

Due to equipment failure, routes change the time it takes the routes of OSPF to find a path that is new between endpoints with no loops or called as open. As a result, it minimizes the path length is called the convergence time.  

RIP generally counts the router hops number between hosts on a network, OSPF simply bases choice of the path on “link states” that takes into account extra network information. OSPF has RIP support built-in for compatibility with older networks and for the router to host communication. 

Main Differences Between EIGRP and OSPF 

  1. EIGRP is vendor-specific and complicated and fails to migrate of vendor and leads to less scalability. In contrast, OSPF is a simple and open standard protocol, and as a result, it can be scaled easily.  
  2. For the multivendor environment, EIGRP is a good option because it does not require meticulous planning of the area. On the other hand, meticulous planning of the area is required in OSPF.  
  3. In terms of the unequal path load balancing feature, it is only supported by the EIGRP protocol. On the flip side, this feature is not supported on OSPF.  
  4. When it comes to backward compatibility with the older routers, the EIGRP is a preferable option compared to the OSPF.  
  5. Due to the usage of the DUAL algorithm in EIGRP where the alternative best path and the best path are selected and it can fall into the alternate best path if the best path goes wrong and that’s why has less convergence. But OSPF follows a different procedure and has a greater convergence time. 

Conclusion 

It can be concluded that EIGRP and OSPF are two of the protocols with interior gateway routing. EIGRP is vendor-specific and complicated and fails to migrate of vendor and leads to less scalability. On the flip side, OSPF is a simple and open standard protocol, and as a result, it can be scaled easily.  

When it comes to the type of routing, EIGRP is an advanced distance-vector, whereas OSPF is a link-state. EIGRP requires lower memory and CPU needs, while OSPF requires higher memory and CPU needs. Cisco is one of the leading network hardware manufacturers which lead to the creation of EIGRP and occupies much of the market. But OSPF is in usage because of the strong standard protocol and supports various manufacturers’ devices. 

References 

  1. https://escholarship.org/content/qt9h48b8x2/qt9h48b8x2.pdf
  2. http://www.hjp.at/doc/rfc/rfc2178.html