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New Member

Campus Design - Layer 3 - OSPF or EIGRP

I am in the process of designing a campus , 2 catalyst 6513 and 2 catalyst 4006 - I have catalyst 2900/1900 connected to the switches. I want to configure layer 3 between the 4006 and the 6500 - fully meshed with dual gigabit links between them. I will configure each link on its own vlan with a mask of - 7 vlans for this. I need to know wheter to use EIGRP or OSPF on the whole network or configure OSPF on the gigabit (L3) links and EIGRP on the switches (for the vlans) - redistribute EIGRP into OSPF. Can I use only EIGRP?Can I use only OSPF?Or can I use both.

New Member

Re: Campus Design - Layer 3 - OSPF or EIGRP


Re: Campus Design - Layer 3 - OSPF or EIGRP

Technical reasons aside, a lot of this has to do with personal preference and comfort level with either EIGRP or OSPF. Both will do the job well. EIGRP is easy to implement and takes less thought. Take that for what you want.

Now for the technical reasons:

-EIGRP is proprietary to cisco, OSPF is an IETF standard

-EIGRP scales well, takes less memory and CPU. Might be a consideration if running on low end routers.

-OSPF can scale slightly better in larger environments due to areas and based on implementers design.

-EIGRP has also better load balancing tweaks compared to OSPF

-both support secure transmition - message-digest key

-OSPF takes more knowledge to implement well (DR, areas, NBMA, LSAs)

-Both can summarize, EIGRP can anywhere on any interface

-Use different timers, which can be tweaked but that can lead to errors and troubleshooting.

Conclusion: both will do the job very well. But don't redistribute unless you have to, adds complexity and troubleshooting that you can do without.

Pick one and use only one based on your comfort level with the protocol and consider the points above.

Hope that helps.


New Member

Re: Campus Design - Layer 3 - OSPF or EIGRP

Keep it as simple as possible!

You can easily handle this with just one routing protocol, be it either OSPF or EIGRP.

Which one to use is really a matter of taste (and for some perhaps religion as well?). EIGRP is probably a little easier to deploy than OSPF, but EIGRP can break miserably in large networks. EIGRP is also a Cisco proprietary protocol. Personally I prefer OSPF, because it forces you to think a little more about your design BEFORE deployment.

I suggest reading the OSPF design guide: