impact of OSPF authentication on performance

[amir_f_b]

Hi All,

Is there any influence on router performance when using OSPF authentication clear/MD5?

Thanks.

Amir.

[networker123]

I did this before and using Cisco 2651XM router. 6 links running OSPF with authentication MD5, the routers hanged.But, After I disable the authenticatiion,everything work fine. But,I don't encourage you to use it. Though interfaces that you don't want it to learn advertise any route using OSPF, just put "passive-interface"command.

[vcjones]

Not sure what went wrong for networker123, I've been using OSPF authentication on exposed links for years. The CPU impact is generally minimal (the limiting factor with OSPF is the SPF tree calculation, which is required whenever a link changes state, not the packet parsing). No noticeable performance impact even on a 2500 series router.

Given the security challenges today, I avoid the use of any protocols which lack strong authentication on any network where I can't trust all devices. The last thing I need on a high availability network is for a Windows worm to be able to turn a local PC into a routing zombie which comes across as the best route to everywhere.

Good luck and have fun!

Vincent C Jones

www.networkingunlimited.com

P.S. Depending upon what "the routers hanged" means, it sounds more like an IOS bug or configuration screwup than a problem with OSPF authentication.

[kmchoong]

I experienced the same thing as compare to networker123 before, the routers that I was using are the combination of 2500,2600 and 1700 series. No sure whether it is IOS bug.Too bad, no luck to make it work.