Picking the right router for the load?

[Mike Mierzejewski]

I have talked to two Cisco Reps via our distributor and explained our network to them both and asked for suggested equipment. Our infrastructure has 4 circuits coming into the data center from our remote sites. Two of the circuits are cat5 and two are DS3. I want to use two routers to support two circuits each (cat5 and DS3). Each circuit is around 30Mb servicing around 13 locations with T1 connections, 55 locations in total. They suggested at a minimum the cisco 2951 model because we are utilizing one NM-1T3/E3 module in each router, and suggested getting the cisco 3925 model to cover future growth. I asked for a data sheet that has suggested models of routers for the bandwidth of the incoming pipes. The technicians said they would email this information over but twice now I have not received it and cannot find this information anywhere online. We currently have a cisco 2851 utilizing one NM-1T3/E3 module and they purchased a cisco 2911 to replace this unit.  

Any information or suggestions would be much appreciated

[paolo bevilacqua · Accepted solution]

A 2911 is to small. The 3925 or 3925E is the right recommendation.

See attached.

[Joseph W. Doherty]

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Posting

So if I understand you correctly, one router's routine load will be dual 30 Mbps, duplex.  That would be 120 Mbps, which if it was minimum size Ethernet would require a pps rate of 80 Kpps.  Multiply that by 4 to keep your average load at about 25%, and then you would want a box that offers about 320 Kpps.