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Cisco 1921

We manage a few sites where the customer rents office space. Part of this is they also sell the customer Internet connection. To do this we have a 40/100 Internet service in site and use bandwidth allocations to sell a customer either a contended or non contended service . We are moving from one Internet provider to another and we were going to supply the latest Cisco 2910 with 15.x firmware. Our new provider has said they don't think the 2921 will be sufficient to connect to a 100meg circuit. Has anyone had any issues with a 2921 being used in this scenario or should the 2921 be ok?

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Hall of Fame Super Gold

Re: Cisco 1921

Check attached document, however every case can be a little different.

New Member

Re: Cisco 1921

Sorry meant Cisco 1921 not 2921! Title of my query is correct just not the reference to it in my question!

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Super Bronze

Re: Cisco 1921


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Going by the Cisco performance documentation Paolo provided, and that you have asymmetrical bandwidth, you'll want to router that's good for about 75 Mbps (WAN) bandwidth.  So, according to this documentation, you would want a minimum of a 2951.

Cisco recommendation is based on 75% CPU utilization to support their recommendation for bandwidth.  As most don't drive their WAN links to 100% all the time, and the 75% does leave us a CPU cushion, you can often get by with a smaller device, perhaps 1 or 2 sizes smaller.  So laugh, you incorrect query text asking about a 2921 might be suitable, but your query header asking about about 1921 is likely much too small.


If the jump in price between a 1921 and a 2921 is a problem, you might consider a L3 switch if the hand-off is Ethernet, but beware a switch's lack of feature (e.g. most won't NAT).