How are you aggregating WAN customers these days?

Andrew Koch andrew.koch at
Mon Jan 10 10:21:20 CST 2011

On Mon, Jan 10, 2011 at 09:28, Chris <behrnetworks at> wrote:
> The ASRs seem to be the consensus in a lot of places. Wondering if
> anyone has tried anything like aggregating T1 customers onto a mux
> box, then connecting that back to a 6500.
> What are the general impressions of the ASR series?
> On Mon, Jan 10, 2011 at 10:00 AM, Justin Wilson <lists at> wrote:
>>    Cisco ASR 1000. For T3 you can get a 4 port card.  Seems to perform well.
>>     Also have a 6500 deployed with some flexwan interfaces.  Believe this
>> will also work in the 7000 something chassis.

I would concur that the ASR1000 works well for channelized T3
aggregation.  We are currently phasing our 7600 series with SIP-200
cards and channelized T3 SPAs in favor of the ASR1000, using the same
SPAs, and have found them to perform well.  We found that the SIP-200
on the 7600 was incapable of handling PPP flapping as may occur when a
T1 is having facility trouble or looped back on itself.  In the 7600,
the SIP processes the PPP messaging, whereas the ASR SIP is a
passthrough to the RP for processing of PPP.  When the 7600 SIP starts
having trouble, it can cause the SIP to crash or even have the overall
PPP process on the whole box stop responding, needing to reload the
whole router.  It is possible that the beefier SIP modules on the 7600
would handle this better, but I have no experience with such.

Andrew Koch
andrew.koch at

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