[nsp] GSR Queueing Question

[Turpin Mark Contr AFCA/GCF]

> -----Original Message-----
> From: Dan Armstrong [mailto:dan at beanfield.com]
> Sent: Thursday, September 18, 2003 3:52 PM
> To: cisco-nsp at puck.nether.net
> Subject: [nsp] GSR Queueing Question
> 
> 
> I am having a moral crisis about ATM queuing on the 12000 
> GSR, and wonder if
> anybody has an opinion on this:

A moral crisis? :)

> Enter the GSR, no Per-VC queuing.  Does it still make sense 
> for me to set each
> customer's PVC up on the GSR at the subscribed rate (some 10, 
> some 100, some
> 1000)?  Or should I just set them all up UBR, and let the 
> switch & 1483/Lane card
> handle dropping frames that exceed the speed of the customer's port?
> 

I'd say use the switch.

> Will there be any negative impact on performance if one 
> customer gets whacked
> with traffic, and overrun some buffer?

Yes.

"Although it supports VBR-nrt traffic shaping, the 1xOC12 is 
recommended for use as a high-speed pipe in the network core.
The 1xOC12 does not support per-VC queuing and the 4xOC-3 card's
VC-isolation techniques like segmentation and reassembly (SAR) pools
and tx-queue-limits.  Thus, one congested VC can fill the packet
buffers shared by all other VCs configured on the same card.  Symptoms
of this problem include delayed and dropped packets."