I looked at the PG and they add in the calculation as I detailed in my most recent email. However, I am totally with you. The RTP/LLQ is different from the RSVP CAC and I would think that only a few extra Kbps would account for the RSVP control traffic in the PQ.
Jeff From: ccie_voice-boun...@onlinestudylist.com [mailto:ccie_voice-boun...@onlinestudylist.com] On Behalf Of Miron Kobelski Sent: Wednesday, January 05, 2011 10:49 AM To: Roig Borrell, Francesc Xavier Cc: ccie_voice@onlinestudylist.com; Shrini Subject: Re: [OSL | CCIE_Voice] RSVP LLQ priority value calculation Hi, RSVP reservation and actual LLQ usage are 2 different things. I think you should keep in mind, that there is no traffic in PQ before RSVP reservation completes. For RSVP calculation you only take into account L3. You have 2 possible bandwidth values: * standard (24kbps for G729/20ms) and * worst case (40 kbpbs for G729/10ms), because when the destination is ringing capabilities exchange has not yet occured and there is no media flow. That's why at this stage worst case is assumed (g729/40ms). PQ is still empty. As soon as the call is answered, capabilities are exchanged and decision about codec/payload is made -> reservation can be decreased to standard 24kbps (g729/20ms). Only now the RTP flow can occur -> PQ is filled up and served by LLQ (with values calculated including L2 overhead). One more thing - the task requirement is not very clear: RSVP traffic for me consists only of those several small RSVP protocol messages exchanged during RSVP negotiation. I'd not include RTP traffic in it... So I guess 5kbps should be more than enough. Anybody disagrees? HTH kobel On Wed, Jan 5, 2011 at 19:10, Roig Borrell, Francesc Xavier <francesc.ro...@tecnocom.es> wrote: Hi Shrini, Thank you for your answer. I don’t see very clear how you take into consideration L2 header These values 40kbps (g729 10ms)/ 24kbps (g729 20ms) only consider L3+UDP/RTP+Payload. For 2 g729 calls ip rsvp bandwith= 24+40 =64 OK But which value would you use for priority queue if you have this question Between HQ-BR1 provision enough bandwidth in the priority queue for 2 calls. Any RSVP traffic should be placed into the PQ. Ensure that you provision additional amount of bandwidth in the PQ to include RSVP traffic Thanks!! Francesc
_______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com
