Re: OT? cRTP header compression

["Thomas Kernen" <tkernen () deckpoint ch>]

Hi Antonio,

Agreed with all the info you mention below, I am only talking about RTP
vs cRTP usage on diff series, does anyone have info with the CPU uage vs
the number of calls/sessions/DS0s sent accross the link that has header
compression enabled?
All the rest related to QoS, Link Fragmentation, packet size and so on
has been covered.

Thomas

----- Original Message -----
From: "Pena, Antonio" <Antonio_Pena () verestar com>
To: "'Thomas Kernen'" <tkernen () deckpoint ch>; <nanog () merit edu>
Sent: Wednesday, April 10, 2002 11:55 PM
Subject: RE: OT? cRTP header compression


> Hello Thomas
>
> I had some kind of experience doing cRTP over Cisco routers, we use
Cisco
> 7204 & 7206 Routers on the IP Gateways and Cisco's 3600 and 5300 as
VoIP
> gateways, as well we had a small setup using a Cisco 2611 router on
the
> termination router.
>
> The trick is change the VoIP payload size of each packet to reduce the
> packets per second in a half improving the  performance over the
routers,
> also we are using as Cisco recommends TCP & RTP headers compression
over the
> circuits using only MLPPP encapsulation.
>
> Also please note that using cRTP and Compression you have increased
the
> switching delay over the circuit and for that reason you may need also
to
> have more processing power of the router.
>
> Below you can see a Cisco site where you can check the recommendations
for
> this setup and also based on that information I created a Bandwidth
> calculator on an excel sheet, if you want it, just drop me an email, I
will
> send it you.
>
> http://www.cisco.com/warp/public/788/voice-qos/voip-mlppp.html
http://www.cisco.com/warp/public/788/pkt-voice-general/bwidth_consume.ht
ml
>
http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122cgcr/
fqos
> _c/fqcprt6/qcfcrtp.htm
>
> http://www.cisco.com/warp/public/105/compression-qos.html
>
>
>
> Bye
>
> Antonio J. Pena
> Manager, Network Engineering
>
> (  /_ _ _  __/_ _
> |_/(-/ (-_) /(//
> Verestar, inc.
> 1901 Main street
> Santa Monica, CA, 90405
> Phone(310)382-3300
> Direct(310)382-3409
> antonio_pena () verestar com
> http://www.verestar.com
>
>
> -----Original Message-----
> From: Thomas Kernen [mailto:tkernen () deckpoint ch]
> Sent: Wednesday, April 10, 2002 1:11 PM
> To: nanog () merit edu
> Subject: OT? cRTP header compression
>
>
>
>
> I'm looking for real world experience related to deploying cRTP header
> compression on Cisco routers related to VoIP flows. We are trying to
> evalute what type of hardware (ie: CPU power since cRTP is CEF
switched
> since 12.2x IIRC) is required to handle 96/192/384 VoIP calls over a
> single circuit (HDLC/PPP/FR). This is related to specific overseas
> circuits where the cost of the circuit is still very expensive vs the
> cost for the extra hardware to handle the header compression. I'm
> disregarding all QoS info at this stage.
>
> Cheers
> Thomas