[Asterisk-Users] QoS What to do?
Andrew Kohlsmith
akohlsmith-asterisk at benshaw.com
Mon Oct 27 13:13:49 MST 2003
> Has anyone run * on a production system with voice and
> data.
Working on it. Mixed results so far.
> If a linux router is need can that run on the * box to
> reduce cost?
Outgoing is easy -- use lartc.org's script and do a little customization to
taste. My biggest problem has been incoming and my upstream ISP (MCI) --
it seems I get some pretty nasty ping times just going across the T1...
4-7ms normally but jumps to 200 on occassion. That's from my router to
theirs... nothing goofy, traffic averaging around 400kbps.
In order to try and keep the upstream router from queueing up a shitload of
traffic and bogging down VOIP, I have a strict policing policy in place on
my s0/0:
rate-limit input access-group 105 128000 65536 65536 conform-action
set-prec-transmit 5 exceed-action set-prec-continue 0
rate-limit input 1408000 8000 8000 conform-action transmit exceed-action
drop
Basically ACL105 is my VOIP ACL. Anything matching it under 128kbps should
get through without trouble (and get top precedence going through the
router). Everything not matching that, or exceeding that gets shaped to
1408kbps. That SHOULD keep the upstream router from plugging the link and
so far it seems ... alright. Not stellar, but alright. I'm sure if I
could convince them to do something similar on their end it would be a LOT
better.
I'm using LLQ on this 2610 which is what Cisco recommends for voice-type
traffic. My policy mapping looks like this:
class-map voice
match access-group 105
policy-map policy1
class voice
priority 96
class class-default
fair-queue
basically I'm giving anything matching my voice class 96kbps guaranteed on
outgoing, and letting everything else fight for what's left.
Regards,
Andrew
More information about the asterisk-users
mailing list