[cisco-voip] Cisco 871 - Voice over DMVPN

Wed Jul 29 23:30:48 EDT 2009

Matt,

I've been playing with ASA phone proxy phone from my house for several
months and never see any quality issues. I did however notice issues
with the predecessor product Cisco had before the ASA PP and I always
noticed issues. I think cisco is getting better at handling voice over
the internet.  

PS I have no special qos set up on either end -  6mb DSL home to 45 mb
inet connection.

Chris Osborne 

From: cisco-voip-bounces at puck.nether.net
[mailto:cisco-voip-bounces at puck.nether.net] On Behalf Of Matthew
Linsemier
Sent: Wednesday, July 29, 2009 11:18 AM
To: cisco-voip at puck.nether.net
Subject: [cisco-voip] Cisco 871 - Voice over DMVPN

Hey all,

I'm throwing this out again to see if anyone can offer some assistance.
If I should post in the DMVPN forum, I can do so as well, but I figured
I would start here.

I am in the process of refreshing my Cisco 871 router configurations
(5th build now ) and I was looking for some input in regards to
maintaining my voice quality the best I can over the Internet.  I have
been doing voice over IPSec for the last 5-6 years and it seems like it
never gets easier. :)

Right now we have about 35 users deployed remotely using Cisco 871W
routers and Cisco 7960 phones behind them.  They are connected to two
DMVPN hubs (for redundancy).  We have voice prioritized (among other
items) within the Tunnels and all works as expected (utilizing priority
queues, qos pre-classify, etc.).   

With the increase in home user bandwidth (10 meg / 12 meg) we are
starting to notice congestion on our 6 meg Internet link when large
amounts of data is sent or received over the tunnel Interfaces, which in
the end causes congestion, which in turn effects call quality.  We
utilize PacketShaper's on the internet links to prioritize IPSec
traffic, but when all the traffic is IPSec traffic, there are issues.  

I am looking into some possibilities of removing the voice traffic to
maintain call quality at all costs, and I have come up with a few ideas.

1.	Creating two DMVPN tunnels, one that carries only voice, and the
other that carries the rest of the data, and then using the PacketShaper
to guarantee bandwidth to the DMVPN tunnel that carries voice above all
other data. 
2.	Pulling the voice traffic out of the tunnel and using PhoneProxy
on the ASA's then utilizing PacketShaper to guarantee bandwidth to the
srtp session above all other data.

If anyone can throw out some pros and cons to either of these ideas, I
would like to hear them.  Also, if anyone knows of a better appliance
for managing QoS at the Internet level other than the PacketShaper, I
would like to hear that as well (outside of Cisco IOS QoS).

Thanks in advance,

Matt 

________________________________

CONFIDENTIALITY STATEMENT
This communication and any attachments are CONFIDENTIAL and may be
protected by one or more legal privileges. It is intended solely for the
use of the addressee identified above. If you are not the intended
recipient, any use, disclosure, copying or distribution of this
communication is UNAUTHORIZED. Neither this information block, the typed
name of the sender, nor anything else in this message is intended to
constitute an electronic signature unless a specific statement to the
contrary is included in this message. If you have received this
communication in error, please immediately contact me and delete this
communication from your computer. Thank you. 

________________________________

-----------------------------------------
Disclaimer:

This e-mail communication and any attachments may contain
confidential and privileged information and is for use by the
designated addressee(s) named above only.  If you are not the
intended addressee, you are hereby notified that you have received
this communication in error and that any use or reproduction of
this email or its contents is strictly prohibited and may be
unlawful.  If you have received this communication in error, please
notify us immediately by replying to this message and deleting it
from your computer. Thank you.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://puck.nether.net/pipermail/cisco-voip/attachments/20090729/aeeb8f92/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/gif
Size: 4171 bytes
Desc: image001.gif
URL: <https://puck.nether.net/pipermail/cisco-voip/attachments/20090729/aeeb8f92/attachment.gif>