From: dunne.brian@adlittle.com
Date: Fri Nov 15 2002 - 00:41:18 GMT-3
FYI: The Layer 1-7 protocols of Voice networks over IP is usually (when
using H.323 ver 3/4):
Layer 7--Voice
Layer 6-Codec (G.711, G.723, G.729 etc.)
Layer 5-H.323 & related (Media Gateway to Gatekeeper or MG to MG
communication and authentication-signalling/call control over IP)
Layer 4- RTP (adds tagging) over UDP
Layer 3- IP
Layer 2-You name it
Layer 1- "
More than you want to know:
The "telco" networks that have performed Tandom offload often have MGCP (
and many variants and updates) or SIP at Layer 4/5 as well. Note that
Cisco has outsold the traditional Circuit-Switched Telco vendors (Lucent,
Siemens, Nortel, Alcatel, Ericsson) recently for all types of "voice"
equipment.
http://www.xdsl.com/content/backgroundinfo/papers/ -xDSL white
papers.
Regards-
"Chuck Church"
<cchurch@optonli To: "Joseph Rinehart" <jjrinehart@hotmail.com>, <ccielab@groupstudy.com>
ne.net> cc:
Sent by: bcc:
nobody@groupstud Subject: Re: VoIP over IDSL/SDSL
y.com
11/15/2002 08:48
AM
Please respond
to "Chuck
Church"
Joseph,
I assume you're xDSL connections are to the Internet. If they are,
there's not much difference between VoIP over that and any other physical
topology. Latency and bandwidth are your big variables over the Internet.
Do a traceroute and pings between your two proposed VoIP sites, and see
what
kind of ping times and hop counts you see. If the two sites are using the
same ISP in the same town, you should get good performance. But different
ISPs might mean 150 ms pings and 20 hops. Not real good for VoIP. CCO has
tons of articles about VoIP performance. Probably not many using xDSL, but
the same principals apply.
Chuck Church
CCIE #8776, MCNE, MCSE
----- Original Message -----
From: "Joseph Rinehart" <jjrinehart@hotmail.com>
To: <ccielab@groupstudy.com>
Sent: Thursday, November 14, 2002 4:40 PM
Subject: VoIP over IDSL/SDSL
> Strange topic I know but are there any white papers regarding the
viability
> and mechanics or doinf VoIP over IDSL and SDSL lines? Sounds goofy but
where
> would info be on something like this?
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