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Re: What vexes VoIP users?


From: Scott Helms <khelms () ispalliance net>
Date: Wed, 02 Mar 2011 10:21:46 -0500


As I said, this second channel doesn't exist in almost all cases (its
not cost effective nor needed in almost all cases). Having said that
over the top VOIP providers do suffer in comparison because they don't
get the benefit of prioritization in the local cable plant.
"Cost-effective"?

Could you expand on how the provisioning of a second virtual pipe down
the hill to a cable box has any incremental costs at all?

Cheers,
-- jra



Because it takes either another 6 MHz on the downstream side that could be used for a TV channel as well as 3.2 MHz (or 6.4 MHz for >=D2) on the upstream side. It also takes the CMTS interfaces, which are not cheap even with the advent of high capacity cards & QAMs for D3. On top of all this it also takes more time on the design and management side because you have to make sure all of your nodes are getting both sets of channels and you have to make sure your provisioning or CMTS config keeps the EMTA's on the right channels.


--
Scott Helms
Vice President of Technology
ISP Alliance, Inc. DBA ZCorum
(678) 507-5000
--------------------------------
http://twitter.com/kscotthelms
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