View Single Post
Old 25-01-2009, 17:41   #117
broadbandbug
Inactive
 
Join Date: Aug 2007
Posts: 257
broadbandbug has a spectacular aura about thembroadbandbug has a spectacular aura about thembroadbandbug has a spectacular aura about thembroadbandbug has a spectacular aura about them
Re: 50Mbit Service Upstream Discussion

Quote:
Originally Posted by Turkey Machine View Post
To just expand on that, my modem is currently connected downstream to QAM256, the upstream is on QPSK. Judging by what I've read so far in this thread, that should more than qualify it for DOCSIS 2.0, heck DOCSIS 3 if the right modem's about.
The fact that your DS is QAM256 is nothing special, in fact that is defacto across the whole of VM with exception being the Bromley Platform that has a legacy STB that will not function at QAM256 and the DWDM areas of Langley.

DoCSIS 1.0 upstreams will support QPSK and QAM16, so your area either doesn't need the bandwidth to justify QAM16 or the area is too noisy to support it.

I have absolutely no idea why you think this would 'more than qualify it for DoCSIS 2.0'?

DoCSIS 2.0 brings in the ability to provide QAM32/64 in the upstream. However the network has to perform to specific noise characteristics to support it. With your area operating at QPSK, it is unlikely that in its current state it would support QAM16, let alone QAM32/64.

DoCSIS 3.0 is a totally different platform and the DS operate at EuroDoCSIS QAM256 and are channel bonded, so as you say a new modem.

For the upstream, it uses DoCSIS 2.0 technology at the moment anyway (no US channel bonding) so what I have said about D2.0 applies.
broadbandbug is offline   Reply With Quote