Quote:
|
Originally Posted by iadom
|
I have been involved in this VOIP discussion on another site that I frequent, I didn't notice there was also a discussion going on here about it.
BBKing would be the one to answer or comment on my understandings because I bow down to his superior IP and Docsis knowledge, but here goes as far as I understand the issues.
VOIP is a bolt on to the existing Cable modem Docsis system but requires the use of Docsis ver 1.1. ntl and Telewest currently use Docsis version 1.0, so as far as I understand it the system could not be implemented without an upgrade and changing out of the old CMX's if there are any left that will ot work on ver 1.1. The only exception to the rule would be original CWC areas because they alreay use Docsis ver 1.1, my understanding from a few years ago was that ver 1.0 only supports the transfer of data and not the timing aspects, this is OK for data but not for voice (data voice) as the timing is obviously critical.
I seem to remember (Perhaps correctly, perhaps not) that one of the enhancements for ver 1.1 was the implementation of a QOS facility (quality of service) this would allow the VOIP traffic to be given priority over general internet data, and I guess would slow down surfing and downloading for all the cable modem users not making VOIP calls.
The above info is as I remember it being described a few years ago when ntl started using the second phase cable modems, and I was also told at the same time that the Marconi/GPT system X switches had a bolt on facility to handle VOIP traffic, but I am not sure about the DMS100. I was suprised at this because I always thought the idea was to keep it away from the switch that was already working hard handling lots of SDH calls.
Please forgive me if any of the above is incorrect or inaccurate as I would stand corrected if anyone has any more recent info, or knows if ntl have been spending lots of their spare cash quietly upgrading to Docsis ver 1.1 in all areas.
Perhaps they already have a solution and are welcomng BT to use their network to provide cheap calls and take business away with open arms.
