Thread: Traffic Shaping
View Single Post
Old 05-04-2006, 19:12   #204
Chrysalis
cf.mega poster
 
Join Date: Sep 2003
Posts: 12,047
Chrysalis is cast in bronzeChrysalis is cast in bronzeChrysalis is cast in bronzeChrysalis is cast in bronze
Chrysalis is cast in bronze
Re: Traffic Shaping

Quote:
Originally Posted by James Henry
http://www.cableforum.co.uk/board/sh...5&postcount=11




In ntl 'Bromley' network areas this becomes:

8Mhz wide 64QAM downstream, symbol rate 6.592Msym/s @ 6b/sym = 38Mbps payload
8MHz wide 256QAM downstream, symbol rate 6.952Msym/s @ 8b/sym = 51Mbps payload.

This is per downstream, not per uBR, each area can be fed more than one downstream but ntl aren't doing this at this time (Telewest are).
Langley is the same as the TW specs I assume. I keep forgetting which I am but I think its langley. Has someone got the info for the bromley and langley areas?

Also why dont ntl make their entire network the same although it may cost a fair bit to rip out their langley stuff but having some people on 51mbps and others on 27 clearly is quite a difference some areas will have almost double the bandwidth available which probably explains the massive differences some people have with speeds. But once the network as a whole is all the same platform it ensures less of a postcode lottery so more fairness and no hassle of running 2 different platforms. Its a 2 tier service, customer A in area A might have digital tv services,VOD,10meg zipping along on a 51mpbs ubr and customer B in area B may have analogue tv, 10meg going at 1meg on a 27mbps ubr.
Chrysalis is offline   Reply With Quote