ADSL Implementation

I have a vague understand on how ADSL works at the exchange, but I'm curious how it works in conjunction with a LLU provider, specifically - talktalk.

Would anyone mind explaining for me the backhaul process? and also label to whom the equipment belongs and is therefore rented from?

Something like: End user <- Phoneline (BT) <- DSLAM etc

Thanks in advance. Just curious as to how it all works, and thought this would be the best place to ask

Companies don't make that information public but I can make a guess.

For TalkTalk LLU:
EU<-Phone Line->TT MSAN<->BT Backhaul<->TalkTalk Network<->TalkTalk

For TalkTalk IPStream:
EU<-Phone Line->BT DSLAM<->BT Backhaul<->BT Network<->TalkTalk

The area I'm lacking information about is 'BT Backhaul' for LLU. It depends whether TalkTalk have backhaul out of the exchange or not. I've always assumed that most exchanges only have BT cabling so the first few kilometres will be on BT's backhaul. Although since TalkTalk will have ordered the capacity you could perhaps call it 'TalkTalk backhaul over BT cables'. I'm calling it BT backhaul on the grounds that BT are responsible for maintaining the link. I would expect that LLU operators use BT's BES product:

http://www.openreach.co.uk/orpg/products/ethernet/be...

Edited by Andrue (Fri 21-Aug-09 08:10:37)

Backhaul is very much down to the individual operator at any particular exchange. Most will Opt for Openreach Ethernet services but some, e.g. Easynet have used their own backhaul direct into the exchange .
For this they use an Openreach service called Cablelink whch connects the LLU operators fibre into the exchange building.