[ian@huth]

I don't think that Erol is looking quite correctly at the ammount of congestion one user can cause. He is saying that all users online at the same time cause an equal ammount oc congestion each. His analogy of raod use is very flawed if you look at it realistically. It is not the mileage that a driver does that causes congestion on the roads, it is the type of vehicle and how it is being driven that causes congestion.

If you take a UBR card that has 200 users on it you can have 190 of them online at the same time with no deterioration to any of their service if they are all just doing a little browsing and chatting. Along come the other ten users, all on 1Mb connections using p2p and having their upstreams maxed out by people downloading from them,. The result is deterioration in the service of all the users, some more than others. If ten of the original users go offline because of this congestion it will not improve matters for the 190 that are left. You can then rightly say that it is the ten 1Mb p2p users who are responsible for the congestion. Even if all the 190 original users went offline the remaining ten would suffer congestion and deterioration in service.

NTL broadband is a contended service and service levels will depend on who is online at any one time and what they are doing. A contended service relies on statistical diversity in the connected users and in what they are doing. If a number of users try to use the service like a leased line service and do their best to max out their downstream and more importantly their upstream then there is more of a chance of deterioration in service levels. In the case of p2p users who have their upstreams maxed out by people downloading from them and the card upstream becomes saturated by such use then it is mainly people that are not contributing to the finances of NTL that are causing problems for "normal" NTL users.