Re: [Staffslug] Traffic shaping - anybody knowledgable on this?

I have a question that has arisen out of a discussion on another mailing list (fishing one).  I first need to make it known that I do not use peer to peer file sharing or newsgroups, no, honestly I really don't and haven't for possibly over 5 or 6 years now. So, I know it is possible to prioritise traffic at home via a router (main one that carries the ISP signal).  This is generally done by setting certain ports higher values (if that is the right way of describing it) so that they take priority over others.  But, can an ISP do the same for either individual customers or a blanket area or even everybody?  Further, can this (if it is possible) then be countermanded by an individual customer? I ask this because apparently Virgin Media customers find it increasingly difficult to access any peer to peer functions or newsgroups (Usenet) after 5pm due to traffic shaping on the part of virgin Media.  I am not a Virgin Media customer I'm with O2 but I would like opinions on this one please :-) No, not on being an O2 cutomer either as I'm quite happy with them.