I had to check with the network guys to confirm, but pretty much the other guys in this thread have nailed it, so I don't have anything more to add apart from that it's great you have found a working solution.

Cheers!


I must also says thanks to the BigPipe people - even though it took a while they came back with a detailed response from the network guys.  I am glad that I managed to get this done without having to change ISP :-)