I think background noise of 12 - 25 Meg a day would worry me.

Especially as a port scan only uses several bytes, not kilobytes. Maintaining a connection doesn't take that much either, the odd ARP query at 60 bytes and maybe a DHCP request now and then. Certainly not in the megabyte range

As for port scanning, I would have thought that an ISP representative would have the knowhow to turn off icmp responses.

Granted.

From memory, I normally see about 600-800KB on a daily basis.

If you are a regular P2P users then it is possible what is using all the bandwidth is repeated attempts to access P2P resources that are no longer available. I know from the past when I used P2P that the attempted connections continued days after I stopped.

For reference, when I last checked (I can't check now as Sky do not give me the necessary info) it was around 3-4Mb, when there had been no P2P activity for months.

Well, I know what most of the background traffic I see on my connection relates to and I've no particular problem with it being there. It's not coming from the PlusNet network in the main either.

I wonder if people find their PlusNet firewall settings makes much of a difference?

Ian