In article ,
Tim+ writes:
Do they have a static IP address? I often wonder how they trace
downloads/uploads done via accounts that don't have fixed IP addresses.

Generally from the logs of DHCP servers, Radius servers, and the like
which will have known the mapping at the time.

However, there was recently a case where an ISP supplied wrong info to
the police, and the wrong people got their doors kicked in in the
middle of the night and all their computer equipment removed to search
for illegal images.

There seems to be a suggestion in this case that they used 2015 logs
to identify the addresses used in 2013.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]