My cable modem ISP also have similar limitations. Their reason is
this: the cable modem that we use (Motorola CyberSURFR) is asymmetric
in terms of transfer speed. Uploading is much slower than
downloading, so the web server cannot serve requests as quickly.
Furthermore, while each user gets his/her own download "channel" (or
whatever that is they use), everyone shares the same upload channel
from the user to the cable company's office. That's why my ISP only
allows us to set up servers for "personal use". On the other hand,
a web server is set up at their office which is connected to the rest
of the world with fibre, so the limitation of the cable modem does not
apply.
I have no idea whether this is the same reason your ISP have these
restrictions, but it sounds similar to my situation.
Howard
-- Howard Cheng e-mail: hcheng@cs.ualberta.ca University of Alberta hcheng@gpu.srv.ualberta.ca MSc Computing Science URL : http://www.cs.ualberta.ca/~hcheng/Measure what is measurable, and make measurable what is not so. - Galilei Galileo