Most places I have been at where this is allowed have the policy that
only company equipment can be allowed to connect in. Thus they can
purchase licenses and maintain the system that connects (usually being a
laptop) and prevent such things as trojans and viruses from existing.
The basic thought is that while some users might be savvy enough to know
how to protect themselves, most are not and/or just do not. Therefore
it is a big risk to allow non-company equipment to connect.
--
David M. Fetter - http://www.fetterconsulting.com/
"The world is full of power and energy and a person can go far by just
skimming off a tiny bit of it." Neal Stephenson - Snow Crash