The issue isn't so much a matter of "good or bad", but different.
The main aims are; continous, non-blocking downloads and smooth scanning of
dynamic and password protected HTTP traffic.
Many anti-virus programs now include a "proxy mail servier" which inserts
itself between your email program and mail server and pretends to be a mail
server. Instead of your mail program talking directly to the mail server, it
talks to your anti-virus program and the anti-virus program acts as a middle
man.
The most common problem is when (for whatever reason) the anti-virus proxy
server fails to respond to a request. Depending on the anti-virus program
being used, this could cause error messages such as "the server 127.0.0.1
could not be found" or "the server is not responding".
It appears that most/all anti-virus programs will be using a proxy at
sometime in the future.
For more information on Nod32's proxy server and reaction to it, see the
following;
http://www.wilderssecurity.com/showthread.php?t=192305
I am not an expert on the subject, so I am open to any corrections regarding
the above.
