pfSense » pfSense Packages

https://forum.netgate.com/topic/154741/squid-disable-multiple-sessions:
Hello, I want to set a server running pfsense with squid. I want to be sure that users aren't using the same login in different PCs or using proxy behind mine to permit access to more users than allowed.

from http://www.squid-cache.org/Doc/config/acl/:

acl aclname max_user_ip [-s] number
# This will be matched when the user attempts to log in from more
# than <number> different ip addresses. The authenticate_ip_ttl
# parameter controls the timeout on the ip entries. [fast]
# If -s is specified the limit is strict, denying browsing
# from any further IP addresses until the ttl has expired. Without
# -s Squid will just annoy the user by "randomly" denying requests.
# (the counter is reset each time the limit is reached and a
# request is denied)
# NOTE: in acceleration mode or where there is mesh of child proxies,
# clients may appear to come from multiple addresses if they are
# going through proxy farms, so a limit of 1 may cause user problems.