If you use proxy authentication and the 'max_user_ip' ACL,
	this directive controls how long Squid remembers the IP
	addresses associated with each user.  Use a small value
	(e.g., 60 seconds) if your users might change addresses
	quickly, as is the case with dialup.   You might be safe
	using a larger value (e.g., 2 hours) in a corporate LAN
	environment with relatively static address assignments.