A list of ACL elements which, if matched, cause an ident
	(RFC 931) lookup to be performed for this request.  For
	example, you might choose to always perform ident lookups
	for your main multi-user Unix boxes, but not for your Macs
	and PCs.  By default, ident lookups are not performed for
	any requests.

	To enable ident lookups for specific client addresses, you
	can follow this example:

	acl ident_aware_hosts src 198.168.1.0/24
	ident_lookup_access allow ident_aware_hosts
	ident_lookup_access deny all

	Only src type ACL checks are fully supported.  A srcdomain
	ACL might work at times, but it will not always provide
	the correct result.

	This clause only supports fast acl types.
	See https://wiki.squid-cache.org/SquidFaq/SquidAcl for details.