Standard firewall ruleset
i've installed pfsense today the first time and it works great. the question is, how is the standard-reaction of the firewall in case of packets which are going from wan to lan. there is no rule configured except the initial one.
If i understand you correctly :)
http://en.wikipedia.org/wiki/Stateful_firewall and under the hood http://www.openbsd.org/faq/pf/filter.html