Airscanner Mobile Firewall for Windows Mobile Pocket PC is a low-level, bi-directional, packet filtering firewall that examines all incoming and outgoing traffic to ensure it is permitted based on access control lists that are selected from a set of predefined filters, or from filters manually created by a user. The firewall parses packets as they come in (or go out) on the wire and matches the data against a ruleset of ports or IP addresses, URLs, etc. Airscanner Mobile Firewall is a true, full strength NDIS firewall requiring a custom-written packet driver.