In general, if you&#x27;re intentionally dropping packets it&#x27;s a firewall. NAT is just an address translator.<p>&gt; only the NAT process crosses<p>Nope, a router that doesn&#x27;t have a firewall but supports NAT will route a packet if it has the proper destination address. That is, if a packet is received that has a destination address of e.g. 192.156.1.2, it will be routed onto the LAN. However, this is a very <i>rare</i> configuration, as most routers (including ~all home routers) also include a firewall that does packet filtering.