packet out of state on a Pix

[admin_2]

What does the PIX do if it receives packets with a different source address to the destination address of the outbound packets of a specific connection.

I believe this is known as packets being 'out of state' or along those lines and was wondering if there was any configuration to avoid this.

My company network will be connecting to a third party network to exchange data and this is one scenario that has been foreseen in the event of certain hosts/devices being unavailable.

[#2]

It will fail. If the connection is formed inside to outside, the response (outside to inside) wont have an open translation so the packet is dropped.

If the connection is formed outside to inside, the pix will use NAT/Global if configured, to allow the outgoing session as a new session.

The receiving host should reject the response anyway, because it will receive a response from a different address to that from which it opened the connection.