Configuring Network Address Translation
PR2000 Installation Guide
49
When a connection is started by a system in the local network to a system in
the global network, the PR2000 dynamically allocates a free global address
from the available ranges for the connection.
Inactivity timeout is the time to remove translations (de-allocate the global
address). There are individual configurable timeouts for UPD connections, DNS
connections, TCP connections, and TCP connections with FIN flag (no more
data from sender) or RST flag (reset connection) set.
Another NAT option is port translation. When port translation is enabled, the
same global IP address may be simultaneously used in more than one dynamic
translation. That is necessary when, for example, the hosts in a small LAN in a
small office/home office configuration share an unique IP address assigned to a
dialup connection. While allowing global IP address sharing, the use of port
mapping might limit the IP applications that can be used over the connection.
