Cisco Systems OL-4015-08 Add or Edit Dynamic Address Translation Rule: Outside to Inside

Chapter18 Network Address Translation
Network Address Translation Rules
18-26
Cisco Router and Security Device Manager Version 2.2 User’s Guide
OL-4015-08
Add or Edit Dynamic Address Translation Rule: Outside to Inside
Use this help topic when you have chosen direction From Outside to Inside in
the Add or the Edit Dynamic Address Translation Rule window.
Add or edit an address translation rule in this window. If you are editing a rule,
the rule type, static or dynamic, and the direction are disabled. If you need to
change these settings, delete the rule, and recreate it using the settings you want.
A dynamic address translation rule dynamically maps hosts to addresses, using
addresses included in a pool of addresses that are globally unique in the
destination network. The pool is defined by specifying a range of addresses and
giving the range a unique name. The configured router uses t he available
addresses in the pool (those not used for static translations or for its own WAN IP
address) for connections to the Internet or other outside network. When an address
is no longer in use, it is returned to the address pool to be dynamically assigned
to another device later.
Note If you create a NAT rule that would translate addresses of devices that are part of
a VPN, SDM will prompt you to allow it to create a route map that protects those
addresses from being translated by NAT. If NAT is allowed to translate addresses
of devices on a VPN, their translated addresses will not match the IPSec rule used
in the IPSec policy, and traffic will be sent unencrypted.
Direction
Select the traffic direction to which this rule applies.
From outside to inside
Select this option if you want to translate incoming addresses to addresses that
will be valid on your LAN. One situation in which you may want to do this is
when you are merging networks and must make one set of incoming addresses
compatible with an existing set on the LAN the router serves.
This help topic describes how the remaining fields are used when From outsi de to
inside is chosen.