Cisco ASA Series Cli Configuration Manual page 841

Chapter 1 Configuring Twice NAT
Table 1-1 Feature History for Twice NAT (continued)
Feature Name
Round robin PAT pool allocation uses the same
IP address for existing hosts
Flat range of PAT ports for a PAT pool
Extended PAT for a PAT pool
Platform
Releases Feature Information
8.4(3) When using a PAT pool with round robin allocation, if a host
has an existing connection, then subsequent connections
from that host will use the same PAT IP address if ports are
available.
We did not modify any commands.
This feature is not available in 8.5(1) or 8.6(1).
8.4(3) If available, the real source port number is used for the
mapped port. However, if the real port is not available, by
default the mapped ports are chosen from the same range of
ports as the real port number: 0 to 511, 512 to 1023, and
1024 to 65535. Therefore, ports below 1024 have only a
small PAT pool.
If you have a lot of traffic that uses the lower port ranges,
when using a PAT pool, you can now specify a flat range of
ports to be used instead of the three unequal-sized tiers:
either 1024 to 65535, or 1 to 65535.
We modified the following command: nat source dynamic
[pat-pool mapped_object [flat [include-reserve]]].
This feature is not available in 8.5(1) or 8.6(1).
8.4(3) Each PAT IP address allows up to 65535 ports. If 65535
ports do not provide enough translations, you can now
enable extended PAT for a PAT pool. Extended PAT uses
65535 ports per service, as opposed to per IP address, by
including the destination address and port in the translation
information.
We modified the following command: nat source dynamic
[pat-pool mapped_object [extended]].
This feature is not available in 8.5(1) or 8.6(1).
Feature History for Twice NAT
Cisco ASA Series CLI Configuration Guide
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