Nat Cli Commands; Intelligent Nat - 3Com OfficeConnect 3C100XF Cli User's Manual

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HAPTER DDRESS

NAT CLI Commands

add nat static <name>
interface <name>
public_address <ip_
address_range>
private_address <ip_
address_range>
add nat dynamic <name>
interface <name>
public_address <ip_
address_range>
private_address <ip_
address_range>

Intelligent NAT

T C
RANSLATION OMMANDS
Use this command to configure static NAT assignments:
add nat static <name> interface <name> public_address <ip_address_range>
private_address <ip_address_range>
Use this command to configure a NAT public pool:
add nat dynamic <name> interface <name> public_address
<ip_address_range> private_address <ip_address_range>
There are some applications which initiate connections from the client on the local
LAN but also initiate additional connections from the remote host. For example, a
client on the local LAN initiates a Transmission Control Protocol (TCP) connection
to a remote host. The application on the remote host then starts sending User
Datagram Protocol (UDP) frames containing video and audio content.
The address translator dynamically establishes a mapping between the public port
number and the IP address of the local LAN client when the initial TCP connection
was initiated. With this established mapping, all frames from the remote host can
be mapped back to the local LAN client's private address. However, the UDP
connection/stream, initiated from the remote host, does not have an existing port
mapping. When received, the translator does not know for certain which client on
the local LAN the frame should be directed to unless it has knowledge of the
application itself.
The OffiiceConnect Gateway has several features which attempt to make these
applications work. They are Intelligent NAT and the Default Workstation.
Intelligent NAT directs the frame to the local client which currently has other
existing connection(s) with the remote host. If more than one local client has
existing connections, then the client who initiated the most recent session is
chosen. The Default Workstation, if configured, is used when Intelligent NAT
fails to find a local client to direct the frame to. Default Workstation is
configured with the private address of a client on the local LAN. This client address
typically is the workstation that is used for telecommuting or internet gaming.
The OffiiceConnect Gateway can also be configured to enable access to servers on
the local LAN. If only one server is to be accessible, then Default Workstation
can be used.