Configuration using Web Based Management and Command Line Interface
4.5 The Switch menu
SCALANCE X-300 / X-400
Configuration Manual, 10/2014, C79000-G8976-C187-22
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Command
Description
Comment
loopdp <port>
[B | F | S]
Defines the behavior of a port for loop detection:
•
"Blocked"
•
"Forwarder"
•
"Sender"
Administrator only.
rxthres <port>
<count>
Specifies the Rx.Threshold.
Administrator only.
local <port> [N |
D]
Specifies the reaction to a local loop.
Administrator only.
remote <port>
[N | D]
Specifies the reaction to a remote loop.
Administrator only.
reset <port>
Reactivates the port if it was deactivated due to a detected
loop.
Administrator only.
4.5.25
NAT - Network Address Translation
Note
The NAT function is available only with SCALANCE X300 and SCALANCE X408.
Network Address Translation (NAT) means the translation of a network address in a router
related to a data stream. This does not necessarily only mean the IP address. If nodes with
local addresses take over server functions for the outside, not only the IP addresses but also
the port numbers will be replaced in the router.
The most common reason for the use of NAT is that the IP addresses of the devices in the
local network should not be visible to the outside.
Traditional NAT
With Traditional NAT, connections are only permitted in one direction, originating from the
local network. Traditional NAT distinguishes between the methods Basic NAT and NAPT
(Network Address Port Translation).
In Basic NAT, a pool of global/external addresses is kept available for the translation and
each internal address is converted to an external address.
With NAPT, the transport identifiers, for example port numbers, are included in the
translation. For this reason, this method only requires a single external address for
translation.
1:1 NAT with SCALANCE X300/X400
A special variant of NAT that is used with SCALANCE X300/X400 is 1:1 NAT, also known as
bidirectional NAT. This variant allows connection establishment in both directions; in other
words, also originating from the external network into the local network. The translation of
the network addresses is performed using a static table. In this table, you specify 1:1 the
global IP address into which a local IP address will be translated and vice versa.