Cisco Systems 2.5 Scenario 4

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Cisco Router and Security Device Manager 2.5 User’s Guide
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Result
The source address 10.12.12.3 is translated to the address 172.17.4.8 in packets
leaving the router. The port number in the Redirect port field is changed from 137
to 139. Return traffic carrying the destination address 172.17.4.8 is routed to po rt
number 137 of the host with the IP address 10.12.12.3.
You need to create a separate entry for each host/port mapping that you want to
create. You can use the same “Translated to” IP address in each entry, but you
must enter a different “Translated from” IP address in each entry, and a different
set of port numbers.
Scenario 4
You want source-"Translate from"-addresses to use the IP address that is assigned
to the router's Fast Ethernet 0/1 interface 172.17.4.8. You also want to use the
same global IP address for several hosts on the trusted network. Inbound traffic
will contain a different port number based on the destination host. The following
table shows how the fields in the Add Address Translation Rule window would be
used:
Result
The source address 10.12.12.3 is translated to the address 172.17.4.8 in packets
leaving the router. The port number in the Redirect port field is changed from 137
to 139. Return traffic carrying the destination address 172.17.4.8 & port 139 is
routed to port number 137 of the host with the IP add ress 10.12.12.3.
Static/Dynamic
Translate from... fields Translate to... fields
IP Address Net Mask IP Address Redirect Port
Static 10.12.12.3 Leave blank FastEthernet 0/1 UDP
Original Port 137
Translated Port 139