Allied Telesis OmniConnect ISDN - Manual (Page 59)

OmniConnect / ISDN User’s Manual Page 53
Part number 613-10787-00
6.3.6. OmniNAT setup
The OmniNAT Setup screen allows control of the Network Address Translation (NAT)
parameters. The OmniNAT feature of the OmniConnect access device allows the connection
of multiple users to an ISP using a single user ISP account. OmniNAT performs all the IP
address translation for all the incoming and outgoing TCP/IP packets based on either the IP
address or the TCP or UDP port number. OmniNAT uses the global IP address assigned by
the ISP as the source address of all the outgoing packets. For all incoming packets, OmniNAT
performs the reverse operation by replacing the global IP address with the locally assigned
client IP address. OmniNAT may be enabled or disabled by checking the Enable OmniNAT
or Disable OmniNAT check boxes.
If OmniNAT is enabled, there still may be a requirement to further configure either the IP
addresses for static NAT entries or Port Address Translation features. To configure static
NAT entries, press the Configure Static NAT button. To configure Port Address Translation,
press the Configure Static PAT button.
6.3.7. Static NAT entries
The Static NAT Entries screen allows control of the local-to-global IP address Network
Address Translation (NAT) parameters. Using this screen, users have the ability to translate
internal, private addresses (such as 192.168.1.5) to globally unique, externally visible IP
addresses. This powerful feature allows users to take advantage of security and cost-
effectiveness of NAT for the bulk of their client PCs but still allow external users to access
internal resources, such as a web server or e-mail server.
In order to allow internal resources to be accessed by the WAN, assign a local IP address (for
example, the web server, a globally unique IP address. Up to 4 such address pairs may be
assigned. Entries must be as shown in the example above. In this case, all packets originating