Juniper IP SERVICES - CONFIGURATION GUIDE V 11.1.X, Configuration Manual

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NAT enables you to translate IP addresses between two address realms (for example,
between an intranet network that uses private, not publicly routable addresses and
the Internet, or between two overlapping, private networks). When incoming traffic
is received, the IP addresses are translated back for delivery within the private
network.
Using NAT at the edge of your intranet provides the following advantages:
■
Allows unregistered private addresses to connect to the Internet by translating
those addresses into globally registered IP addresses
■
Increases network privacy by hiding internal IP addresses from external networks
Platform Considerations
For information about modules that support NAT on ERX14xx models, ERX7xx
models, and the ERX310 Broadband Services Router:
■
See ERX Module Guide, Table 1, Module Combinations for detailed module
specifications.
■
See ERX Module Guide, Appendix A, Module Protocol Support for information about
the modules that support NAT.
NOTE: The E120 and E320 Broadband Services Routers do not support configuration
of NAT.
Module Requirements
To configure NAT on ERX7xx models, ERX14xx models, and the ERX310 router,
you must install a Service Module (SM). For information about installing modules in
E Series Broadband Services Routers, see the
ERX Hardware Guide .
Unlike other line modules, SMs do not pair with corresponding I/O modules that
contain ingress and egress ports. Instead, they receive data from and transmit data
to other line modules with access to ingress and egress ports on their own associated
I/O modules.
For a list of the modules that support NAT, see ERX Module Guide, Appendix A, Module
Protocol Support .
References
For more information about NAT, consult the following resources:
■
RFC 2663-IP Network Address Translator (NAT) Terminology and Considerations
(August 1999)
■
RFC 2694-DNS extensions to Network Address Translators (DNS_ALG) (September
1999)
64 ■
Platform Considerations
JUNOSe 11.1.x IP Services Configuration Guide