Nat-Pt Overview - 3Com MSR 50 Series Configuration Manual

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NAT-PT Overview

NAT-PT C
When configuring NAT-PT, go to these sections for information you are interested
in:
"NAT-PT Overview" on page 679
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"Configuring NAT-PT" on page 681
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"Displaying and Maintaining NAT-PT" on page 686
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"NAT-PT Configuration Example" on page 687
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"Troubleshooting NAT-PT" on page 690
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The IPv6 application is a gradual process in which IPv4 networks and IPv6
networks will co-exist to communicate with each other for a long period of time.
The Network Address Translation - Protocol Translation (NAT-PT) realizes translation
between IPv4 and IPv6 addresses, implementing communications between IPv4
and IPv6 networks. For example, it can enable a host in an IPv6 network to access
the FTP server in an IPv4 network.
As shown in Figure 200, NAT-PT runs on the device on the border between IPv4
and IPv6 networks. The NAT-PT process is implemented on the device, which is
transparent to both IPv4 and IPv6 networks. Users between IPv6 networks and
IPv4 networks can communicate, without any change to host configurations of
the existing IPv4 networks.
Figure 200 Network diagram for NAT-PT
IPv 4 host NAT - PT
In view of the following limitations, NAT-PT is not recommended in some
applications (for example, tunneling is recommended in the case where an IPv6
host needs to communicate with another IPv6 host across an IPv4 network).
The request and response packets of a same session must be translated by the
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same NAT-PT device.
The Options field in the IPv4 packet header cannot be translated.
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NAT-PT does not provide end-to-end security.
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Currently, NAT-PT supports ICMP, DNS, FTP, and other protocols that employ the
network layer protocol but have no address information in the protocol messages.
To get more information about NAT-PT, go to these topics:
ONFIGURATION
IPv 6 host