HP VPN Firewall Appliances NAT and ALG Configuration Guide

34
Configuring NAT-PT
NAT-PT can be configured only at the CLI.
NAT-PT is not supported on VLAN interfaces and does not support VPN instances, IPv4 fragments, or
ICMPv6 fragments.
Overview
Because of the coexistence of IPv4 networks and IPv6 networks, Network Address Translation–Protocol
Translation (NAT-PT) was introduced to realize translation between IPv4 and IPv6 addresses. For
example, it can enable a host in an IPv6 network to access the FTP server in an IPv4 network.
As shown in Figure 30, N
AT-PT r
uns on the device between IPv4 and IPv6 networks. The address
translation is transparent to both IPv4 and IPv6 networks. Users in the IPv6 and IPv4 networks can
communicate without changing their configurations.
Figure 30 Network diagram
Basic concepts
NAT-PT mechanism
There are three NAT-PT mechanisms to realize translation between IPv4 and IPv6 addresses: static
mapping, dynamic mapping, and NAPT-PT:
• Static mapping
Static mappings are manually configured for translation between IPv6 and IPv4 addresses.
• Dynamic mapping
Dynamic mappings are dynamically generated for translation between IPv6 and IPv4 addresses.
Different from static mappings, dynamic mappings are not fixed one-to-one mappings between
IPv6 and IPv4 addresses.