H3C Technologies H3C SecPath F1000-E - Manual (Page 73)

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Configuring AFT
This chapter describes how to configure Address Family Translation (AFT).
NOTE:
AFT configuration is available only at the CLI.
Overview
Application scenario
AFT is a transition technology for communication between IPv4 and IPv6 networks.
As
Figure 56 shows, the AFT router performs address and protocol translation between IPv4 and IPv6
networks. With AFT, IPv6 and IPv4 hosts can communicate with one another without changing their
configurations.
Figure 56 AFT diagram
Basic concepts
DNS64 prefix
A DNS64 prefix is an IPv6 address prefix used to translate IPv4 addresses into IPv6 addresses. The
length of a DNS64 prefix can be 32, 40, 48, 56, 64, or 96 bits, as shown in Figure 57 . The address
translation methods vary depending on the length of the DNS64 prefix. If the length of the DNS64 prefix
is 40, 48, or 56 bits, the IPv4 address has two parts separated by the bits from bit 64 to bit 71.