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DHCPv6 Configuration
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32. DHCPv6 Configuration
32.1
Introduction to DHCPv6
DHCPv6 [RFC3315] is the IPv6 version for Dynamic Host Configuration Protocol
(DHCP). It is a protocol that assigns IPv6 address as well as other network configuration
parameters such as DNS address, and domain name to DHCPv6 client, DHCPv6 is a
conditional auto address configuration protocol relative to IPv6. In the conditional address
configuration process, DHCPv6 server assigns a complete IPv6 address to client, and
provides DNS address, domain name and other configuration information, maybe the
DHCPv6 packet can transmit through relay delegation, at last the binding of IPv6 address
and client can be recorded by DHCPv6 server, all that can enhance the management of
network; DHCPv6 server can also provide non state DHCPv6 service, that is only assigns
DNS address and domain name and other configuration information but not assigns IPv6
address, it can solve the bug of IPv6 auto address configuration in non state; DHCPv6 can
provide extend function of DHCPv6 prefix delegation, upstream route can assign address
prefix to downstream route automatically, that achieve the IPv6 address auto assignment
in levels of network environment, and resolved the problem of ISP and IPv6 network
dispose.
There are three entities in the DHCPv6 protocol
– the client, the relay and the server.
The DHCPv6 protocol is based on the UDP protocol. The DHCPv6 client sends request
messages to the DHCP server or DHCP relay with the destination port as 547, and the
DHCPv6 server and relay send replying messages with the destination port as 546. The
DHCPv6 client sends solicit or request messages with the multicast address
– ff02::1:2 for
DHCP relay and server.
Fig 32-1 DHCPv6 negotiation
When a DHCPv6 client tries to request an IPv6 address and other configurations from
the DHCPv6 server, the client has to find the location of the DHCP server, and then
DHCPv6 CLIENT
DHCPv6 SERVER
Solicit (Muticast)
Advertise (Unicast)
Request (Muticast)
Reply (Unicast)