D-Link DGS-6600-48TS Configuration Guide - Page 511

Prefix Delegation,

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Volume 9-Network Application / Chapter 51-DHCPv6 Client Configuration Chapter Overview Prefix Delegation The Prefix Delegation options provide a mechanism for automated delegation of IPv6 prefixes using DHCPv6. The prefix delegation mechanism is intended for delegating a long-lived prefix from a delegating router (DHCPv6 server) to a requesting router (DHCPv6 client), across an administrative boundary, where the delegating router does not require knowledge about the topology of the links in the network to which the prefixes will be assigned. A delegating router is provides IPv6 prefixes to be delegated to requesting routers. The delegating router chooses a prefixes for delegation, and responds with prefixes which are sent to the requesting router. The requesting router is then responsible for the delegated prefixes. For example, the requesting router might assign a subnet from a delegated prefix to one of its interfaces, and begin sending router advertisements for the prefix on the link. Each prefix has an associated valid and preferred lifetime, which constitutes an agreement about the length of time over which the requesting router is allowed to use the prefix. A requesting router can request an extension of the lifetimes on a delegated prefix and is required to terminate the use of a delegated prefix if the valid lifetime of the prefix expires. The following diagram shows a network architecture in which prefix delegation could be used. Figure 51-2 When a routers subnet requests a delegated prefix, it must assign additional bits to the prefix to generate unique; longer prefixes. For example, if the delegating router in the figure delegates 3FFE:FFFF:0::/48, it might generate 3FFE:FFFF:0:1::/64, 3FFE:FFFF:0:2/64 ..., 3FFE:FFFF:0:N/64 for assignment to links in the other interfaces. If the delegating router assigns a delegated prefix to a link to which the router is attached, and begins to send router advertisements for the prefix on the link, the requesting router must set the valid lifetime in those advertisements to be no later than the valid lifetime specified in the IA_PD Prefix option. A requesting router may use the preferred lifetime specified in the IA_PD Prefix option. DGS-6600 Configuration Guide 511

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Volume 9-Network Application / Chapter 51-DHCPv6 Client Configuration
Chapter Overview
DGS-6600 Configuration Guide
511
Prefix Delegation
The Prefix Delegation options provide a mechanism for automated delegation of IPv6 prefixes using
DHCPv6. The prefix delegation mechanism is intended for delegating a long-lived prefix from a
delegating router (DHCPv6 server) to a requesting router (DHCPv6 client), across an administrative
boundary, where the delegating router does not require knowledge about the topology of the links in
the network to which the prefixes will be assigned.
A delegating router is provides IPv6 prefixes to be delegated to requesting routers. The delegating
router chooses a prefixes for delegation, and responds with prefixes which are sent to the
requesting router. The requesting router is then responsible for the delegated prefixes. For example,
the requesting router might assign a subnet from a delegated prefix to one of its interfaces, and
begin sending router advertisements for the prefix on the link.
Each prefix has an associated valid and preferred lifetime, which constitutes an agreement about
the length of time over which the requesting router is allowed to use the prefix. A requesting router
can request an extension of the lifetimes on a delegated prefix and is required to terminate the use
of a delegated prefix if the valid lifetime of the prefix expires.
The following diagram shows a network architecture in which prefix delegation could be used.
Figure 51-2
When a routers subnet requests a delegated prefix, it must assign additional bits to the prefix to
generate unique; longer prefixes. For example, if the delegating router in the figure delegates
3FFE:FFFF:0::/48, it might generate 3FFE:FFFF:0:1::/64, 3FFE:FFFF:0:2/64 …, 3FFE:FFFF:0:N/64
for assignment to links in the other interfaces. If the delegating router assigns a delegated prefix to a
link to which the router is attached, and begins to send router advertisements for the prefix on the
link, the requesting router must set the valid lifetime in those advertisements to be no later than the
valid lifetime specified in the IA_PD Prefix option. A requesting router may use the preferred lifetime
specified in the IA_PD Prefix option.