TCP/IP Tutorial and Technical Overview - IBM Redbooks

information. However, plug-and-play configuration is possible in both small and
large networks without the requirement for DHCP servers.
The stateless address configuration process, together with the fact that more
than one address can be allocated to the same interface, also allows for the
graceful renumbering of all the nodes on a site (for example, if a switch to a new
network provider necessitates new addressing) without disruption to the network.
For further details, refer to RFC 2462.
9.3.2 Multicast Listener Discovery (MLD)
The process used by a router to discover the members of a particular multicast
group is known as Multicast Listener Discovery (MLD). MLD is a subset of
ICMPv6 and provides the equivalent function of IGMP for IPv4 (see 3.3, “Internet
Group Management Protocol (IGMP)” on page 119). This information is then
provided by the router to whichever multicast routing protocol is being used so
that multicast packets are correctly delivered to all links where there are nodes
listening for the appropriate multicast address.
MLD is specified in RFC 2710 – Multicast Listener Discovery (MLD) for IPv6.
MLD uses ICMPv6 messages of the format shown in Figure 9-22.
Vers.
Traffic Class
Figure 9-22 MLD message format
Payload Length Next = 58 Hops = 1
(Link Local)Source Address
Destination Address
Type Code = 0 Checksum
Max. Response Delay
IP Multicast Address
Flow Label
Reserved
Chapter 9. IP version 6 365