QTECH QSW-8300 Инструкция по настройке - Manual (Page 285)

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switch protocol might operate abnormally).
29.5.4 IPv6 DCSCM Troubleshooting
IPv6 DCSCM module acts like ACL, so most problems are caused by improper configuration.
Please read the instructions above carefully.
29.6 MLD
29.6.1 Introduction to MLD
MLD (Multicast Listener Discovery) is the multicast group member (receiver) discovery
protocol serving IPv6 multicast. It is similar to IGMP Protocol in IPv4 multicast application.
Correspondingly, MLD Protocol version1 is similar to IGMP Protocol version2, and MLD
Protocol version2 is similar to IGMP Protocol version3. Current firmware supports MLDv1/
MLDv2.
The IPv6 multicast hosts can join or leave from multicast group at any location, any time,
regardless of the total number of group members. It is unnecessary and impossible for
multicast switch to store the relationship among all host members. Multicast switch simply
finds out via MLD protocol if there are receivers of certain multicast group on the network
segment connected to each port. The only thing host need to do is to keep the record of which
multicast groups it joined.
MLD is unsymmetrical between host and switch: the host needs to respond the MLD query
message of multicast switch with membership report message; the switch periodically sends
membership query message and determines if there is host joining a specific group in its
subnetworks according to the response message received, and after it receives the report of a
host quitting from the group, it sends out the query for the group to confirm if there is no
member left in it.
There are three types of protocol messages of MLD Protocol, that is, Query, Report and Done
(which is corresponding to Leave of IGMPv2). Like IGMPV2, the Query messages include
General Query and Specific Group Query. General Query uses the multicast address FF02::1
of hosts as destination address, the group address is 0; and Specific Group Query use its
group address as destination address. The multicast addresses of MLD use 130, 131 and 132
as data types denoting the three kinds of messages mentioned above. Other logic is basically
same as IGMPv2.
MLD protocol version2 use FF02::16 as destination address of membership report, and 143 as
data type. The other logic of MLD Protocol version2 is similar to IGMP Protocol version3.
29.6.2 MLD Configuration Task List
Start MLD (Required)