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Chapter 4: Web configuration
NS3562-8P-2S User Manual
115
IGMP snooping multicast stream control
IGMP versions 1 and 2
Multicast groups allow members to join or leave at any time. IGMP provides the method
for members and multicast routers to communicate when joining or leaving a multicast
group. IGMP version 1 is defined in RFC 1112. It has a fixed packet size and no
optional data. The format of an IGMP packet is shown below:
IGMP message format
Octets:
0
8
16
31
Type
Response Time
Checksum
Group Address (all zeros if this is a query)