Interlogix NS4702-24P-4S-4X User Manual page 165

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
Type
The IGMP Type codes are shown below:
Type
0x11
0x11
Figure 4-8-3: IGMP Snooping Multicast Stream Control
16
Response Time
Group Address (all zeros if this is a query)
Meaning
Membership Query (if Group Address is 0.0.0.0)
Specific Group Membership Query (if Group Address is
Checksum
165
31