Planet GS-5220 Series User Manual page 255

User's Manual of GS-5220 LCD Series
Figure 4-8-3: 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
Checksum
Type Response Time
Group Address (all zeros if this is a query)
255