IGMP Message Structure
Hosts and routers use IGMP to maintain local subnet host group membership and it is required for hosts that support Level 2 IP multicasting. IGMP messages are sent as IP datagrams with the IP Protocol field set to 2. The resulting IP datagram is then encapsulated with the appropriate Network Interface Layer header and trailer. Figure 7-2 shows the resulting frame.
Figure 7-2. IGMP message structure showing the IP header and Network Interface Layer header and trailer
In the IP header of IGMP messages, the Source IP Address field is set to the router or host interface that sent the IGMP message and the Destination IP Address field ...
Get Windows Server® 2008 TCP/IP Protocols and Services now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
