What is IGMP join?
When an IGMP client connected to a switch port needs to receive multicast traffic from a specific group, it joins the group by sending an IGMP report (join request) to the network. (The multicast group specified in the join request is determined by the requesting application running on the IGMP client.)
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What is the destination of the IGMP messages?
IGMP Membership Report messages : IGMP Membership Report messages are sent by multicast clients inside the subnet to the router to inform the intention to join a multicast group or in response to a Membership Query (MQ) message sent by the router.
What is IP IGMP Join Group?
“ip igmp join-group” causes the router to send an IGMP membership report on the interface where it is configured. The mcast packets will therefore be received and process switched by the router. This command is usually used for test purposes.
What is the size of the following fields with respect to IGMP?
The fields in the IGMPv1 header are defined as follows: VersionA 4-bit field set to 1 to indicate IGMPv1. TypeA 4-bit field that indicates the type of IGMP message….IGMP Version 1 (IGMPv1)
| Host Membership Report | Host Membership Query | |
|---|---|---|
| Destination IP Address (IP header) | Group IP Address | 224.0.0.1 |
How does a device join a multicast group?
A device can join a group by sending an IGMP “membership report” message to the group IP address. This packet is received by a multicast router on the segment, and the router does whatever is necessary to start forwarding the data stream to this device.
How do I join a multicast group?
To join a multicast group, a host sends a join message, using the Internet Group Management Protocol (IGMP), to its first-hop router. Groups are identified by a single class D IP address (in the range 224.0. 0.0 to 239.255. 255.255).
How does IGMP multicast work?
When PIM is the multicast protocol in use, IGMP begins the process as follows: To join a multicast group, G, a host conveys its membership information through IGMP. The routing device then forwards data packets addressed to a multicast group G to only those interfaces on which explicit join messages have been received.
What is the IP address of the IGMP group membership report?
IGMP group membership reports are destined to the group IP address for which the device is reporting. IGMPv2 leave-group messages are destined to the address 224.0.0.2 (all devices on a subnet). IGMPv3 membership reports are destined to the address 224.0.0.22; all IGMPv3-capable multicast devices must listen to this address.
How are IGMP packets transmitted using multicast group addresses?
IGMP packets are transmitted using IP multicast group addresses as follows: IGMP general queries are destined to the address 224.0.0.1 (all systems on a subnet). IGMP group-specific queries are destined to the group IP address for which the device is querying.
Where are IGMP group-specific queries and IGMPv2 leave-group messages destined to?
IGMP group-specific queries are destined to the group IP address for which the device is querying. IGMP group membership reports are destined to the group IP address for which the device is reporting. IGMPv2 leave-group messages are destined to the address 224.0.0.2 (all devices on a subnet).
What is the IGMP join process for hosts?
When a host wants to join a multicast group, the host sends one or more unsolicited membership reports for the multicast group it wants to join. The IGMP join process is the same for IGMPv1 and IGMPv2 hosts. In IGMPv3, the join process for hosts proceeds as follows:
