Alcatel-Lucent OmniSwitch 10K - Page 103

OmniSwitch OS6860/OS6900/OS10K Troubleshooting Guide Part No.032996-00 Rev.A
AOS Release 7.X and 8.X January 2015
Alcatel-Lucent Page 103 of 148
6. Description of the Protocol for Multicast Routers The information gathered by IGMP is provided to
whichever multicast routing protocol is being used by the router, in order to ensure that multicast packets are
delivered to all networks where there are interested receivers.
In AOS each multicast router becomes a "dynamic neighbor" by default. AOS switches replicate all multicast
packets and all IGMP messages to all neighbors due to compliance with RFC 3376.
IPMVLAN scenarios in Ethernet-Services mode
Not supported in AOS 7 and AOS 8
Example of IGMP version 2 messages
IGMP Membership Report
Note:
All IGMP messages need to have TTL field set to 1. Messages with other values are dropped.
In IGMP version 2 a group address which is registered by IGMP Membership Report corresponds to a
destination IP address of a packet.
MAC: ------ MAC Header ------
MAC:
MAC: Destination Address : 01 00 5E 01 01 01
MAC: Source Address : 00 00 00 08 73 F0
MAC: Type : 0x0800 (Ethernet II)
MAC:
IP: ------ IP Header -----------
IP:
IP: Version = 04 (0x04)
IP: Header Length = 20 (0x14)
IP: Differentiated Services Field = 0 (0x00)
IP: Type of Service = 00 (0x00)
IP: Total Length = 28 (0x001C)
IP: Identification = 0 (0x0000)
IP: Fragment Offset = 0
IP: Time to Live = 1 (0x01)
IP: Protocol = IGMP
IP: Checksum = 0x…
IP: Source Address = 10.0.0.111
IP: Destination Address = 239.1.1.1
IP:
IGMP: ------ IGMP Header -----------
IGMP:
IGMP: Version = 2 (0x2)
IGMP: Type = Membership Report v2 (0x16)
IGMP: Max Response Time = 100 (0x64)
IGMP: Checksum = 0xF796
IGMP: Group = 239.1.1.1
IGMP:
IGMP Leave
Note:
In IGMP version 2 a leave message is always sent with 224.0.0.2 IP destination address.
MAC: ------ MAC Header ------
MAC:
MAC: Destination Address : 01 00 5E 00 00 02
MAC: Source Address : 00 00 00 08 73 F0
MAC: Type : 0x0800 (Ethernet II)
MAC:
IP: ------ IP Header -----------
IP:
IP: Version = 04 (0x04)
IP: Header Length = 20 (0x14)
IP: Differentiated Services Field = 0 (0x00)
IP: Type of Service = 00 (0x00)
IP: Total Length = 28 (0x001C)
IP: Identification = 0 (0x0000)
IP: Fragment Offset = 0