Internet Group Management Protocol (IGMP)

IGMP is used by IP hosts to manage their dynamic multicast group membership. It is also used by connected routers to discover these group members.

History

RFC 988 - IGMP version 0

RFC 1054 - IGMP version 1

RFC 2236 - IGMP version 2

Protocol dependencies

Example traffic

(Certain addresses munged)

No.     Time        Source                Destination           Protocol Info
     38 18.419525   192.168.xxx.xxx        239.255.255.250       IGMP     V2 Membership Report

Frame 38 (46 bytes on wire, 46 bytes captured)
    Arrival Time: May 29, 2005 16:45:58.272406000
    Time delta from previous packet: 0.481171000 seconds
    Time since reference or first frame: 18.419525000 seconds
    Frame Number: 38
    Packet Length: 46 bytes
    Capture Length: 46 bytes
    Protocols in frame: eth:ip:igmp
Ethernet II, Src: xx:xx:xx:xx:xx:xx, Dst: 01:00:5e:7f:ff:fa
    Destination: 01:00:5e:7f:ff:fa (01:00:5e:7f:ff:fa)
    Source: xx:xx:xx:xx:xx:00 (ABCD:xx:00)
    Type: IP (0x0800)
Internet Protocol, Src Addr: 192.168.xxx.xxx (192.168.xxx.xxx), Dst Addr: 239.255.255.250 (239.255.255.250)
    Version: 4
    Header length: 24 bytes
    Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00)
        0000 00.. = Differentiated Services Codepoint: Default (0x00)
        .... ..0. = ECN-Capable Transport (ECT): 0
        .... ...0 = ECN-CE: 0
    Total Length: 32
    Identification: 0x58dd (22749)
    Flags: 0x00
        0... = Reserved bit: Not set
        .0.. = Don't fragment: Not set
        ..0. = More fragments: Not set
    Fragment offset: 0
    Time to live: 1
    Protocol: IGMP (0x02)
    Header checksum: 0x10f4 (correct)
    Source: 192.168.xxx.xxx (192.168.xxx.xxx)
    Destination: 239.255.255.250 (239.255.255.250)
    Options: (4 bytes)
        Router Alert: Every router examines packet
Internet Group Management Protocol
    IGMP Version: 2
    Type: Membership Report (0x16)
    Max Response Time: 0,0 sec (0x00)
    Header checksum: 0xfa04 (correct)
    Multicast Address: 239.255.255.250 (239.255.255.250)

0000  01 00 5e 7f ff fa xx xx xx xx xx xx 08 00 46 00   ..^.....Z#.s..F.
0010  00 20 58 dd 00 00 01 02 10 f4 c0 a8 xx xx ef ff   . X..........d..
0020  ff fa 94 04 00 00 16 00 fa 04 ef ff ff fa         ..............

Wireshark

The IGMP dissector is (fully functional, partially functional, not existing, ... whatever the current state is). Also add info of additional Wireshark features where appropriate, like special statistics of this protocol.

Preference Settings

There are no IGMP specific preference settings.

Example capture file

SampleCaptures/IGMP dataset.pcap Sample IGMP version 2.

Display Filter

A complete list of IGMP display filter fields can be found in the display filter reference

Capture Filter

Discussion

IGMP (last edited 2011-06-27 05:08:16 by WenchaoWang)