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
- IP: Typically, IGMP uses IP as its transport protocol. The well known IP protocol type for IGMP traffic is 0x02.
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
Show only the IGMP based traffic:
igmp
Capture Filter
Capture only the IGMP based traffic:
igmp
External links
-
RFC 988 Host Extensions for IP Multicasting - describes the obsolete "version 0" of IGMP
-
RFC 1112 Host Extensions for IP Multicasting - describes version 1 of IGMP
-
RFC 2236 Internet Group Management Protocol, Version 2
-
RFC 3376 Internet Group Management Protocol, Version 3
Discussion
Imported from https://wiki.wireshark.org/IGMP on 2020-08-11 23:15:04 UTC