This page contains all the Multicast IP Addresses and shows what protocol they are mapped to. Should you ever use a packet sniffer to try and see what's on the network and you capture a packet with a destination IP Address of 224.X.X.X, then simply look up this list and you will know what the purpose of that packet was :)
Internet Multicast Addressess
Host Extensions for IP Multicasting [RFC1112] specifies the extensions required of a host implementation of the Internet Protocol (IP) to support multicasting. Current addresses are listed below.
The range of addresses between 184.108.40.206 and 220.127.116.11, inclusive, is reserved for the use of routing protocols and other low-level topology discovery or maintenance protocols, such as gateway discovery and group membership reporting. Multicast routers should not forward
any multicast datagram with destination addresses in this range, regardless of its TTL.
18.104.22.168 Base Address (Reserved) [RFC1112,JBP]
22.214.171.124 All Systems on this Subnet [RFC1112,JBP]
126.96.36.199 All Routers on this Subnet [JBP]
188.8.131.52 Unassigned [JBP]
184.108.40.206 DVMRP Routers [RFC1075,JBP]
220.127.116.11 OSPFIGP OSPFIGP All Routers [RFC1583,JXM1]
18.104.22.168 OSPFIGP OSPFIGP Designated Routers [RFC1583,JXM1]
22.214.171.124 ST Routers [RFC1190,KS14]
126.96.36.199 ST Hosts [RFC1190,KS14]
188.8.131.52 RIP2 Routers [RFC1723,GSM11]
184.108.40.206 IGRP Routers [Dino Farinacci]
220.127.116.11 Mobile-Agents [Bill Simpson]
18.104.22.168 DHCP Server / Relay Agent [RFC1884]
22.214.171.124 - 126.96.36.199 Unassigned [JBP]
188.8.131.52 "rwho" Group (BSD) (unofficial) [JBP]
184.108.40.206 SUN RPC PMAPPROC_CALLIT [BXE1]
224.0.3.000-220.127.116.11 RFE Generic Service [DXS3]
224.0.4.000-18.104.22.168 RFE Individual Conferences [DXS3]
224.0.5.000-22.214.171.124 CDPD Groups [Bob Brenner]
126.96.36.199-188.8.131.52 Unassigned [IANA]
224.0.6.000-184.108.40.206 Cornell ISIS Project [Tim Clark]
220.127.116.11-18.104.22.168 Unassigned [IANA]
224.0.7.000-22.214.171.124 Where-Are-You [Simpson]
224.0.8.000-126.96.36.199 INTV [Tynan]
224.0.9.000-188.8.131.52 Internet Railroad [Malamud]
184.108.40.206-220.127.116.11 ST Multicast Groups [RFC1190,KS14]
18.104.22.168-22.214.171.124 Multimedia Conference Calls [SC3]
126.96.36.199-188.8.131.52 DIS transient groups [Joel Snyder]
184.108.40.206-220.127.116.11 VMTP transient groups [RFC1045,DRC3]
These addresses are listed in the Domain Name Service under MCAST.NET
Note that when used on an Ethernet or IEEE 802 network, the 23
low-order bits of the IP Multicast address are placed in the low-order
23 bits of the Ethernet or IEEE 802 net multicast address
18.104.22.168.0.0. See the section on "IANA ETHERNET ADDRESS BLOCK".
[RFC1045] Cheriton, D., "VMTP: Versatile Message Transaction
Protocol Specification", RFC 1045, Stanford University,
[RFC1075] Waitzman, D., C. Partridge, and S. Deering "Distance Vector
Multicast Routing Protocol", RFC-1075, BBN STC, Stanford
University, November 1988.
[RFC1112] Deering, S., "Host Extensions for IP Multicasting",
STD 5, RFC 1112, Stanford University, August 1989.
[RFC1119] Mills, D., "Network Time Protocol (Version 1), Specification
and Implementation", STD 12, RFC 1119, University of
Delaware, July 1988.
[RFC1190] Topolcic, C., Editor, "Experimental Internet Stream
Protocol, Version 2 (ST-II)", RFC 1190, CIP Working Group,
[RFC1583] Moy, J., "The OSPF Specification", RFC 1583, Proteon,
[RFC1723] Malkin, G., "RIP Version 2: Carying Additional Information",
RFC 1723, Xylogics, November 1994.
[RFC1884] Hinden, R., and S. Deering, "IP Version 6 Addressing
Architecture", RFC 1884, Ipsilon Networks, Xerox PARC,