Some client server applications use a multicast packet to send large streams of data to many hosts with a single transmission. The multicast packet uses special addressing at Layer 3 and Layer 2 to communicate with clients that have been configured to receive these packets. The multicast packet contains a Class D IP address to specify the group of devices that are to receive the packet. This group is known as the multicast group, and the IP address translates directly to a multicast Ethernet address. The Ethernet multicast address has the first 24 bits set to 01-00-5E, the next bit is set to 0, and the last 23 bits are set to match the low 23 bits of the IP multicast address. Figure B-6 shows how Layer 3 multicast addresses translate to Layer 2 Ethernet addresses.
Well-known or assigned IP protocols are registered with the IANA. The information presented here is reproduced with permission from the IANA. For the most current IP protocol number assignment information, refer to www.iana.org/numbers.htm under the "Multicast Addresses" link.
Host extensions for IP multicasting (RFC 1112) specifies the extensions required of a host implementation of the Internet Protocol to support multicasting. The multicast addresses are in the range 224.0.0.0 through 239.255.255.255. Current addresses are listed in the table that follows.
The range of addresses between 224.0.0.0 and 224.0.0.255, 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 within this range, regardless of its TTL.
Table B-4 shows the registered multicast addresses, along with the application, and the RFC number (if applicable) or other reference.
Table B-4. Registered Multicast Addresses and Associated Applications, RFCs, and References
Group, Application, and References | Address |
|---|
Base address (reserved) RFC 1112 | 224.0.0.0 |
All systems on this subnet RFC 1112 | 224.0.0.1 |
All routers on this subnet | 224.0.0.2 |
Unassigned | 224.0.0.3 |
DVMRP Routers RFC 1075 | 224.0.0.4 |
OSPFIGP OSPFIGP all routers RFC 2328 | 224.0.0.5 |
OSPFIGP OSPFIGP designated routers RFC 2328 | 224.0.0.6 |
ST Routers RFC 1190 | 224.0.0.7 |
ST Hosts RFC 1190 | 224.0.0.8 |
RIP2 Routers RFC 1723 | 224.0.0.9 |
EIGRP Routers | 224.0.0.10 |
Mobile agents | 224.0.0.11 |
DHCP Server/Relay agent RFC 1884 | 224.0.0.12 |
All PIM routers | 224.0.0.13 |
RSVP-ENCAPSULATION | 224.0.0.14 |
all-cbt-routers | 224.0.0.15 |
designated-sbm | 224.0.0.16 |
all-sbms | 224.0.0.17 |
VRRP | 224.0.0.18 |
IPAllL1Iss | 224.0.0.19 |
IPAllL2Iss | 224.0.0.20 |
IPAllIntermediate Systems | 224.0.0.21 |
IGMP | 224.0.0.22 |
GLOBECAST-ID | 224.0.0.23 |
Unassigned | 224.0.0.24 |
router-to-switch | 224.0.0.25 |
Unassigned | 224.0.0.26 |
Al MPP Hello | 224.0.0.27 |
ETC Control | 224.0.0.28 |
GE-FANUC | 224.0.0.29 |
indigo-vhdp | 224.0.0.30 |
shinbroadband | 224.0.0.31 |
digistar | 224.0.0.32 |
ff-system-management | 224.0.0.33 |
pt2-discover | 224.0.0.34 |
DXCLUSTER | 224.0.0.35 |
DTCP Announcement | 224.0.0.36 |
Zeroconfaddr | 224.0.0.37 to 224.0.0.68 |
Reserved | 224.0.0.69 to 224.0.0.100 |
cisco-nhap | 224.0.0.101 |
HSRP | 224.0.0.102 |
MDAP | 224.0.0.103 |
Unassigned | 224.0.0.104 to 224.0.0.250 |
mDNS | 224.0.0.251 |
Unassigned | 224.0.0.25 to 224.0.0.255 |
VMTP Managers Group RFC 1045 | 224.0.1.0 |
NTP (Network Time Protocol) RFC 1119 | 224.0.1.1 |
SGI-Dogfight | 224.0.1.2 |
Rwhod | 224.0.1.3 |
VNP | 224.0.1.4 |
Artificial Horizons Aviator | 224.0.1.5 |
NSS (Name Service Server) | 224.0.1.6 |
AUDIONEWS (Audio News Multicast) | 224.0.1.7 |
SUN NIS+ Information Service | 224.0.1.8 |
MTP (Multicast Transport Protocol) | 224.0.1.9 |
IETF-1-LOW-AUDIO | 224.0.1.10 |
IETF-1-AUDIO | 224.0.1.11 |
IETF-1-VIDEO | 224.0.1.12 |
IETF-2-LOW-AUDIO | 224.0.1.13 |
IETF-2-AUDIO | 224.0.1.14 |
IETF-2-VIDEO | 224.0.1.15 |
MUSIC-SERVICE | 224.0.1.16 |
SEANET-TELEMETRY | 224.0.1.17 |
SEANET-IMAGE | 224.0.1.18 |
MLOADD | 224.0.1.19 |
Any private experiment | 224.0.1.20 |
DVMRP on MOSPF | 224.0.1.21 |
SVRLOC | 224.0.1.22 |
XINGTV | 224.0.1.23 |
microsoft-ds | 224.0.1.24 |
nbc-pro | 224.0.1.25 |
nbc-pfn | 224.0.1.26 |
lmsc-calren-1 | 224.0.1.27 |
lmsc-calren-2 | 224.0.1.28 |
lmsc-calren-3 | 224.0.1.29 |
lmsc-calren-4 | 224.0.1.30 |
ampr-info | 224.0.1.31 |
Mtrace | 224.0.1.32 |
RSVP-encap-1 | 224.0.1.33 |
RSVP-encap-2 | 224.0.1.34 |
SVRLOC-DA | 224.0.1.35 |
rln-server | 224.0.1.36 |
proshare-mc | 224.0.1.37 |
Dantz | 224.0.1.38 |
cisco-rp-announce | 224.0.1.39 |
cisco-rp-discovery | 224.0.1.40 |
gatekeeper | 224.0.1.41 |
iberiagames | 224.0.1.42 |
nwn-discovery | 224.0.1.43 |
nwn-adaptor | 224.0.1.44 |
isma-1 | 224.0.1.45 |
isma-2 | 224.0.1.46 |
telerate | 224.0.1.47 |
Ciena | 224.0.1.48 |
dcap-servers RFC 2114 | 224.0.1.49 |
dcap-clients RFC 2114 | 224.0.1.50 |
mcntp-directory | 224.0.1.51 |
mbone-vcr-directory | 224.0.1.52 |
Heartbeat | 224.0.1.53 |
sun-mc-grp | 224.0.1.54 |
extended-sys | 224.0.1.55 |
pdrncs | 224.0.1.56 |
tns-adv-multi | 224.0.1.57 |
vcals-dmu | 224.0.1.58 |
Zuba | 224.0.1.59 |
hp-device-disc | 224.0.1.60 |
tms-production | 224.0.1.61 |
Sunscalar | 224.0.1.62 |
mmtp-poll | 224.0.1.63 |
compaq-peer | 224.0.1.64 |
iapp | 224.0.1.65 |
multihasc-com | 224.0.1.66 |
serv-discovery | 224.0.1.67 |
Mdhcpdisover RFC 2730 | 224.0.1.68 |
MMP-bundle-discovery1 | 224.0.1.69 |
MMP-bundle-discovery2 | 224.0.1.70 |
XYPOINT DGPS Data Feed | 224.0.1.71 |
GilatSkySurfer | 224.0.1.72 |
SharesLive | 224.0.1.73 |
NorthernData | 224.0.1.74 |
SIP | 224.0.1.75 |
IAPP | 224.0.1.76 |
AGENTVIEW | 224.0.1.77 |
Tibco Multicast1 | 224.0.1.78 |
Tibco Multicast2 | 224.0.1.79 |
MSP | 224.0.1.80 |
OTT (One-way Trip Time) | 224.0.1.81 |
TRACKTICKER | 224.0.1.82 |
dtn-mc | 224.0.1.83 |
jini-announcement | 224.0.1.84 |
jini-request | 224.0.1.85 |
sde-discovery | 224.0.1.86 |
DirecPC-SI | 224.0.1.87 |
B1Rmonitor | 224.0.1.88 |
3Com-AMP3 dRMON | 224.0.1.89 |
ImFtmSvc | 224.0.1.90 |
NQDS4 | 224.0.1.91 |
NQDS5 | 224.0.1.92 |
NQDS6 | 224.0.1.93 |
NLVL12 | 224.0.1.94 |
NTDS1 | 224.0.1.95 |
NTDS2 | 224.0.1.96 |
NODSA | 224.0.1.97 |
NODSB | 224.0.1.98 |
NODSC | 224.0.1.99 |
NODSD | 224.0.1.100 |
NQDS4R | 224.0.1.101 |
NQDS5R | 224.0.1.102 |
NQDS6R | 224.0.1.103 |
NLVL12R | 224.0.1.104 |
NODS1R | 224.0.1.105 |
NODS2R | 224.0.1.106 |
NODSAR | 224.0.1.107 |
NODSBR | 224.0.1.108 |
NODSCR | 224.0.1.109 |
NODSDR | 224.0.1.110 |
MRM | 224.0.1.111 |
TVE-FILE | 224.0.1.112 |
TVE-ANNOUNCE | 224.0.1.113 |
Mac Srv Loc | 224.0.1.114 |
Simple Multicast | 224.0.1.115 |
SpectraLinkGW | 224.0.1.116 |
Dieboldmcast | 224.0.1.117 |
Tivoli Systems | 224.0.1.118 |
pq-lic-mcast | 224.0.1.119 |
HYPERFEED | 224.0.1.120 |
Pipesplatform | 224.0.1.121 |
LiebDevMgmg-DM | 224.0.1.122 |
TRIBALVOICE | 224.0.1.123 |
Unassigned (Retracted 1/29/01) | 224.0.1.124 |
PolyCom Relay1 | 224.0.1.125 |
Infront Multi1 | 224.0.1.126 |
XRX DEVICE DISC | 224.0.1.127 |
CNN | 224.0.1.128 |
PTP-primary | 224.0.1.129 |
PTP-alternate1 | 224.0.1.130 |
PTP-alternate2 | 224.0.1.131 |
PTP-alternate3 | 224.0.1.132 |
ProCast | 224.0.1.133 |
3Com Discp | 224.0.1.134 |
CS-Multicasting | 224.0.1.135 |
TS-MC-1 | 224.0.1.136 |
Make Source | 224.0.1.137 |
Teleborsa | 224.0.1.138 |
SUMAConfig | 224.0.1.139 |
Unassigned | 224.0.1.140 |
DHCP-SERVERS | 224.0.1.141 |
CN Router-LL | 224.0.1.142 |
EMWIN | 224.0.1.143 |
Alchemy Cluster | 224.0.1.144 |
Satcast One | 224.0.1.145 |
Satcast Two | 224.0.1.146 |
Satcast Three | 224.0.1.147 |
Intline | 224.0.1.148 |
8x8 Multicast | 224.0.1.149 |
Unassigned | 224.0.1.150 |
Intline-1 | 224.0.1.151 |
Intline-2 | 224.0.1.152 |
Intline-3 | 224.0.1.153 |
Intline-4 | 224.0.1.154 |
Intline-5 | 224.0.1.155 |
Intline-6 | 224.0.1.156 |
Intline-7 | 224.0.1.157 |
Intline-8 | 224.0.1.158 |
Intline-9 | 224.0.1.159 |
Intline-10 | 224.0.1.160 |
Intline-11 | 224.0.1.161 |
Intline-12 | 224.0.1.162 |
Intline-13 | 224.0.1.163 |
Intline-14 | 224.0.1.164 |
Intline-15 | 224.0.1.165 |
marratech-cc | 224.0.1.166 |
EMS-InterDev | 224.0.1.167 |
itb301 | 224.0.1.168 |
rtv-audio | 224.0.1.169 |
rtv-video | 224.0.1.170 |
HAVI-Sim | 224.0.1.171 |
Nokia Cluster | 224.0.1.172 |
host-request | 224.0.1.173 |
host-announce | 224.0.1.174 |
ptk-cluster | 224.0.1.175 |
Proxim Protocol | 224.0.1.176 |
Unassigned | 224.0.1.177 to 224.0.0.255 |
"rwho" Group (BSD) (unofficial) | 224.0.2.1 |
SUN RPC PMAPPROC_CALLIT | 224.0.2.2 |
SIAC MDD Service | 224.0.2.64 to 224.0.2.95 |
CoolCast | 224.0.2.96 to 224.0.2.127 |
WOZ-Garage | 224.0.2.128 to 224.0.2.191 |
SIAC MDD Market Service | 224.0.2.192 to 224.0.2.255 |
RFE Generic Service | 224.0.3.0 to 224.0.3.255 |
RFE Individual Conferences | 224.0.4.0 to 224.0.4.255 |
CDPD Groups | 224.0.5.0 to 224.0.5.127 |
SIAC Market Service | 224.0.5.128 to 224.0.5.191 |
Unassigned IANA | 224.0.5.192 to 224.0.5.255 |
Cornell ISIS Project | 224.0.6.0 to 224.0.6.127 |
Unassigned IANA | 224.0.6.128 to 224.0.6.255 |
Where-Are-You | 224.0.7.0 to 224.0.7.255 |
INTV | 224.0.8.0 to 224.0.8.255 |
Invisible Worlds | 224.0.9.0 to 224.0.9.255 |
DLSw Groups | 224.0.10.0 to 224.0.10.255 |
NCC.NET Audio | 224.0.11.0 to 224.0.11.255 |
Microsoft and MSNBC | 224.0.12.0 to 224.0.12.63 |
UUNET PIPEX Net News | 224.0.13.0 to 223.0.13.255 |
NLANR | 224.0.14.0 to 224.0.14.255 |
Hewlett Packard | 224.0.15.0 to 224.0.15.255 |
XingNet | 224.0.16.0 to 224.0.16.255 |
Mercantile & Commodity Exchange | 224.0.17.0 to 224.0.17.31 |
NDQMD1 | 224.0.17.32 to 224.0.17.63 |
ODN-DTV | 224.0.17.64 to 224.0.17.127 |
Dow Jones | 224.0.18.0 to 224.0.18.255 |
Walt Disney Company | 224.0.19.0 to 224.0.19.63 |
Cal Multicast | 224.0.19.64 to 224.0.19.95 |
SIAC Market Service | 224.0.19.96 to 224.0.19.127 |
IIG Multicast | 224.0.19.128 to 224.0.19.191 |
Metropol | 224.0.18.192 to 224.0.19.207 |
Xenoscience, Inc. | 224.0.19.208 to 224.0.19.239 |
HYPERFEED | 224.0.19.240 to 224.0.19.255 |
MS-IP/TV | 224.0.20.0 to 224.0.20.63 |
Reliable Network Solutions | 224.0.20.64 to 224.0.20.127 |
TRACKTICKER Group | 224.0.20.128 to 224.0.20.143 |
CNR Rebroadcast MCA | 224.0.20.144 to 224.0.20.207 |
Talarian MCAST | 224.0.21.0 to 224.0.21.127 |
WORLD MCAST | 224.0.22.0 to 224.0.22.255 |
Domain Scoped Group | 224.0.252.0 to 224.0.252.255 |
Report Group | 224.0.253.0 to 224.0.253.255 |
Query Group | 224.0.254.0 to 224.0.254.255 |
Border Routers | 224.0.255.0 to 224.0.255.255 |
ST Multicast Groups RFC 1190 | 224.1.0.0 to 224.1.255.255 |
Multimedia Conference Calls | 224.2.0.0 to 224.2.127.253 |
SAPv1 Announcements | 224.2.127.254 |
SAPv0 Announcements (deprecated) | 224.2.127.255 |
SAP Dynamic Assignments | 224.2.128.0 to 224.2.255.255 |
DIS transient groups | 224.252.0.0 to 224.255.255.255 |
MALLOC (temp - renew 1/01) | 225.0.0.0 to 225.255.255.255 |
VMTP transient groups | 232.0.0.0 to 232.255.255.255 |
Static Allocations (temp - renew 03/02) | 233.0.0.0 to 233.255.255.255 |
Administratively Scoped IANA RFC 2365 | 239.0.0.0 to 239.255.255.255 |
Reserved IANA | 239.0.0.0 to 239.63.255.255 |
Reserved IANA | 239.64.0.0 to 239.127.255.255 |
Reserved IANA | 239.128.0.0 to 239.191.255.255 |
Organization-Local Scope RFC 2365 | 239.192.0.0 to 239.251.255.255 |
Site-Local Scope (reserved) RFC 2365 | 239.252.0.0 to 239.252.255.255 |
Site-Local Scope (reserved) RFC 2365 | 239.253.0.0 to 239.253.255.255 |
Site-Local Scope (reserved) RFC 2365 | 239.254.0.0 to 239.254.255.255 |
Site-Local Scope RFC 2365 | 239.255.0.0 to 239.255.255.255 |
rasadv | 239.255.2.2 |
