While we're on the topic of broadcast... [pinging 224.0.0.1 only produced a list of SGI and Cisco systems. Others may have implemented this since the last time I looked, but I doubt it.] RFC1700: ... > INTERNET MULTICAST ADDRESSES > > 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. > > 224.0.0.0 Base Address (Reserved) [RFC1112,JBP] > 224.0.0.1 All Systems on this Subnet [RFC1112,JBP] > 224.0.0.2 All Routers on this Subnet [JBP] > 224.0.0.3 Unassigned [JBP] > 224.0.0.4 DVMRP Routers [RFC1075,JBP] > 224.0.0.5 OSPFIGP OSPFIGP All Routers [RFC1583,JXM1] > 224.0.0.6 OSPFIGP OSPFIGP Designated Routers [RFC1583,JXM1] > 224.0.0.7 ST Routers [RFC1190,KS14] > 224.0.0.8 ST Hosts [RFC1190,KS14] > 224.0.0.9 RIP2 Routers [GSM11] > 224.0.0.10 IGRP Routers [Dino Farinacci] > 224.0.0.11 Mobile-Agents [Bill Simpson] > 224.0.0.12-224.0.0.255 Unassigned [JBP] > > 224.0.1.0 VMTP Managers Group [RFC1045,DRC3] > 224.0.1.1 NTP Network Time Protocol [RFC1119,DLM1] > 224.0.1.2 SGI-Dogfight [AXC] > 224.0.1.3 Rwhod [SXD] > 224.0.1.4 VNP [DRC3] > 224.0.1.5 Artificial Horizons - Aviator [BXF] > 224.0.1.6 NSS - Name Service Server [BXS2] > 224.0.1.7 AUDIONEWS - Audio News Multicast [MXF2] > 224.0.1.8 SUN NIS+ Information Service [CXM3] > 224.0.1.9 MTP Multicast Transport Protocol [SXA] > 224.0.1.10 IETF-1-LOW-AUDIO [SC3] > 224.0.1.11 IETF-1-AUDIO [SC3] > 224.0.1.12 IETF-1-VIDEO [SC3] > 224.0.1.13 IETF-2-LOW-AUDIO [SC3] > 224.0.1.14 IETF-2-AUDIO [SC3] > 224.0.1.15 IETF-2-VIDEO [SC3] > 224.0.1.16 MUSIC-SERVICE [Guido van Rossum] > 224.0.1.17 SEANET-TELEMETRY [Andrew Maffei] > 224.0.1.18 SEANET-IMAGE [Andrew Maffei] > 224.0.1.19 MLOADD [Braden] > 224.0.1.20 any private experiment [JBP] > 224.0.1.21 DVMRP on MOSPF [John Moy] > 224.0.1.22 SVRLOC <veizades@ftp.com> > 224.0.1.23 XINGTV <hgxing@aol.com> > 224.0.1.24 microsoft-ds <arnoldm@microsoft.com> > 224.0.1.25 nbc-pro <bloomer@birch.crd.ge.com> > 224.0.1.26 nbc-pfn <bloomer@birch.crd.ge.com> > 224.0.1.27-224.0.1.255 Unassigned [JBP] > > 224.0.2.1 "rwho" Group (BSD) (unofficial) [JBP] > 224.0.2.2 SUN RPC PMAPPROC_CALLIT [BXE1] > > 224.0.3.000-224.0.3.255 RFE Generic Service [DXS3] > 224.0.4.000-224.0.4.255 RFE Individual Conferences [DXS3] > 224.0.5.000-224.0.5.127 CDPD Groups [Bob Brenner] > 224.0.5.128-224.0.5.255 Unassigned [IANA] > 224.0.6.000-224.0.6.127 Cornell ISIS Project [Tim Clark] > 224.0.6.128-224.0.6.255 Unassigned [IANA] > > 224.1.0.0-224.1.255.255 ST Multicast Groups [RFC1190,KS14] > 224.2.0.0-224.2.255.255 Multimedia Conference Calls [SC3] > > 224.252.0.0-224.255.255.255 DIS transient groups [Joel Snyder] > > 232.0.0.0-232.255.255.255 VMTP transient groups [RFC1045,DRC3] > > These addresses are listed in the Domain Name Service under MCAST.NET > and 224.IN-ADDR.ARPA. ...