IANA IPv4 Address Space Registry (last updated 2009-10-22) The allocation of Internet Protocol version 4 (IPv4) address space to various registries is listed here. Originally, all the IPv4 address spaces was managed directly by the IANA. Later parts of the address space were allocated to various other registries to manage for particular purposes or regional areas of the world. RFC 1466 [RFC1466] documents most of these allocations. This registry is also available in XML and XHTML formats: http://www.iana.org/assignments/ipv4-address-space/ipv4-address-space.xml http://www.iana.org/assignments/ipv4-address-space/ipv4-address-space.xhtml Prefix Designation Date Whois Status [1] Note ----- ------ ---- ----- ---------- ---- 000/8 IANA - Local Identification 1981-09 RESERVED [2] 001/8 IANA UNALLOCATED 002/8 RIPE NCC 2009-09 whois.ripe.net ALLOCATED 003/8 General Electric Company 1994-05 LEGACY 004/8 Level 3 Communications, Inc. 1992-12 LEGACY 005/8 IANA UNALLOCATED 006/8 Army Information Systems Center 1994-02 LEGACY 007/8 Administered by ARIN 1995-04 whois.arin.net LEGACY 008/8 Level 3 Communications, Inc. 1992-12 LEGACY 009/8 IBM 1992-08 LEGACY 010/8 IANA - Private Use 1995-06 RESERVED [3] 011/8 DoD Intel Information Systems 1993-05 LEGACY 012/8 AT&T Bell Laboratories 1995-06 LEGACY 013/8 Xerox Corporation 1991-09 LEGACY 014/8 IANA UNALLOCATED [4] 015/8 Hewlett-Packard Company 1994-07 LEGACY 016/8 Digital Equipment Corporation 1994-11 LEGACY 017/8 Apple Computer Inc. 1992-07 LEGACY 018/8 MIT 1994-01 LEGACY 019/8 Ford Motor Company 1995-05 LEGACY 020/8 Computer Sciences Corporation 1994-10 LEGACY 021/8 DDN-RVN 1991-07 LEGACY 022/8 Defense Information Systems Agency 1993-05 LEGACY 023/8 IANA UNALLOCATED 024/8 ARIN 2001-05 whois.arin.net ALLOCATED 025/8 UK Ministry of Defence 1995-01 whois.ripe.net LEGACY 026/8 Defense Information Systems Agency 1995-05 LEGACY 027/8 IANA UNALLOCATED 028/8 DSI-North 1992-07 LEGACY 029/8 Defense Information Systems Agency 1991-07 LEGACY 030/8 Defense Information Systems Agency 1991-07 LEGACY 031/8 IANA UNALLOCATED 032/8 AT&T Global Network Services 1994-06 LEGACY 033/8 DLA Systems Automation Center 1991-01 LEGACY 034/8 Halliburton Company 1993-03 LEGACY 035/8 MERIT Computer Network 1994-04 LEGACY 036/8 IANA UNALLOCATED 037/8 IANA UNALLOCATED 038/8 Performance Systems International 1994-09 LEGACY 039/8 IANA UNALLOCATED 040/8 Eli Lily & Company 1994-06 LEGACY 041/8 AfriNIC 2005-04 whois.afrinic.net ALLOCATED 042/8 IANA UNALLOCATED 043/8 Administered by APNIC 1991-01 LEGACY 044/8 Amateur Radio Digital Communications 1992-07 LEGACY 045/8 Interop Show Network 1995-01 LEGACY 046/8 RIPE NCC 2009-09 whois.ripe.net ALLOCATED 047/8 Bell-Northern Research 1991-01 LEGACY 048/8 Prudential Securities Inc. 1995-05 LEGACY 049/8 IANA UNALLOCATED 050/8 IANA UNALLOCATED 051/8 UK Government Department for Work and Pensions 1994-08 whois.ripe.net LEGACY 052/8 E.I. duPont de Nemours and Co., Inc. 1991-12 LEGACY 053/8 Cap Debis CCS 1993-10 LEGACY 054/8 Merck and Co., Inc. 1992-03 LEGACY 055/8 DoD Network Information Center 1995-04 LEGACY 056/8 US Postal Service 1994-06 LEGACY 057/8 SITA 1995-05 LEGACY 058/8 APNIC 2004-04 whois.apnic.net ALLOCATED 059/8 APNIC 2004-04 whois.apnic.net ALLOCATED 060/8 APNIC 2003-04 whois.apnic.net ALLOCATED 061/8 APNIC 1997-04 whois.apnic.net ALLOCATED 062/8 RIPE NCC 1997-04 whois.ripe.net ALLOCATED 063/8 ARIN 1997-04 whois.arin.net ALLOCATED 064/8 ARIN 1999-07 whois.arin.net ALLOCATED 065/8 ARIN 2000-07 whois.arin.net ALLOCATED 066/8 ARIN 2000-07 whois.arin.net ALLOCATED 067/8 ARIN 2001-05 whois.arin.net ALLOCATED 068/8 ARIN 2001-06 whois.arin.net ALLOCATED 069/8 ARIN 2002-08 whois.arin.net ALLOCATED 070/8 ARIN 2004-01 whois.arin.net ALLOCATED 071/8 ARIN 2004-08 whois.arin.net ALLOCATED 072/8 ARIN 2004-08 whois.arin.net ALLOCATED 073/8 ARIN 2005-03 whois.arin.net ALLOCATED 074/8 ARIN 2005-06 whois.arin.net ALLOCATED 075/8 ARIN 2005-06 whois.arin.net ALLOCATED 076/8 ARIN 2005-06 whois.arin.net ALLOCATED 077/8 RIPE NCC 2006-08 whois.ripe.net ALLOCATED 078/8 RIPE NCC 2006-08 whois.ripe.net ALLOCATED 079/8 RIPE NCC 2006-08 whois.ripe.net ALLOCATED 080/8 RIPE NCC 2001-04 whois.ripe.net ALLOCATED 081/8 RIPE NCC 2001-04 whois.ripe.net ALLOCATED 082/8 RIPE NCC 2002-11 whois.ripe.net ALLOCATED 083/8 RIPE NCC 2003-11 whois.ripe.net ALLOCATED 084/8 RIPE NCC 2003-11 whois.ripe.net ALLOCATED 085/8 RIPE NCC 2004-04 whois.ripe.net ALLOCATED 086/8 RIPE NCC 2004-04 whois.ripe.net ALLOCATED 087/8 RIPE NCC 2004-04 whois.ripe.net ALLOCATED 088/8 RIPE NCC 2004-04 whois.ripe.net ALLOCATED 089/8 RIPE NCC 2005-06 whois.ripe.net ALLOCATED 090/8 RIPE NCC 2005-06 whois.ripe.net ALLOCATED 091/8 RIPE NCC 2005-06 whois.ripe.net ALLOCATED 092/8 RIPE NCC 2007-03 whois.ripe.net ALLOCATED 093/8 RIPE NCC 2007-03 whois.ripe.net ALLOCATED 094/8 RIPE NCC 2007-07 whois.ripe.net ALLOCATED 095/8 RIPE NCC 2007-07 whois.ripe.net ALLOCATED 096/8 ARIN 2006-10 whois.arin.net ALLOCATED 097/8 ARIN 2006-10 whois.arin.net ALLOCATED 098/8 ARIN 2006-10 whois.arin.net ALLOCATED 099/8 ARIN 2006-10 whois.arin.net ALLOCATED 100/8 IANA UNALLOCATED 101/8 IANA UNALLOCATED 102/8 IANA UNALLOCATED 103/8 IANA UNALLOCATED 104/8 IANA UNALLOCATED 105/8 IANA UNALLOCATED 106/8 IANA UNALLOCATED 107/8 IANA UNALLOCATED 108/8 ARIN 2008-12 whois.arin.net ALLOCATED 109/8 RIPE NCC 2009-01 whois.ripe.net ALLOCATED 110/8 APNIC 2008-11 whois.apnic.net ALLOCATED 111/8 APNIC 2008-11 whois.apnic.net ALLOCATED 112/8 APNIC 2008-05 whois.apnic.net ALLOCATED 113/8 APNIC 2008-05 whois.apnic.net ALLOCATED 114/8 APNIC 2007-10 whois.apnic.net ALLOCATED 115/8 APNIC 2007-10 whois.apnic.net ALLOCATED 116/8 APNIC 2007-01 whois.apnic.net ALLOCATED 117/8 APNIC 2007-01 whois.apnic.net ALLOCATED 118/8 APNIC 2007-01 whois.apnic.net ALLOCATED 119/8 APNIC 2007-01 whois.apnic.net ALLOCATED 120/8 APNIC 2007-01 whois.apnic.net ALLOCATED 121/8 APNIC 2006-01 whois.apnic.net ALLOCATED 122/8 APNIC 2006-01 whois.apnic.net ALLOCATED 123/8 APNIC 2006-01 whois.apnic.net ALLOCATED 124/8 APNIC 2005-01 whois.apnic.net ALLOCATED 125/8 APNIC 2005-01 whois.apnic.net ALLOCATED 126/8 APNIC 2005-01 whois.apnic.net ALLOCATED 127/8 IANA - Loopback 1981-09 RESERVED [5] 128/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 129/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 130/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 131/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 132/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 133/8 Administered by APNIC 1997-03 whois.apnic.net LEGACY 134/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 135/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 136/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 137/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 138/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 139/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 140/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 141/8 Administered by RIPE NCC 1993-05 whois.ripe.net LEGACY 142/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 143/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 144/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 145/8 Administered by RIPE NCC 1993-05 whois.ripe.net LEGACY 146/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 147/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 148/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 149/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 150/8 Administered by APNIC 1993-05 whois.apnic.net LEGACY 151/8 Administered by RIPE NCC 1993-05 whois.ripe.net LEGACY 152/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 153/8 Administered by APNIC 1993-05 whois.apnic.net LEGACY 154/8 Administered by AfriNIC 1993-05 whois.afrinic.net LEGACY 155/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 156/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 157/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 158/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 159/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 160/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 161/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 162/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 163/8 Administered by APNIC 1993-05 whois.apnic.net LEGACY 164/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 165/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 166/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 167/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 168/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 169/8 Administered by ARIN 1993-05 whois.arin.net LEGACY [6] 170/8 Administered by ARIN 1993-05 whois.arin.net LEGACY 171/8 Administered by APNIC 1993-05 whois.apnic.net LEGACY 172/8 Administered by ARIN 1993-05 whois.arin.net LEGACY [7] 173/8 ARIN 2008-02 whois.arin.net ALLOCATED 174/8 ARIN 2008-02 whois.arin.net ALLOCATED 175/8 APNIC 2009-08 whois.apnic.net ALLOCATED 176/8 IANA UNALLOCATED 177/8 IANA UNALLOCATED 178/8 RIPE NCC 2009-01 whois.ripe.net ALLOCATED 179/8 IANA UNALLOCATED 180/8 APNIC 2009-04 whois.apnic.net ALLOCATED 181/8 IANA UNALLOCATED 182/8 APNIC 2009-08 whois.apnic.net ALLOCATED 183/8 APNIC 2009-04 whois.apnic.net ALLOCATED 184/8 ARIN 2008-12 whois.arin.net ALLOCATED 185/8 IANA UNALLOCATED 186/8 LACNIC 2007-09 whois.lacnic.net ALLOCATED 187/8 LACNIC 2007-09 whois.lacnic.net ALLOCATED 188/8 Administered by RIPE NCC 1993-05 whois.ripe.net LEGACY 189/8 LACNIC 1995-06 whois.lacnic.net ALLOCATED 190/8 LACNIC 1995-06 whois.lacnic.net ALLOCATED 191/8 Administered by LACNIC 1993-05 whois.lacnic.net LEGACY 192/8 Administered by ARIN 1993-05 whois.arin.net LEGACY [8] 193/8 RIPE NCC 1993-05 whois.ripe.net ALLOCATED 194/8 RIPE NCC 1993-05 whois.ripe.net ALLOCATED 195/8 RIPE NCC 1993-05 whois.ripe.net ALLOCATED 196/8 Administered by AfriNIC 1993-05 whois.afrinic.net LEGACY 197/8 AfriNIC 2008-10 whois.afrinic.net ALLOCATED 198/8 Administered by ARIN 1993-05 whois.arin.net LEGACY [9] 199/8 ARIN 1993-05 whois.arin.net ALLOCATED 200/8 LACNIC 2002-11 whois.lacnic.net ALLOCATED 201/8 LACNIC 2003-04 whois.lacnic.net ALLOCATED 202/8 APNIC 1993-05 whois.apnic.net ALLOCATED 203/8 APNIC 1993-05 whois.apnic.net ALLOCATED [10] 204/8 ARIN 1994-03 whois.arin.net ALLOCATED 205/8 ARIN 1994-03 whois.arin.net ALLOCATED 206/8 ARIN 1995-04 whois.arin.net ALLOCATED 207/8 ARIN 1995-11 whois.arin.net ALLOCATED 208/8 ARIN 1996-04 whois.arin.net ALLOCATED 209/8 ARIN 1996-06 whois.arin.net ALLOCATED 210/8 APNIC 1996-06 whois.apnic.net ALLOCATED 211/8 APNIC 1996-06 whois.apnic.net ALLOCATED 212/8 RIPE NCC 1997-10 whois.ripe.net ALLOCATED 213/8 RIPE NCC 1993-10 whois.ripe.net ALLOCATED 214/8 US-DOD 1998-03 LEGACY 215/8 US-DOD 1998-03 LEGACY 216/8 ARIN 1998-04 whois.arin.net ALLOCATED 217/8 RIPE NCC 2000-06 whois.ripe.net ALLOCATED 218/8 APNIC 2000-12 whois.apnic.net ALLOCATED 219/8 APNIC 2001-09 whois.apnic.net ALLOCATED 220/8 APNIC 2001-12 whois.apnic.net ALLOCATED 221/8 APNIC 2002-07 whois.apnic.net ALLOCATED 222/8 APNIC 2003-02 whois.apnic.net ALLOCATED 223/8 IANA UNALLOCATED 224/8 Multicast 1981-09 RESERVED [11] 225/8 Multicast 1981-09 RESERVED [11] 226/8 Multicast 1981-09 RESERVED [11] 227/8 Multicast 1981-09 RESERVED [11] 228/8 Multicast 1981-09 RESERVED [11] 229/8 Multicast 1981-09 RESERVED [11] 230/8 Multicast 1981-09 RESERVED [11] 231/8 Multicast 1981-09 RESERVED [11] 232/8 Multicast 1981-09 RESERVED [11] 233/8 Multicast 1981-09 RESERVED [11] 234/8 Multicast 1981-09 RESERVED [11] 235/8 Multicast 1981-09 RESERVED [11] 236/8 Multicast 1981-09 RESERVED [11] 237/8 Multicast 1981-09 RESERVED [11] 238/8 Multicast 1981-09 RESERVED [11] 239/8 Multicast 1981-09 RESERVED [11] 240/8 Future use 1981-09 RESERVED [12] 241/8 Future use 1981-09 RESERVED [12] 242/8 Future use 1981-09 RESERVED [12] 243/8 Future use 1981-09 RESERVED [12] 244/8 Future use 1981-09 RESERVED [12] 245/8 Future use 1981-09 RESERVED [12] 246/8 Future use 1981-09 RESERVED [12] 247/8 Future use 1981-09 RESERVED [12] 248/8 Future use 1981-09 RESERVED [12] 249/8 Future use 1981-09 RESERVED [12] 250/8 Future use 1981-09 RESERVED [12] 251/8 Future use 1981-09 RESERVED [12] 252/8 Future use 1981-09 RESERVED [12] 253/8 Future use 1981-09 RESERVED [12] 254/8 Future use 1981-09 RESERVED [12] 255/8 Future use 1981-09 RESERVED [12] Notes ----- [1] Indicates the status of address blocks as follows: RESERVED: designated by the IETF for specific non-unicast purposes as noted. LEGACY: allocated by the central Internet Registry (IR) prior to the Regional Internet Registries (RIRs). This address space is now administered by individual RIRs as noted, including maintenance of WHOIS Directory and reverse DNS records. Assignments from these blocks are distributed globally on a regional basis. ALLOCATED: delegated entirely to specific RIR as indicated. UNALLOCATED: not yet allocated or reserved. [2] 0.0.0.0/8 reserved for self-identification [RFC-iana-rfc3330bis-11.txt] [3] Reserved for Private-Use Networks [RFC1918] [4] This was reserved for Public Data Networks [RFC1356] See: http://www.iana.org/assignments/public-data-network-numbers It was recovered in February 2008. [5] 127.0.0.0/8 is reserved for Loopback [RFC-iana-rfc3330bis-11.txt] [6] 169.254.0.0/16 reserved for Link Local [RFC-iana-rfc3330bis-11.txt] [7] 172.16.0.0/12 reserved for Private-Use Networks [RFC1918] [8] 192.0.2.0/24 reserved for TEST-NET-1 [RFC-iana-ipv4-examples-02.txt] 192.88.99.0/24 reserved for 6to4 Relay Anycast [RFC3068] 192.168.0.0/16 reserved for Private-Use Networks [RFC1918] [9] 198.18.0.0/15 reserved for Network Interconnect Device Benchmark Testing [RFC-iana-rfc3330bis-11.txt] 198.51.100.0/24 reserved for TEST-NET-2 [RFC-iana-ipv4-examples-02.txt] [10] 203.0.113.0/24 reserved for TEST-NET-3 [RFC-iana-ipv4-examples-02.txt] [11] Multicast (formerly "Class D") [RFC1700] See: http://www.iana.org/assignments/multicast-addresses [12] Reserved for future use (formerly "Class E") [RFC1700] Reference --------- [RFC1356] Malis, A., Robinson, D., and R. Ullmann, "Multiprotocol Interconnect on X.25 and ISDN in the Packet Mode", RFC 1356, August 1992. [RFC1466] Gerich, E., "Guidelines for Management of IP Address Space", RFC 1466, May 1993. [RFC1700] Reynolds, J. and J. Postel, "Assigned Numbers", RFC1700, October 1994. [RFC1918] Rekhter, Y., Moskowitz, R., Karrenberg, D., Groot, G., and E. Lear, "Address Allocation for Private Internets", BCP 5, RFC 1918, February 1996. [RFC2050] Hubbard, K., Kosters, M., Conrad, D., Karrenberg, D., and J. Postel, "INTERNET REGISTRY IP ALLOCATION GUIDELINES", BCP 12, RFC 2050, November 1996. [RFC3068] Huitema, C., "An Anycast Prefix for 6to4 Relay Routers", RFC 3068, June 2001. [RFC3171] Albanna, Z., Almeroth, K., Meyer, D., and M. Schipper, "IANA Guidelines for IPv4 Multicast Address Assignments", BCP 51, RFC 3171, August 2001. [RFC3330] IANA, "Special-Use IPv4 Addresses", RFC 3330, September 2002.