Online Technical Library
To assist our customers with self-study, independent troubleshooting, and for convenient
cross-referencing of information we provide access to an online technical library.
Browse our technical library
Browse our technical library
Space Weather Information
We've all wanted to blame network or server performance on Solar Flares! Well, Here's your chance. CIT maintains a comprehensive geomagnetic and solar information center. You can access this information through our Space Weather Information Page. And, yes, it could be what's causing your problems.
See Space Weather
See Space Weather
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Internet Protocol Address Space
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
documents most of these allocations.
Address Block Registry - Purpose Date --------------- --------------------------------------- ------ 000/8 IANA - Reserved Sep 81 001/8 IANA - Reserved Sep 81 002/8 IANA - Reserved Sep 81 003/8 General Electric Company May 94 004/8 Bolt Beranek and Newman Inc. Dec 92 005/8 IANA - Reserved Jul 95 006/8 Army Information Systems Center Feb 94 007/8 IANA - Reserved Apr 95 008/8 Bolt Beranek and Newman Inc. Dec 92 009/8 IBM Aug 92 010/8 IANA - Private Use Jun 95 011/8 DoD Intel Information Systems May 93 012/8 AT&T Bell Laboratories Jun 95 013/8 Xerox Corporation Sep 91 014/8 IANA - Public Data Network Jun 91 015/8 Hewlett-Packard Company Jul 94 016/8 Digital Equipment Corporation Nov 94 017/8 Apple Computer Inc. Jul 92 018/8 MIT Jan 94 019/8 Ford Motor Company May 95 020/8 Computer Sciences Corporation Oct 94 021/8 DDN-RVN Jul 91 022/8 Defense Information Systems Agency May 93 023/8 IANA - Reserved Jul 95 024/8 IANA - Cable Block Jul 95 025/8 Royal Signals and Radar Establishment Jan 95 026/8 Defense Information Systems Agency May 95 027/8 IANA - Reserved Apr 95 028/8 DSI-North Jul 92 029/8 Defense Information Systems Agency Jul 91 030/8 Defense Information Systems Agency Jul 91 031/8 IANA - Reserved Apr 99 032/8 Norsk Informasjonsteknologi Jun 94 033/8 DLA Systems Automation Center Jan 91 034/8 Halliburton Company Mar 93 035/8 MERIT Computer Network Apr 94 036/8 Stanford University Apr 93 037/8 IANA - Reserved Apr 95 038/8 Performance Systems International Sep 94 039/8 IANA - Reserved Apr 95 040/8 Eli Lily and Company Jun 94 041/8 IANA - Reserved May 95 042/8 IANA - Reserved Jul 95 043/8 Japan Inet Jan 91 044/8 Amateur Radio Digital Communications Jul 92 045/8 Interop Show Network Jan 95 046/8 Bolt Beranek and Newman Inc. Dec 92 047/8 Bell-Northern Research Jan 91 048/8 Prudential Securities Inc. May 95 049/8 Joint Technical Command May 94 Returned to IANA Mar 98 050/8 Joint Technical Command May 94 Returned to IANA Mar 98 051/8 Deparment of Social Security of UK Aug 94 052/8 E.I. duPont de Nemours and Co., Inc. Dec 91 053/8 Cap Debis CCS Oct 93 054/8 Merck and Co., Inc. Mar 92 055/8 Boeing Computer Services Apr 95 056/8 U.S. Postal Service Jun 94 057/8 SITA May 95 058/8 IANA - Reserved Sep 81 059/8 IANA - Reserved Sep 81 060/8 IANA - Reserved Sep 81 061/8 APNIC - Pacific Rim Apr 97 062/8 RIPE NCC - Europe Apr 97 063/8 ARIN Apr 97 064-095/8 IANA - Reserved Sep 81 096-126/8 IANA - Reserved Sep 81 127/8 IANA - Reserved Sep 81 128-191/8 Various Registries May 93 192/8 Various Registries - MultiRegional May 93 193/8 RIPE NCC - Europe May 93 194/8 RIPE NCC - Europe May 93 195/8 RIPE NCC - Europe May 93 196/8 Various Registries May 93 197/8 IANA - Reserved May 93 198/8 Various Registries May 93 199/8 ARIN - North America May 93 200/8 ARIN - Central and South America May 93 201/8 Reserved - Central and South America May 93 202/8 APNIC - Pacific Rim May 93 203/8 APNIC - Pacific Rim May 93 204/8 ARIN - North America Mar 94 205/8 ARIN - North America Mar 94 206/8 ARIN - North America Apr 95 207/8 ARIN - North America Nov 95 208/8 ARIN - North America Apr 96 209/8 ARIN - North America Jun 96 210/8 APNIC - Pacific Rim Jun 96 211/8 APNIC - Pacific Rim Jun 96 212/8 RIPE NCC - Europe Oct 97 213/8 RIPE NCC - Europe Mar 99 214/8 US-DOD Mar 98 215/8 US-DOD Mar 98 216/8 ARIN - North America Apr 98 217/8 IANA - Reserved Sep 81 218-223/8 IANA - Reserved Sep 81 224-239/8 IANA - Multicast Sep 81 240-255/8 IANA - Reserved Sep 81