List of assigned /8 IPv4 address blocks

Some large /8 blocks of IPv4 addresses, the former Class A network blocks, are assigned in whole to single organizations or related groups of organizations, either by the Internet Corporation for Assigned Names and Numbers (ICANN), through the Internet Assigned Numbers Authority (IANA), or a regional Internet registry.

Each /8 block contains 16,777,216 addresses.

As IPv4 address exhaustion has advanced to its final stages, some organizations, such as Stanford University, formerly using 36.0.0.0/8, have returned their allocated blocks to assist in the delay of the exhaustion date.

List of reserved /8 blocks

Block Organization IANA Date RIR Date Notes
0.0.0.0/8 IANA - Local Identification 1981-09 Originally IANA - Reserved 1981-09. 0.0.0.0/8 reserved for self-identification (RFC 5735).
10.0.0.0/8 IANA - Private Use 1995-06 Reserved for Private-Use Networks (RFC 1918). Formerly ARPANET.[1]
127.0.0.0/8 IANA - Loopback 1981-09 127.0.0.0/8 is reserved for Loopback (RFC 5735).
224.0.0.0/8–239.0.0.0/8 Multicast 1981-09 1991-05-22 Multicast (formerly "Class D") (RFC 5771) registered in . 224.0.0.0/4.
240.0.0.0/8–255.0.0.0/8 Future Use 1981-09 Reserved for future use (formerly "Class E") (RFC 1112). 255.255.255.255 is reserved for "limited broadcast" destination address (RFC 919) and (RFC 922). 240.0.0.0/4.

List of assigned /8 blocks

Block Organization IANA Date RIR Date Notes
3.0.0.0/8 General Electric Company 1994-05 1988-02-23
4.0.0.0/8 Level 3 Communications, Inc. 1992-12 1992-12-01 Originally Bolt Beranek and Newman Inc. (then GTE, then Genuity) 1992-12. Updated to Level 3 Communications, Inc. in 2007-04.
7.0.0.0/8 Administered by ARIN 1995-04 1997-11-24 Formerly IANA - Reserved 1995-04. Entirely assigned to DoD Network Information Center (DNIC) 1997-11-24. Updated to Administered by ARIN not before 2007.
8.0.0.0/8 Level 3 Communications, Inc. 1992-12 1992-12-01 Originally Bolt Beranek and Newman Inc. (then GTE, then Genuity) 1992-12. Updated to Level 3 Communications, Inc. in 2007-04.
9.0.0.0/8 IBM 1992-08 1988-12-16
12.0.0.0/8 AT&T Services 1995-06 1983-08-23 Originally AT&T Bell Laboratories, retained by AT&T when Bell Labs was spun off to Lucent Technologies in 1996.
13.0.0.0/8 Xerox Corporation 1991-09 1986-04-25 Xerox Palo Alto Research Center (PARC).
15.0.0.0/8 Hewlett-Packard Company 1994-07 1994-07-01
16.0.0.0/8 Digital Equipment Corporation 1994-11 1989-05-18 Digital Equipment Corporation, then Compaq, then Hewlett-Packard.
17.0.0.0/8 Apple Inc. 1992-07 1990-04-16
18.0.0.0/8 MIT 1994-01 1994-01-01
19.0.0.0/8 Ford Motor Company 1995-05 1988-06-15
20.0.0.0/8 Computer Sciences Corporation 1994-10 1989-09-04
25.0.0.0/8 UK Ministry of Defence 1995-01 1985-01-28 Originally Royal Signals and Radar Establishment. Updated to UK Ministry of Defence in 2006-01.
32.0.0.0/8 AT&T Global Network Services 1994-06 1990-05-30 Originally Norsk Informasjonsteknologi. IBM acquired Norsk Informasjonsteknologi (Norway) in 1995. Updated to AT&T Global Network Services in 2007-08.
34.0.0.0/8 Halliburton Company 1993-03 1991-03-11
35.0.0.0/8 MERIT Computer Network 1994-04 1994-04-01
38.0.0.0/8 PSINet, Inc. 1994-09 1991-04-16 PSINet, then Cogent Communications.
40.0.0.0/8 Eli Lilly & Company 1994-06 1991-04-23
44.0.0.0/8 Amateur Radio Digital Communications 1992-07 1992-07-01
47.0.0.0/8 Bell-Northern Research 1991-01 1989-01-06 Bell-Northern Research, formerly absorbed into Nortel, portions of which are now owned by Bell Aliant, Cablevision, Microsoft, and Vodafone.
48.0.0.0/8 Prudential Securities Inc. 1995-05 1990-12-07 The Prudential Insurance Company of America.
51.0.0.0/8 UK Government Department for Work and Pensions 1994-08 1991-09-16
52.0.0.0/8 E.I. duPont de Nemours and Co., Inc. 1991-12 1991-12-19
53.0.0.0/8 Cap Debis CCS 1993-10 1992-03-17 Cap Debis CCS (Daimler AG).
54.0.0.0/8 Merck and Co., Inc. 1992-03 1992-03-17 Merck has entered into a private sale with Amazon.com for some of their IP address space.[2] They unnumbered 48 /16s as of 01/2012, an additional 16 /16s as of 05/2013, and an additional 16 /16s as of 11/2013 leaving them with about 70% of their original /8.
56.0.0.0/8 US Postal Service 1994-06 1992-11-02
57.0.0.0/8 SITA 1995-05 1993-06-21

List of assigned /8 blocks to the United States Department of Defense

Block Organization IANA Date RIR Date Notes
6.0.0.0/8 Army Information Systems Center 1994-02 1994-02-01 Headquarters, USAISC.
11.0.0.0/8 DoD Intel Information Systems 1993-05 1984-01-19
21.0.0.0/8 DDN-RVN 1991-07 1991-07-01 DoD Network Information Center (DNIC).
22.0.0.0/8 Defense Information Systems Agency 1993-05 1989-06-26 DoD Network Information Center (DNIC).
26.0.0.0/8 Defense Information Systems Agency 1995-05 1995-05-01 DoD Network Information Center (DNIC).
28.0.0.0/8 DSI-North 1992-07 DoD Network Information Center (DNIC).
29.0.0.0/8 Defense Information Systems Agency 1991-07 1991-07-01 DoD Network Information Center (DNIC).
30.0.0.0/8 Defense Information Systems Agency 1991-07 1991-07-01 DoD Network Information Center (DNIC).
33.0.0.0/8 DLA Systems Automation Center 1991-01 1991-01-01 DoD Network Information Center (DNIC).
55.0.0.0/8 DoD Network Information Center 1995-04 1996-10-26 Headquarters, USAISC. Formerly Boeing Computer Services 1995-04. Updated to DoD Network Information Center in 2007-02.
214.0.0.0/8 US-DOD 1998-03 1998-03-27 DoD Network Information Center (DNIC).
215.0.0.0/8 US-DOD 1998-03 1998-06-05 DoD Network Information Center (DNIC).

List of assigned /8 blocks to the Regional Internet Registries

Block Organization IANA Date RIR Date Notes
1.0.0.0/8 APNIC 2010-01 Formerly IANA - Reserved 1981-09.
2.0.0.0/8 RIPE NCC 2009-10 Formerly IANA - Reserved 1981-09.
5.0.0.0/8 RIPE NCC Formerly IANA - Reserved 1995-07.
14.0.0.0/8 APNIC 2010-04 Starting 1991-06-01, was used to map Public Data Network (X.121) addresses to IP addresses. Returned to IANA 2008-01-22. This network was reclaimed by IANA in 2007 and was subsequently re-allocated in 2010. See RFC 877 and RFC 1356 for historical information.[3]
23.0.0.0/8 ARIN 2010-11 Formerly IANA - Reserved 1995-07.
24.0.0.0/8 ARIN 2001-05 2001-05-01 Formerly IANA - Cable Block 1995-07, then ARIN - Cable Block 2001-05.[4] Updated to ARIN not before 2007.
27.0.0.0/8 APNIC 2010-01 Formerly IANA - Reserved 1995-04.
31.0.0.0/8 RIPE NCC 2010-05 2010-05-18 Formerly IANA - Reserved 1991-04.
36.0.0.0/8 APNIC 2010-10 Formerly Stanford University 1993-04, then IANA - Reserved 2000-07.
37.0.0.0/8 RIPE NCC 2010-11 Formerly IANA - Reserved 1995-04.
39.0.0.0/8 APNIC 2011-01 Formerly IANA - Reserved 1995-04.
41.0.0.0/8 AfriNIC 2005-04 Formerly IANA - Reserved 1995-05.
42.0.0.0/8 APNIC 2010-10 Formerly IANA - Reserved 1995-07.
43.0.0.0/8 APNIC 1991-01 1989-02-21 Originally Japan Inet 1991-01 (IANA Date) or 1989-02-21 (RIR Date). Administered by APNIC not before 2007.
45.0.0.0/8 ARIN 1995-01 1991-09-09 Formerly Interop Show Network 1995-01 or 1991-09-09 (RIR Date). Returned to ARIN in 2010-10 except a /15 block. In 2011 it will become available for distribution (or possibly be returned to the IANA, depending on the global policy in effect at that time).[5]
46.0.0.0/8 RIPE NCC 2009-09 Formerly Bolt Beranek and Newman Inc. 1992-12. Returned to IANA in 2007-04.[6] Updated to IANA - Reserved in 2007-04.
49.0.0.0/8 APNIC 2010-08 Formerly Joint Technical Command (Returned to IANA Mar 98) 1994-05. Updated to IANA - Reserved in 2007-05.
50.0.0.0/8 ARIN 2010-02 Formerly Joint Technical Command (Returned to IANA Mar 98) 1994-05. Updated to IANA - Reserved in 2007-05.
60.0.0.0/8 APNIC 2010-01 Formerly IANA - Reserved 1981-09.
61.0.0.0/8 APNIC 2010-01 Formerly IANA - Reserved 1981-09.
88.0.0.0/8 APNIC 2010-01 Formerly IANA - Reserved 1981-09.
111.0.0.0/8 APNIC 2010-01 Formerly IANA - Reserved 1981-09.
114.0.0.0/8 APNIC 2010-01 Formerly IANA - Reserved 1981-09.
107.0.0.0/8 ARIN 2010-02 2010-02-11
120.0.0.0/8 APNIC 2010-01 Formerly IANA - Reserved 1981-09.
128.0.0.0/8 RIPE NCC Various Registries (Maintained by RIPE NCC). 128.0.0.0 is the start address of formerly "Class B".
169.0.0.0/8 ARIN 1993-05 1993-05-01 Various Registries (Maintained by ARIN). 169.254.0.0/16 (169.254.0.0–169.254.255.255) reserved for link-local addressing (RFC 5735).
172.0.0.0/8 ARIN 1993-05 1993-05-01 Various Registries (Maintained by ARIN). 172.16.0.0/12 (172.16.0.0–172.31.255.255) reserved for private networks (RFC 1918).
183.0.0.0/8 APNIC 2010-01 Formerly IANA - Reserved 1981-09.
192.0.0.0/8 ARIN 1993-05 1993-05-01 Various Registries (Maintained by ARIN). 192.0.2.0/24 reserved for TEST-NET-1 (RFC 5737). 192.88.99.0/24 reserved for 6to4 Relay Anycast (RFC 3068). 192.168.0.0/16 (192.168.0.0–192.168.255.255) reserved for private networks (RFC 1918). 192.0.0.0/24 reserved for IANA IPv4 Special Purpose Address Registry (RFC 5736). 192.0.0.0 is the start address of formerly "Class C".
198.0.0.0/8 ARIN 1993-05 Various Registries (Maintained by ARIN). 198.18.0.0/15 reserved for Network Interconnect Device Benchmark Testing (RFC 5735). 198.51.100.0/24 reserved for TEST-NET-2 (RFC 5737).
202.0.0.0/8 APNIC 2009-10 202.123.0.0/19 transferred to AfriNIC
203.0.0.0/8 APNIC 1993-05 203.0.113.0/24 reserved for TEST-NET-3 (RFC 5737).
217.0.0.0/8 RIPE NCC 2013-07 2013-07-29 RIPE Network Coordination Centre
218.0.0.0/8 APNIC 2010-01 Formerly IANA - Reserved 1981-09.

Note that this list does not include all assignments of /8 blocks to the regional or national Internet registries.

See also

Notes

References