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IPv4 Address Space

IANA IPv4 Address Space Allocation and Assignment Status. View Regional Internet Registry (RIR) assignments and reserved address blocks.

Data source: IANA IPv4 Address Space Registry (Key allocations shown)

256
Total Blocks
129
Allocated
35
Reserved
92
Legacy
Showing 256 of 256 blocks
PrefixDesignationDateStatusRIRWHOISRDAP
0.0.0.0/8IANA - Local Identification1981-09RESERVEDIANA--
1.0.0.0/8APNIC2010-01ALLOCATEDAPNICwhois.apnic.netLink
2.0.0.0/8RIPE NCC2009-09ALLOCATEDRIPE NCCwhois.ripe.netLink
3.0.0.0/8Administered by ARIN1994-05LEGACYARINwhois.arin.netLink
4.0.0.0/8Administered by ARIN1992-12LEGACYARINwhois.arin.netLink
5.0.0.0/8RIPE NCC2010-11ALLOCATEDRIPE NCCwhois.ripe.netLink
6.0.0.0/8Army Information Systems Center1994-02LEGACYARINwhois.arin.netLink
7.0.0.0/8Administered by ARIN1995-04LEGACYARINwhois.arin.netLink
8.0.0.0/8Administered by ARIN1992-12LEGACYARINwhois.arin.netLink
9.0.0.0/8Administered by ARIN1992-08LEGACYARINwhois.arin.netLink
10.0.0.0/8IANA - Private Use1995-06RESERVEDIANA--
11.0.0.0/8DoD Intel Information Systems1993-05LEGACYARINwhois.arin.netLink
12.0.0.0/8AT&T Bell Laboratories1995-06LEGACYARINwhois.arin.netLink
13.0.0.0/8Administered by ARIN1991-09LEGACYARINwhois.arin.netLink
14.0.0.0/8APNIC2010-04ALLOCATEDAPNICwhois.apnic.netLink
15.0.0.0/8Administered by ARIN1994-07LEGACYARINwhois.arin.netLink
16.0.0.0/8Administered by ARIN1994-11LEGACYARINwhois.arin.netLink
17.0.0.0/8Apple Computer Inc.1992-07LEGACYARINwhois.arin.netLink
18.0.0.0/8Administered by ARIN1994-01LEGACYARINwhois.arin.netLink
19.0.0.0/8Ford Motor Company1995-05LEGACYARINwhois.arin.netLink
20.0.0.0/8Administered by ARIN1994-10LEGACYARINwhois.arin.netLink
21.0.0.0/8DDN-RVN1991-07LEGACYARINwhois.arin.netLink
22.0.0.0/8Defense Information Systems Agency1993-05LEGACYARINwhois.arin.netLink
23.0.0.0/8ARIN2010-11ALLOCATEDARINwhois.arin.netLink
24.0.0.0/8ARIN2001-05ALLOCATEDARINwhois.arin.netLink
25.0.0.0/8Administered by RIPE NCC1995-01LEGACYRIPE NCCwhois.ripe.netLink
26.0.0.0/8Defense Information Systems Agency1995-05LEGACYARINwhois.arin.netLink
27.0.0.0/8APNIC2010-01ALLOCATEDAPNICwhois.apnic.netLink
28.0.0.0/8DSI-North1992-07LEGACYARINwhois.arin.netLink
29.0.0.0/8Defense Information Systems Agency1991-07LEGACYARINwhois.arin.netLink
30.0.0.0/8Defense Information Systems Agency1991-07LEGACYARINwhois.arin.netLink
31.0.0.0/8RIPE NCC2010-05ALLOCATEDRIPE NCCwhois.ripe.netLink
32.0.0.0/8Administered by ARIN1994-06LEGACYARINwhois.arin.netLink
33.0.0.0/8DLA Systems Automation Center1991-01LEGACYARINwhois.arin.netLink
34.0.0.0/8Administered by ARIN1993-03LEGACYARINwhois.arin.netLink
35.0.0.0/8Administered by ARIN1994-04LEGACYARINwhois.arin.netLink
36.0.0.0/8APNIC2010-10ALLOCATEDAPNICwhois.apnic.netLink
37.0.0.0/8RIPE NCC2010-11ALLOCATEDRIPE NCCwhois.ripe.netLink
38.0.0.0/8PSINet, Inc.1994-09LEGACYARINwhois.arin.netLink
39.0.0.0/8APNIC2011-01ALLOCATEDAPNICwhois.apnic.netLink
40.0.0.0/8Administered by ARIN1994-06LEGACYARINwhois.arin.netLink
41.0.0.0/8AFRINIC2005-04ALLOCATEDAFRINICwhois.afrinic.netLink
42.0.0.0/8APNIC2010-10ALLOCATEDAPNICwhois.apnic.netLink
43.0.0.0/8Administered by APNIC1991-01LEGACYAPNICwhois.apnic.netLink
44.0.0.0/8Administered by ARIN1992-07LEGACYARINwhois.arin.netLink
45.0.0.0/8Administered by ARIN1995-01LEGACYARINwhois.arin.netLink
46.0.0.0/8RIPE NCC2009-09ALLOCATEDRIPE NCCwhois.ripe.netLink
47.0.0.0/8Administered by ARIN1991-01LEGACYARINwhois.arin.netLink
48.0.0.0/8Administered by ARIN1995-05LEGACYARINwhois.arin.netLink
49.0.0.0/8APNIC2010-08ALLOCATEDAPNICwhois.apnic.netLink
50.0.0.0/8ARIN2010-02ALLOCATEDARINwhois.arin.netLink
51.0.0.0/8Administered by RIPE NCC1994-08LEGACYRIPE NCCwhois.ripe.netLink
52.0.0.0/8Administered by ARIN1991-12LEGACYARINwhois.arin.netLink
53.0.0.0/8Daimler AG1993-10LEGACYIANAwhois.ripe.netLink
54.0.0.0/8Administered by ARIN1992-03LEGACYARINwhois.arin.netLink
55.0.0.0/8DoD Network Information Center1995-04LEGACYARINwhois.arin.netLink
56.0.0.0/8Administered by ARIN1994-06LEGACYARINwhois.arin.netLink
57.0.0.0/8Administered by RIPE NCC1995-05LEGACYRIPE NCCwhois.ripe.netLink
58.0.0.0/8APNIC2004-04ALLOCATEDAPNICwhois.apnic.netLink
59.0.0.0/8APNIC2004-04ALLOCATEDAPNICwhois.apnic.netLink
60.0.0.0/8APNIC2003-04ALLOCATEDAPNICwhois.apnic.netLink
61.0.0.0/8APNIC1997-04ALLOCATEDAPNICwhois.apnic.netLink
62.0.0.0/8RIPE NCC1997-04ALLOCATEDRIPE NCCwhois.ripe.netLink
63.0.0.0/8ARIN1997-04ALLOCATEDARINwhois.arin.netLink
64.0.0.0/8ARIN1999-07ALLOCATEDARINwhois.arin.netLink
65.0.0.0/8ARIN2000-07ALLOCATEDARINwhois.arin.netLink
66.0.0.0/8ARIN2000-07ALLOCATEDARINwhois.arin.netLink
67.0.0.0/8ARIN2001-05ALLOCATEDARINwhois.arin.netLink
68.0.0.0/8ARIN2001-06ALLOCATEDARINwhois.arin.netLink
69.0.0.0/8ARIN2002-08ALLOCATEDARINwhois.arin.netLink
70.0.0.0/8ARIN2004-01ALLOCATEDARINwhois.arin.netLink
71.0.0.0/8ARIN2004-08ALLOCATEDARINwhois.arin.netLink
72.0.0.0/8ARIN2004-08ALLOCATEDARINwhois.arin.netLink
73.0.0.0/8ARIN2005-03ALLOCATEDARINwhois.arin.netLink
74.0.0.0/8ARIN2005-06ALLOCATEDARINwhois.arin.netLink
75.0.0.0/8ARIN2005-06ALLOCATEDARINwhois.arin.netLink
76.0.0.0/8ARIN2005-06ALLOCATEDARINwhois.arin.netLink
77.0.0.0/8RIPE NCC2006-08ALLOCATEDRIPE NCCwhois.ripe.netLink
78.0.0.0/8RIPE NCC2006-08ALLOCATEDRIPE NCCwhois.ripe.netLink
79.0.0.0/8RIPE NCC2006-08ALLOCATEDRIPE NCCwhois.ripe.netLink
80.0.0.0/8RIPE NCC2001-04ALLOCATEDRIPE NCCwhois.ripe.netLink
81.0.0.0/8RIPE NCC2001-04ALLOCATEDRIPE NCCwhois.ripe.netLink
82.0.0.0/8RIPE NCC2002-11ALLOCATEDRIPE NCCwhois.ripe.netLink
83.0.0.0/8RIPE NCC2003-11ALLOCATEDRIPE NCCwhois.ripe.netLink
84.0.0.0/8RIPE NCC2003-11ALLOCATEDRIPE NCCwhois.ripe.netLink
85.0.0.0/8RIPE NCC2004-04ALLOCATEDRIPE NCCwhois.ripe.netLink
86.0.0.0/8RIPE NCC2004-04ALLOCATEDRIPE NCCwhois.ripe.netLink
87.0.0.0/8RIPE NCC2004-04ALLOCATEDRIPE NCCwhois.ripe.netLink
88.0.0.0/8RIPE NCC2004-04ALLOCATEDRIPE NCCwhois.ripe.netLink
89.0.0.0/8RIPE NCC2005-06ALLOCATEDRIPE NCCwhois.ripe.netLink
90.0.0.0/8RIPE NCC2005-06ALLOCATEDRIPE NCCwhois.ripe.netLink
91.0.0.0/8RIPE NCC2005-06ALLOCATEDRIPE NCCwhois.ripe.netLink
92.0.0.0/8RIPE NCC2007-03ALLOCATEDRIPE NCCwhois.ripe.netLink
93.0.0.0/8RIPE NCC2007-03ALLOCATEDRIPE NCCwhois.ripe.netLink
94.0.0.0/8RIPE NCC2007-07ALLOCATEDRIPE NCCwhois.ripe.netLink
95.0.0.0/8RIPE NCC2007-07ALLOCATEDRIPE NCCwhois.ripe.netLink
96.0.0.0/8ARIN2006-10ALLOCATEDARINwhois.arin.netLink
97.0.0.0/8ARIN2006-10ALLOCATEDARINwhois.arin.netLink
98.0.0.0/8ARIN2006-10ALLOCATEDARINwhois.arin.netLink
99.0.0.0/8ARIN2006-10ALLOCATEDARINwhois.arin.netLink
100.0.0.0/8ARIN2010-11ALLOCATEDARINwhois.arin.netLink
101.0.0.0/8APNIC2010-08ALLOCATEDAPNICwhois.apnic.netLink
102.0.0.0/8AFRINIC2011-02ALLOCATEDAFRINICwhois.afrinic.netLink
103.0.0.0/8APNIC2011-02ALLOCATEDAPNICwhois.apnic.netLink
104.0.0.0/8ARIN2011-02ALLOCATEDARINwhois.arin.netLink
105.0.0.0/8AFRINIC2010-11ALLOCATEDAFRINICwhois.afrinic.netLink
106.0.0.0/8APNIC2011-01ALLOCATEDAPNICwhois.apnic.netLink
107.0.0.0/8ARIN2010-02ALLOCATEDARINwhois.arin.netLink
108.0.0.0/8ARIN2008-12ALLOCATEDARINwhois.arin.netLink
109.0.0.0/8RIPE NCC2009-01ALLOCATEDRIPE NCCwhois.ripe.netLink
110.0.0.0/8APNIC2008-11ALLOCATEDAPNICwhois.apnic.netLink
111.0.0.0/8APNIC2008-11ALLOCATEDAPNICwhois.apnic.netLink
112.0.0.0/8APNIC2008-05ALLOCATEDAPNICwhois.apnic.netLink
113.0.0.0/8APNIC2008-05ALLOCATEDAPNICwhois.apnic.netLink
114.0.0.0/8APNIC2007-10ALLOCATEDAPNICwhois.apnic.netLink
115.0.0.0/8APNIC2007-10ALLOCATEDAPNICwhois.apnic.netLink
116.0.0.0/8APNIC2007-01ALLOCATEDAPNICwhois.apnic.netLink
117.0.0.0/8APNIC2007-01ALLOCATEDAPNICwhois.apnic.netLink
118.0.0.0/8APNIC2007-01ALLOCATEDAPNICwhois.apnic.netLink
119.0.0.0/8APNIC2007-01ALLOCATEDAPNICwhois.apnic.netLink
120.0.0.0/8APNIC2007-01ALLOCATEDAPNICwhois.apnic.netLink
121.0.0.0/8APNIC2006-01ALLOCATEDAPNICwhois.apnic.netLink
122.0.0.0/8APNIC2006-01ALLOCATEDAPNICwhois.apnic.netLink
123.0.0.0/8APNIC2006-01ALLOCATEDAPNICwhois.apnic.netLink
124.0.0.0/8APNIC2005-01ALLOCATEDAPNICwhois.apnic.netLink
125.0.0.0/8APNIC2005-01ALLOCATEDAPNICwhois.apnic.netLink
126.0.0.0/8APNIC2005-01ALLOCATEDAPNICwhois.apnic.netLink
127.0.0.0/8IANA - Loopback1981-09RESERVEDIANA--
128.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
129.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
130.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
131.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
132.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
133.0.0.0/8Administered by APNIC1997-03LEGACYAPNICwhois.apnic.netLink
134.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
135.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
136.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
137.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
138.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
139.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
140.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
141.0.0.0/8Administered by RIPE NCC1993-05LEGACYRIPE NCCwhois.ripe.netLink
142.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
143.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
144.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
145.0.0.0/8Administered by RIPE NCC1993-05LEGACYRIPE NCCwhois.ripe.netLink
146.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
147.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
148.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
149.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
150.0.0.0/8Administered by APNIC1993-05LEGACYAPNICwhois.apnic.netLink
151.0.0.0/8Administered by RIPE NCC1993-05LEGACYRIPE NCCwhois.ripe.netLink
152.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
153.0.0.0/8Administered by APNIC1993-05LEGACYAPNICwhois.apnic.netLink
154.0.0.0/8Administered by AFRINIC1993-05LEGACYAFRINICwhois.afrinic.netLink
155.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
156.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
157.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
158.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
159.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
160.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
161.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
162.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
163.0.0.0/8Administered by APNIC1993-05LEGACYAPNICwhois.apnic.netLink
164.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
165.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
166.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
167.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
168.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
169.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
170.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
171.0.0.0/8Administered by APNIC1993-05LEGACYAPNICwhois.apnic.netLink
172.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
173.0.0.0/8ARIN2008-02ALLOCATEDARINwhois.arin.netLink
174.0.0.0/8ARIN2008-02ALLOCATEDARINwhois.arin.netLink
175.0.0.0/8APNIC2009-08ALLOCATEDAPNICwhois.apnic.netLink
176.0.0.0/8RIPE NCC2010-05ALLOCATEDRIPE NCCwhois.ripe.netLink
177.0.0.0/8LACNIC2010-06ALLOCATEDLACNICwhois.lacnic.netLink
178.0.0.0/8RIPE NCC2009-01ALLOCATEDRIPE NCCwhois.ripe.netLink
179.0.0.0/8LACNIC2011-02ALLOCATEDLACNICwhois.lacnic.netLink
180.0.0.0/8APNIC2009-04ALLOCATEDAPNICwhois.apnic.netLink
181.0.0.0/8LACNIC2010-06ALLOCATEDLACNICwhois.lacnic.netLink
182.0.0.0/8APNIC2009-08ALLOCATEDAPNICwhois.apnic.netLink
183.0.0.0/8APNIC2009-04ALLOCATEDAPNICwhois.apnic.netLink
184.0.0.0/8ARIN2008-12ALLOCATEDARINwhois.arin.netLink
185.0.0.0/8RIPE NCC2011-02ALLOCATEDRIPE NCCwhois.ripe.netLink
186.0.0.0/8LACNIC2007-09ALLOCATEDLACNICwhois.lacnic.netLink
187.0.0.0/8LACNIC2007-09ALLOCATEDLACNICwhois.lacnic.netLink
188.0.0.0/8Administered by RIPE NCC1993-05LEGACYRIPE NCCwhois.ripe.netLink
189.0.0.0/8LACNIC1995-06ALLOCATEDLACNICwhois.lacnic.netLink
190.0.0.0/8LACNIC1995-06ALLOCATEDLACNICwhois.lacnic.netLink
191.0.0.0/8Administered by LACNIC1993-05LEGACYLACNICwhois.lacnic.netLink
192.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
193.0.0.0/8RIPE NCC1993-05ALLOCATEDRIPE NCCwhois.ripe.netLink
194.0.0.0/8RIPE NCC1993-05ALLOCATEDRIPE NCCwhois.ripe.netLink
195.0.0.0/8RIPE NCC1993-05ALLOCATEDRIPE NCCwhois.ripe.netLink
196.0.0.0/8Administered by AFRINIC1993-05LEGACYAFRINICwhois.afrinic.netLink
197.0.0.0/8AFRINIC2008-10ALLOCATEDAFRINICwhois.afrinic.netLink
198.0.0.0/8Administered by ARIN1993-05LEGACYARINwhois.arin.netLink
199.0.0.0/8ARIN1993-05ALLOCATEDARINwhois.arin.netLink
200.0.0.0/8LACNIC2002-11ALLOCATEDLACNICwhois.lacnic.netLink
201.0.0.0/8LACNIC2003-04ALLOCATEDLACNICwhois.lacnic.netLink
202.0.0.0/8APNIC1993-05ALLOCATEDAPNICwhois.apnic.netLink
203.0.0.0/8APNIC1993-05ALLOCATEDAPNICwhois.apnic.netLink
204.0.0.0/8ARIN1994-03ALLOCATEDARINwhois.arin.netLink
205.0.0.0/8ARIN1994-03ALLOCATEDARINwhois.arin.netLink
206.0.0.0/8ARIN1995-04ALLOCATEDARINwhois.arin.netLink
207.0.0.0/8ARIN1995-11ALLOCATEDARINwhois.arin.netLink
208.0.0.0/8ARIN1996-04ALLOCATEDARINwhois.arin.netLink
209.0.0.0/8ARIN1996-06ALLOCATEDARINwhois.arin.netLink
210.0.0.0/8APNIC1996-06ALLOCATEDAPNICwhois.apnic.netLink
211.0.0.0/8APNIC1996-06ALLOCATEDAPNICwhois.apnic.netLink
212.0.0.0/8RIPE NCC1997-10ALLOCATEDRIPE NCCwhois.ripe.netLink
213.0.0.0/8RIPE NCC1993-10ALLOCATEDRIPE NCCwhois.ripe.netLink
214.0.0.0/8US-DOD1998-03LEGACYARINwhois.arin.netLink
215.0.0.0/8US-DOD1998-03LEGACYARINwhois.arin.netLink
216.0.0.0/8ARIN1998-04ALLOCATEDARINwhois.arin.netLink
217.0.0.0/8RIPE NCC2000-06ALLOCATEDRIPE NCCwhois.ripe.netLink
218.0.0.0/8APNIC2000-12ALLOCATEDAPNICwhois.apnic.netLink
219.0.0.0/8APNIC2001-09ALLOCATEDAPNICwhois.apnic.netLink
220.0.0.0/8APNIC2001-12ALLOCATEDAPNICwhois.apnic.netLink
221.0.0.0/8APNIC2002-07ALLOCATEDAPNICwhois.apnic.netLink
222.0.0.0/8APNIC2003-02ALLOCATEDAPNICwhois.apnic.netLink
223.0.0.0/8APNIC2010-04ALLOCATEDAPNICwhois.apnic.netLink
224.0.0.0/8Multicast1981-09RESERVEDIANA--
225.0.0.0/8Multicast1981-09RESERVEDIANA--
226.0.0.0/8Multicast1981-09RESERVEDIANA--
227.0.0.0/8Multicast1981-09RESERVEDIANA--
228.0.0.0/8Multicast1981-09RESERVEDIANA--
229.0.0.0/8Multicast1981-09RESERVEDIANA--
230.0.0.0/8Multicast1981-09RESERVEDIANA--
231.0.0.0/8Multicast1981-09RESERVEDIANA--
232.0.0.0/8Multicast1981-09RESERVEDIANA--
233.0.0.0/8Multicast1981-09RESERVEDIANA--
234.0.0.0/8Multicast1981-09RESERVEDIANA--
235.0.0.0/8Multicast1981-09RESERVEDIANA--
236.0.0.0/8Multicast1981-09RESERVEDIANA--
237.0.0.0/8Multicast1981-09RESERVEDIANA--
238.0.0.0/8Multicast1981-09RESERVEDIANA--
239.0.0.0/8Multicast1981-09RESERVEDIANA--
240.0.0.0/8Future use1981-09RESERVEDIANA--
241.0.0.0/8Future use1981-09RESERVEDIANA--
242.0.0.0/8Future use1981-09RESERVEDIANA--
243.0.0.0/8Future use1981-09RESERVEDIANA--
244.0.0.0/8Future use1981-09RESERVEDIANA--
245.0.0.0/8Future use1981-09RESERVEDIANA--
246.0.0.0/8Future use1981-09RESERVEDIANA--
247.0.0.0/8Future use1981-09RESERVEDIANA--
248.0.0.0/8Future use1981-09RESERVEDIANA--
249.0.0.0/8Future use1981-09RESERVEDIANA--
250.0.0.0/8Future use1981-09RESERVEDIANA--
251.0.0.0/8Future use1981-09RESERVEDIANA--
252.0.0.0/8Future use1981-09RESERVEDIANA--
253.0.0.0/8Future use1981-09RESERVEDIANA--
254.0.0.0/8Future use1981-09RESERVEDIANA--
255.0.0.0/8Future use1981-09RESERVEDIANA--

About IPv4 Address Space

The IPv4 address space consists of 256 /8 blocks (0.0.0.0/8 through 255.0.0.0/8), providing approximately 4.3 billion addresses. IANA (Internet Assigned Numbers Authority) manages the allocation of these address blocks to Regional Internet Registries (RIRs) and reserves some blocks for special purposes.

Regional Internet Registries (RIRs)

Five RIRs manage IPv4 address allocation globally:

  • • ARIN: American Registry for Internet Numbers - North America
  • • RIPE NCC: Réseaux IP Européens - Europe, Middle East, Central Asia
  • • APNIC: Asia-Pacific Network Information Centre - Asia-Pacific
  • • LACNIC: Latin America and Caribbean Network Information Centre
  • • AFRINIC: African Network Information Centre - Africa

Address Block Status

  • • ALLOCATED: Delegated entirely to a specific RIR for distribution
  • • RESERVED: Designated for specific non-global purposes (private, loopback, multicast, etc.)
  • • LEGACY: Allocated before RIRs existed, now administered by RIRs with historical assignments

Special Purpose Addresses

Several address blocks are reserved for specific non-global purposes:

  • • 0.0.0.0/8: Self-identification ("this network")
  • • 10.0.0.0/8: Private-Use Networks (RFC 1918)
  • • 127.0.0.0/8: Loopback addresses (localhost)
  • • 169.254.0.0/16: Link-Local addresses (APIPA)
  • • 172.16.0.0/12: Private-Use Networks (RFC 1918)
  • • 192.0.0.0/24: IETF Protocol Assignments
  • • 192.0.2.0/24: Documentation (TEST-NET-1, RFC 5737)
  • • 192.168.0.0/16: Private-Use Networks (RFC 1918)
  • • 198.18.0.0/15: Benchmarking (RFC 2544)
  • • 198.51.100.0/24: Documentation (TEST-NET-2, RFC 5737)
  • • 203.0.113.0/24: Documentation (TEST-NET-3, RFC 5737)
  • • 224.0.0.0/4: Multicast addresses (Class D)
  • • 240.0.0.0/4: Reserved for future use (Class E)
  • • 255.255.255.255/32: Limited broadcast address

IPv4 Address Exhaustion

IANA's pool of unallocated IPv4 addresses was exhausted in 2011. Most RIRs have also exhausted their pools, leading to increased IPv6 adoption and IPv4 address trading markets.

For the most current and complete information, visit IANA IPv4 Address Space Registry

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