[ipv6-wg] 2008 IPv4 Address Use Report

[ (Non-cross)posted to IETF discussions, NANOG, PPML, RIPE IPv6 wg,  
Dutch IPv6 TF. Web version for the monospace font impaired and with  
some links:
http://www.bgpexpert.com/addrspace2008.php ]

2008 IPv4 Address Use Report

As of January first, 2009, the number of unused IPv4 addresses is  
925.58 million. On January 1, 2008, it was 1122.85 million. So in  
2008, 197.27 million addresses were used up. With 3706.65 million  
usable addresses, this means that 75.3% of the available IPv4  
addresses are in some kind of use, up from 69.7% a year ago. So the  
depletion of the IPv4 address reserves is continuing in much the same  
way as in previous years:

Date         Addresses free   Used up
2006-01-01      1468.61 M
2007-01-01      1300.65 M    167.96 M
2008-01-01      1122.85 M    177.80 M (with return of 16.78 M to IANA)
2009-01-01       925.58 M    197.27 M

These figures are derived from from the Internet Assigned Numbers  
Authority's IPv4 Global Unicast Address Assignments page and the  
records published on the FTP servers of the five Regional Internet  
Registries (RIRs): AfriNIC, which gives out address space in Africa,  
APNIC (Asia-Pacific region), ARIN (North America), LACNIC (Latin  
American and the Caribbean) and the RIPE NCC (Europe, the former  
Soviet Union and the Middle East).

The IANA list shows the status of all 256 blocks of 16777216 addresses  
identified by the first 8-bit number in the IPv4 address. (Note that  
the file is in a somewhat different format than in previous years.)  
The RIR data indicates how much address space the RIRs have delegated  
to internet service providers (and sometimes end-users).

Delegated    Blocks  +/- 2008   Addresses      Used     Available
to/status                                 (in millions)

AfriNIC         2                 33.55        9.18      24.37
APNIC          30       +4       503.32      454.36      48.96
ARIN           31       +4       520.09      446.06      74.03
LACNIC          6                100.66       68.88      31.78
RIPE NCC       26                436.21      423.65      12.56
LEGACY         92       +1      1543.50     1363.29     180.21
UNALLOCATED    34       -9       570.43                 570.43

Totals        221               3707.76     2765.42     942.34

The difference between the 942.34 million free addresses here and  
925.58 million earlier is explained by the fact that the 43.0.0.0/8  
legacy block shows up as delegated in the IANA list, but not in the  
APNIC delegation records. In previous years, 7.0.0.0/8 didn't show up  
in the IANA records but it did in the ARIN records. This has now been  
fixed, hence the increase in legacy delegations. No legacy blocks were  
returned to IANA in 2008.

The total number of available addresses is slightly higher than the  
previously mentioned figure at 3707.76 million because the table above  
includes 172.16.0.0/12 and 192.168.0.0/16, which are set aside for  
private use.

Networks 0.0.0.0/8 and 127.0.0.0/8 aren't usable because of special  
uses and 10.0.0.0/8 is also set aside for private use. 224 - 239 are  
multicast addresses, and 240 - 255 is class E, which is "reserved" for  
future use. If the class E space could be used, it would increase the  
available address space by 268 million addresses. The past two years,  
this has been a topic of hot debate in the IETF and elsewhere. The  
problem is that almost all operating systems need modification to be  
able to use class E addresses, and a good part of the installed base  
of devices connected to the internet must be considered unupgradable.

The 2781.07 million addresses currently in use aren't very evenly  
distributed over the countries in the world. The current top 15 is:

              2009-01-01  2008-01-01  increase  Country

1     -     US   1458.21 M   1408.15 M     4%     United States
2    (3)    CN    181.80 M    135.31 M    34%     China
3    (2)    JP    151.56 M    141.47 M     7%     Japan
4     -     EU    120.29 M    120.35 M     0%     Multi-country in  
Europe
5     -     GB     86.31 M     83.50 M     3%     United Kingdom
6    (7)    DE     81.75 M     72.46 M    13%     Germany
7    (6)    CA     74.49 M     73.20 M     2%     Canada
8     -     FR     68.04 M     67.79 M     0%     France
9     -     KR     66.82 M     58.86 M    14%     Korea
10    -     AU     36.26 M     33.43 M     8%     Australia
11   (12)   BR     29.75 M     23.46 M    27%     Brazil
12   (11)   IT     29.64 M     24.04 M    23%     Italy
13   (16)   TW     24.01 M     19.83 M    21%     Taiwan
14   (18)   RU     23.18 M     17.01 M    36%     Russia
15   (14)   ES     21.67 M     20.42 M     6%     Spain

In 2008, the United States was again the biggest user of new address  
space with no less than 50 million addresses added to the 1.4 billion  
they already had at the beginning of the year. China is a close second  
with 46.50 million new addresses. There is no clear trend in the  
growth percentages. A few countries like France and the UK show very  
modest growth, while other countries with a large installed base like  
Germany and Korea saw double digit growth percentages. And in addition  
to China, Brazil, Taiwan and Russia, but also Italy, are catching up.

The US now holds 52.4% of the IPv4 address space in use. The total for  
the top 15 excluding the US is 35.8%. The rest of the world gets the  
remaining 327.23 million addresses, or 11.8%.

The size of address blocks given out was increasing until 2005, but  
now shows a downturn. The table below shows the number of delegations  
for a certain range of block sizes (equal or higher than the first,  
lower than the second value).

              2002    2003    2004    2005    2006    2007    2008

< 1000           547     745    1022    1309    1507    1830    1896
1000 - 8000      897    1009    1516    1891    2265    2839    3235
8000 - 64k       822    1014    1100    1039    1192    1015    1129
64k - 500k       163     215     404     309     419     395     410
500k - 2M         29      46      61      60      57      62      82
 > 2M               5       6       7      18      17      24      18

In millions of addresses:

              2002    2003    2004    2005    2006    2007    2008

< 1000          0.18    0.25    0.35    0.44    0.51    0.63    0.65
1000 - 8000     3.23    3.45    4.49    5.07    5.83    6.93    7.75
8000 - 64k     11.35   14.00   15.99   15.46   18.01   15.67   17.40
64k - 500k     20.28   25.51   42.01   34.23   50.86   50.83   52.58
500k - 2M      21.30   31.98   44.63   41.63   46.69   45.50   57.41
 > 2M           12.58   12.58   20.97   68.62   52.43   67.37   54.00

The growth in the smallest and largest categories has been curtailed,  
but this growth now seems to happen in the second smallest and second  
largest categories, so the total effect isn't all that different, as  
indicated by the number of addresses given out per request/delegation:

Year    Blocks    Addresses (M)   Average block size

2000      2794            78.35                28043
2001      2824            88.95                31497
2002      2463            68.93                27985
2003      3035            87.77                28921
2004      4110           128.45                31252
2005      4626           165.45                35765
2006      5457           174.32                31945
2007      6165           186.92                30320
2008      6770           189.79                28035

(The numbers of addresses given out are lower here because ARIN often  
attributes the delegation of new addresses to a previous year, this  
view doesn't correct for that.)