[134298] in North American Network Operators' Group
2010 IPv4 (and IPv6) Address Use Report
daemon@ATHENA.MIT.EDU (Iljitsch van Beijnum)
Tue Jan 4 06:29:57 2011
From: Iljitsch van Beijnum <iljitsch@muada.com>
Date: Tue, 4 Jan 2011 12:29:48 +0100
To: NANOG list <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
[ (Non-cross)posted to NANOG, PPML, RIPE IPv6 wg, Dutch IPv6 TF. ]
On the web:
IPv4: http://www.bgpexpert.com/addrspace2010.php
IPv6: http://www.bgpexpert.com/addrspace-ipv6-2010.php
The IPv4 one is included below:
2010 IPv4 Address Use Report
As of January 1, 2011, the number of unused IPv4 addresses is 495.66 =
million. Exactly a year earlier, the number of available addresses was =
721.06 million. So we collectively used up 225.4 million addresses in =
2010.
35 of the 256 the /8s that make up the IPv4 address space have the =
status "reserved". 0 and 127 have special meaning and can't be used for =
normal purposes. 224 - 239 are used for multicast and 240 - 255 are =
"reserved for future use". With only about two years worth of IPv4 =
addresses remaining on the shelves, it would seem that that future is =
here now, but unfortunately, pretty much all operating systems balk at =
using a "reserved" address. So unreserving those addresses means =
upgrading EVERY system connected to the Internet. If we're going to do =
that, we may as well skip those reserved IPv4 addresses and upgrade to =
IPv6. Last but not least, there's block 10, which is the largest of the =
three address blocks set aside for private use. The others, =
172.16.0.0/12 and 192.168.0.0/16, don't show up as reserved, but are =
obviously not available for regular use.
This makes the total number of usable IPv4 addresses is (256 - 35) * =
2^24 - 2^20 - 2^16 =3D 3706.65 million addresses. The "IANA global pool" =
consists of 7 /8s (117.44 million) are still unused (unallocated): 39/8, =
102/8, 103/8, 104/8, 106/8, 179/8 and 185/8. But there's also a lot of =
unused space hiding in the "allocated" and "legacy" categories. Each RIR =
publishes a list of address blocks further delegated to ISPs or end =
users every day on their FTP servers. If we add up all those blocks, =
this comes out to 3210.99 million addresses. So the total number of =
usable-but-unused IPv4 addresses is 3706.65 - 3210.99 =3D 495.66 =
million.
Going back to the IANA global pool, these are the changes over the past =
year:
Delegated Blocks +/- 2010
to/status
AfriNIC 3 +1
APNIC 42 +8
ARIN 35 +4
LACNIC 8 +2
RIPE NCC 34 +4
LEGACY 92
UNALLOCATED 7 -19
There is an agreement between IANA and the RIRs that each RIR will get =
one of the last five /8s. APNIC has been getting two /8s every three =
months like clockwork in 2010. If this continues, they'll be getting =
numbers 7 and 6 later this month, and then the final distribution will =
look like this:
Delegated Blocks +/- 2010
to/status
AfriNIC 4
APNIC 45
ARIN 36
LACNIC 9
RIPE NCC 35
LEGACY 92
UNALLOCATED -
At this point, it becomes very interesting what the status of the legacy =
space is, exactly. The legacy blocks are each "administered" by one of =
the RIRs, but does that mean that that RIR is free to further delegate =
that space to ISPs and end users? There are 146.92 million unused =
addresses in legacy space, including 16.65 million returned by Interop a =
few months ago. This is the used versus unused address space =
administered by each RIR:
Legacy Allocated
total unused total unused
AfriNIC 33.55 24.85 50.33 27.06
APNIC 100.66 22.32 704.64 44.38
ARIN 654.31 60.55 587.20 56.21
LACNIC - - 134.22 37.39
RIPE NCC 67.11 5.77 570.43 67.38
IANA 671.09 16.65 - -
AfriNIC used up 8.95 million addresses last year. So their current =
unused allocated space is good for another three years (if nothing =
changes) and their final /8 is worth another almost two years. If they =
get to use their legacy space, that buys them another 2.5 years. So =
unless IPv4 address use <em>really</em> takes off in Africa, AfriNIC =
will be handing out addresses for at least three or four years.
APNIC is at the opposite end of the spectrum, using up no less than =
126.22 million new IPv4 addresses last year. Even if they get to use the =
legacy space they administer on top of three of the last seven /8s and, =
it's hard to see how APNIC can avoid having to tell people "no" before =
the year is out. However, there is a caveat: in the 2010 APNIC records, =
there is 6.65 million addresses worth of space that isn't in the 2011 =
records. Part of this is address space returned to APNIC. In other =
cases, an address block delegated in a previous year expands or shrinks =
retroactively. Depending on what the underlying reason for these changes =
is, the actual rate at which APNIC and the other RIRs are giving out =
address space may be different from what it seems to be at first glance.
ARIN, LACNIC, and the RIPE NCC used up 54.55, 17.29, and 75.45 million =
addresses, respectively, in 2010. However, ARIN saw 27.24 million =
addresses returned, including the 16.65 million from Interop, which is =
administered in the ARIN records even though the IANA list doesn't =
reflect this. For AfriNIC, LACNIC and the RIPE NCC the numbers of =
addresses that came back were 0.31, 0.22, and 22.62 million, =
respectively.
With respect to running out of addresses, it's important to realize that =
the Pareto principle (the 80/20 rule) applies: out of the 7686 address =
blocks given out last year, only 392 (5 percent) were blocks larger than =
100,000 addresses, but those were responsible for 82 percent of the =
address <em>space</em> given out. Even when the RIRs are no longer able =
to give out those large blocks, they may still be able to fulfill the =
requests for address blocks smaller than 10,000 addresses. Last year, =
6425 such blocks were given out, totaling 14.03 million addresses. It =
really only takes a single address to be in the content business; it's =
the ISPs that need a continuous supply of new addresses to connect new =
customers. So the address shortages looming beyond the summer will hit =
ISPs and their broadband/mobile customers first and foremost, and the =
content industry to a much lesser degree.
The top 15 IPv4 address holding countries:
2011-01-01 2010-01-01 Increase Country
1 - US 1519.53 M 1495.13 M 1.6% United States
2 - CN 277.64 M 232.45 M 19.4% China
3 - JP 186.82 M 177.15 M 5.5% Japan
4 - EU 151.80 M 149.48 M 1.6% Multi-country in =
Europe
5 (6) KR 103.50 M 77.77 M 33.1% Korea
6 (5) DE 91.61 M 86.51 M 5.9% Germany
7 (9) GB 82.25 M 74.18 M 10.9% United Kingdom
8 - CA 79.53 M 76.96 M 3.3% Canada
9 - FR 79.29 M 75.54 M 5.0% France =20
10 - AU 49.10 M 39.77 M 23.5% Australia
11 - BR 40.24 M 33.95 M 18.5% Brazil
12 - IT 37.14 M 33.50 M 10.9% Italy
13 - RU 34.66 M 28.47 M 21.7% Russia
14 - TW 31.93 M 27.10 M 17.8% Taiwan
15 (19) IN 28.70 M 19.42 M 47.8% India
Because the US holds so much space, the increase of 25 million addresses =
seems small, but that's still more than 10% of the address space given =
out in 2010. China's growth is slowing down a little at 45 million =
addresses last year compared to 50 million in 2009. But other countries =
in Asia are picking up the slack and then some: Korea keeps using up =
large amounts of address space, and India is now also picking up the =
pace. The US now has 47.3% of the address space in use, down from 50.1% =
a year ago. The other countries in the top 15 collectively hold 39.7%, =
up from 38%. That leaves 13% for the rest of the world, up from 12%.
Note that I slightly changed the way addresses are counted: previously, =
all the legacy blocks that didn't have an RIR listed were assumed to be =
used 100%. But with the return of most of the Interop block this is no =
longer the case: although ARIN isn't listed as administering the 45/8 =
block, they actually are and only have 45.0.0.0/15 listed as in use.=
