[v6ops] Buying and selling IPv4 addresses and the size of the global BGP routing table -- Re: draft-vf-v6ops-ipv6-deployment

[Lencse Gábor <[e-mail]>]

30/03/2021 18:01 keltezéssel, STARK, BARBARA H írta:

> Wireline ISPs who historically provided public IPv4 addresses to their customers
> generally still have those IPv4 addresses (unless they chose to sell them). Some

Yes, it seems to be logical from the viewpoint of both parties to sell 
IPv4 addresses that are no more needed and to buy IPv4 addresses if they 
are needed.

However, it has a consequence for all the other operators, who do not 
take part in it. I have just recently met some statistics from the 
regular report of IIJ, Japan. I hope that the two tables will remain 
readable:

*Table 1: Number of Routes by Prefix Length for Full IPv4 Routes***

**

*Date***

	

*/8***

	

*/9***

	

*/10***

	

*/11***

	

*/12***

	

*/13***

	

*/14***

	

*/15***

	

*/16***

	

*/17***

	

*/18***

	

*/19***

	

*/20***

	

*/21***

	

*/22***

	

*/23***

	

*/24***

	

*Total***

Sep. 2011

	

19

	

12

	

27

	

81

	

233

	

457

	

794

	

1407

	

11909

	

5907

	

9885

	

19515

	

26476

	

26588

	

35515

	

34061

	

190276

	

363162

Sep. 2012

	

19

	

14

	

29

	

84

	

236

	

471

	

838

	

1526

	

12334

	

6349

	

10710

	

20927

	

30049

	

31793

	

42007

	

39517

	

219343

	

416246

Sep. 2013

	

16

	

11

	

30

	

93

	

250

	

480

	

903

	

1613

	

12748

	

6652

	

10971

	

22588

	

32202

	

34900

	

48915

	

42440

	

244822

	

459634

Sep. 2014

	

16

	

12

	

30

	

90

	

261

	

500

	

983

	

1702

	

13009

	

7013

	

11659

	

24527

	

35175

	

37560

	

54065

	

47372

	

268660

	

502634

Sep. 2015

	

18

	

13

	

36

	

96

	

261

	

500

	

999

	

1731

	

12863

	

7190

	

12317

	

25485

	

35904

	

38572

	

60900

	

52904

	

301381

	

551170

Sep. 2016

	

16

	

13

	

36

	

101

	

267

	

515

	

1050

	

1767

	

13106

	

7782

	

12917

	

25229

	

38459

	

40066

	

67270

	

58965

	

335884

	

603443

Sep. 2017

	

15

	

13

	

36

	

104

	

284

	

552

	

1047

	

1861

	

13391

	

7619

	

13385

	

24672

	

38704

	

41630

	

78779

	

64549

	

367474

	

654115

Sep. 2018

	

14

	

11

	

36

	

99

	

292

	

567

	

1094

	

1891

	

13325

	

7906

	

13771

	

25307

	

39408

	

45578

	

88476

	

72030

	

400488

	

710293

Sep. 2019

	

10

	

11

	

37

	

98

	

288

	

573

	

1142

	

1914

	

13243

	

7999

	

13730

	

25531

	

40128

	

47248

	

95983

	

77581

	

438926

	

764442

Sep. 2020

	

9

	

11

	

39

	

100

	

286

	

576

	

1172

	

1932

	

13438

	

8251

	

14003

	

25800

	

40821

	

49108

	

101799

	

84773

	

473899

	

816017

**

*Table 2: Total Number of Unique IPv4 Addresses in Full IPv4 Routes***

**

*Date***

	

*No. of IPv4 addresses***

Sep. 2011

	

2,470,856,448

Sep. 2012

	

2,588,775,936

Sep. 2013

	

2,638,256,384

Sep. 2014

	

2,705,751,040

Sep. 2015

	

2,791,345,920

Sep. 2016

	

2,824,538,880

Sep. 2017

	

2,852,547,328

Sep. 2018

	

2,855,087,616

Sep. 2019

	

2,834,175,488

Sep. 2020

	

2,850,284,544


Source: https://www.iij.ad.jp/en/dev/iir/pdf/iir_vol49_report_EN.pdf

While the number of unique IPv6 addresses has grown from 2.47M to 2.85M 
by only 15%, the number of routes has grown from 363k to 816k by 125% in 
the last 9 years. If you observe the details, you can see that the 
number of /8 prefixes decreased from 19 to 9, while the number of /22 
prefixes increased from 35k to 101k.

I expect that buying and selling of IPv4 addresses will likely intensify 
this tendency, as larger prefixes will be divided into smaller ones, and 
the size of global BGP routing table will grow significantly.

The need for buying more RAM or even replacing routers may be a driving 
force from CGN towards IPv4aaS.

Gábor