Number ofIP addresses

Number ofIP links

Number ofASes

Number ofAS links

IPv6IPv4 23,037,154

14,68320,187,579

33,92729,316

1,18377,6102,738

C o p y r i g h t © 2 0 1 2 U C R e g e n t sA l l r i g h t s r e s e r v e d .

A R K H O S T S AARNet, Acreo, AMS-IX, APAN, ARIN, ASTI, CAIDA, Canarie, CENIC, CNRST, Colorado State Univ., DePaul Univ., Evolva

Telecom, FORTH, FunkFeuer, HEANet, Hurricane Electric, Indonesian IPv6 Task Force, Internet Systems Consortium, Iowa State Univ.,

Kantonsschule, KREONet2, Level 3 Communications, Men and Mice, National Research Council Canada, NCAR, NIC Chile, NIC Mexico,

NORDUnet, Northeastern Univ., Public Univ. of Navarra, Purdue Univ., Registro.br, RNP, Simula Research Laboratory, SURFnet, TKK,

TWAREN, UCAD, Univ. Leipzig, Univ. Politècnica de Catalunya, Univ. of Cambridge, Univ. of Hawaii, Univ. Melbourne, Univ. of Napoli, Univ.

of Nevada at Reno, Univ. of Oregon, Univ. of Waikato, Univ. of Washington, Univ. of Zurich, US Army Research Lab

A N A LY S I S T E A M . Bradley Huffaker, kc claffy

S O F T W A R E D E V E L O P M E N T Young Hyun, Matthew Luckie

P O S T E R D E S I G N Justin Cheng

C O O P E R A T I V E A S S O C I A T I O N F O R I N T E R N E T D A T A A N A LY S I S

San Diego Supercomputer Center . University of California, San Diego

9500 Gilman Drive, mc0505 . La Jolla, CA 92093-0505 . 858-534-5000

http://www.caida.org/research/topology/as_core_network/

www.caida .org

digitalenvoy

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Dublin, IE3356(Level 3)3356(Level 3)

174(Cogent)174(Cogent)

6939(Hurricane Electric)6939(Hurricane Electric)

10026(Pacnet)10026(Pacnet)

1299(TeliaNet)1299(TeliaNet)

22773(Cox)22773(Cox)3561(Savvis)3561(Savvis)

6453(TATA)6453(TATA)

7018(AT&T Services)7018(AT&T Services)

3491(Beyond the Network America)3491(Beyond the Network America)

701(MCI Comm)701(MCI Comm)209(Qwest)209(Qwest)1239(U.S. Sprint)1239(U.S. Sprint)

4323(TW Telecom)4323(TW Telecom)

293(ESnet)293(ESnet)3130(RGnet)3130(RGnet)

6461(Abovenet)6461(Abovenet)

3320(Deutsche Telekom)3320(Deutsche Telekom)1200(AMS-IX1)1200(AMS-IX1)6695(DECIX)6695(DECIX)

1273(eTel)1273(eTel)

20485(Transtelecom)20485(Transtelecom)

12389(Rostelecom)12389(Rostelecom)

12956(Telefonica)12956(Telefonica)10310(Yahoo! India)10310(Yahoo! India)

6128(Cablevision)6128(Cablevision)

3216(Vimpelcom)3216(Vimpelcom)

1785(PaeTec)1785(PaeTec)6327(Shaw Comm)6327(Shaw Comm)7922(Comcast Cable)7922(Comcast Cable)

3549(Global Crossing)3549(Global Crossing)

4766(Korea Telecom)4766(Korea Telecom)

9498(Bharti Airtel)9498(Bharti Airtel)

3786(LG Dacom)3786(LG Dacom)

4657(StarHub Internet Exchange)4657(StarHub Internet Exchange)

2516(KDDI)2516(KDDI)

4768(TelstraClear)4768(TelstraClear)3292(TDC)3292(TDC)

2856(BTnet UK)2856(BTnet UK)

7473(SingTel)7473(SingTel)

2497(Internet Initiative Japan)2497(Internet Initiative Japan)

18881(Global Village Telecom)18881(Global Village Telecom)

18101(Reliance Communications)18101(Reliance Communications)

9505(Taiwan Internet Gateway)9505(Taiwan Internet Gateway)

30751(Eurotel)30751(Eurotel)

12741(Netia)12741(Netia)

IPv6

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Rio de Janeiro, BR

London, UKParis, FR

Berlin, DEVienna, ATStockholm, SESofia, BGHelsin

ki, FIPretoria, ZAKiev, UA

Warsaw, PL

Ankara, TR

Tel Aviv, ILMosco

w, RU

AbuDha

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1200(AMS-IX1)1200(AMS-IX1)

6939(Hurricane Electric)6939(Hurricane Electric) 3257(Tinet)3257(Tinet)

3356(Level3)3356(Level3)

11537(Abilene)11537(Abilene)

6695(DECIX)6695(DECIX)

30071(TowardEX)30071(TowardEX)

5459(LINX)5459(LINX)1299(TeliaNet)1299(TeliaNet)

2914(NTT)2914(NTT)174(Cogent)174(Cogent)

6453(TATA)6453(TATA)

20965(GEANT)20965(GEANT)

13030(INIT7)13030(INIT7) 13237(LambdaNet)13237(LambdaNet)

2603(NORDUnet)2603(NORDUnet)1257(TELE2)1257(TELE2)

2152(Cal State University)2152(Cal State University)

4826(Vocus Connect)4826(Vocus Connect)

7473(SingTel)7473(SingTel)

10026(Pacnet)10026(Pacnet)

7539(TANet2)7539(TANet2)

286(KPN)286(KPN)

1273(Cable and Wireless)1273(Cable and Wireless)

1239(U.S. Sprint)1239(U.S. Sprint)

5511(eTel)5511(eTel)

2500(Wide Project)2500(Wide Project)

3549(Global Crossing)3549(Global Crossing)

2828(XO Communications)2828(XO Communications)

38022(REANNZ)38022(REANNZ)

3267(RUNNet)3267(RUNNet)

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Peering OutDegree:

This visualization represents macroscopic snapshots of IPv4 and IPv6 Internet topology samples captured in 2011. The plotting method illustrates both the extensive geographical scope as well as rich interconnectivity of nodes participating in the global Internet routing system. For the IPv4 map, CAIDA collected data from 54 monitors located in 29 countries on 6 continents. Coordinated by our active measurement infrastructure, Archipelago (Ark1), the monitors probed paths toward 207 million /24 networks that cover 93.3% of the routable pre�xes seen in the Route Views2 Border Gateway Protocol (BGP) routing tables on 1 April 2011. For the IPv6 map, CAIDA collected data from 16 IPv6-connected Ark monitors located in 12 countries on 4 continents. This subset of monitors probed paths toward 307,000 IPv6 pre�xes which represent 71.9% of the globally routed IPv6 pre�xes seen in Route Views BGP tables on 1 April 2011. We aggregate this IP-level data to construct IPv4 and IPv6 Internet connectivity graphs at the Autonomous System (AS) level. Each AS approximately corresponds to an Internet Service Provider (ISP). We map each observed IP address to the AS responsible for routing tra�c to it, i.e., to the origin (end-of-path)

AS for the IP pre�x representing the best match for this address in BGP routing tables collected from Route Views. The position of each AS node is plotted in polar coordinates (radius, angle) calculated as follows.

Our IPv6 graph grew from 677 AS nodes in January 2010 to 1,183 nodes in April 2011 (74% growth). Over the same period, the number of ASes in our IPv4 graph grew 14.0% from 28,175 to 29,315. Most ASes grew their observed peering degree in both our IPv4 and IPv6 graphs, although at di�erent rates, which alters their relative degree-based rank over time. In the IPv4 graph Level 3 (AS 3356) remained dominant with the largest observed degree in both 2010 and 2011. The ASes with the second, third, and fourth largest degrees (Cogent's AS 174, Global Crossing's AS 3549, and AT&T's AS 7018) also maintained their previously observed degree rank. While most ASes increased their degree over this period, the �fth most highly connected AS, Sprint's AS

1239, had its degree decline, dropping its rank to tenth. Note that we rank each AS independently; some network providers have topology spread across multiple ASes. A more accurate topology-based ranking of providers would require a validated list of AS ownership by organization, a data set we are still working to compile. The observed IPv6 AS ranking experienced greater change. Hurricane's AS 6939 moved up from third place in 2010 to �rst place in 2011, not surprising given Hurricane's aggressive peering policy. AS 1200 (Amsterdam IX, an exchange point) dropped from �rst to second place. Internet's AS 11537 and Sprint's AS 6175 fell out of the top ten, and Sprint's AS 1299 and Cogent's AS 174 have moved into the top ten. In the case of the two Sprint ASes, 57% of AS 6175's dropped neighbors were never seen as neighbors of AS 1299, while 64% of AS 1299's new neighbors were never seen as neighbors of AS 6175. The prominence of a European exchange point and a U.S. research network in the observable IPv6 topology is a symptom of the immaturity of the IPv6 infrastructure. As IPv6 deployment progresses we expect increasing congruity between IPv4 and IPv6 topologies, a trend re�ected in the increasing presence of the same top-ranked ASes (by degree) in the two peering graphs. This trend also implies increasing congruity in the

In 2010, the top-ranked ASes in the IPv6 graph were mostly divided across North American and European ASes, but in our 2011 topology measurements the balance has shifted toward

North America, as the top-ranked ASes in the IPv4 graph increased their connectivity in the IPv6 graph.

radius = 1 - log outdegree(AS) + 1maximum.outdegree + 1( )

angle = longitude of the AS’s BGP pre�xes in netacq( )

1Ark: http://www.caida.org/projects/ark/2Route Views: http://www.routeviews.org/

Top 10 AS by Degree

2010.04 2011.04date

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6939: Hurricane Electric, Inc.1200: AMS-IX1 Amsterdam IE 6695: DE-CIX, the German IE3257 : Tinet SpAIPv43356 : LEVEL3IPv42914 : NTT America, Inc.IPv43549 : Global Crossing LTD.IPv41299 : TeliaNet Global NtwkIPv45459: London IE Ltd.174 : Cogent/PSIIPv46453: TATA Communications 11537: Internet26175: Sprint

*IE: Internet Exchange

IPv6

2010.04 2011.04date

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3356 LEVEL3174 Cogent/PSI3549 Global Crossing LTD.7018 AT&T701 MCI Communications 1299 TeliaNet Global Ntwk 3257 Tinet SpA 4323 tw telecom holdings2914 NTT America 209 Qwest Comms1239 Sprint

IPv4

CAIDA’S IPv4 & IPv6 AS CoreAS-level INTERNET GRAPH

Archipelago April 2011