TOP-DOMAINCurrently, worldwide domain registration is managed by (ICANN) Internet Corporation for Assigned Names and Numbers, is a non-profit entity, subordinated to the United States Government, responsible for allocating Internet Protocol address space (IPv4 and IPv6), assigning protocol identifiers, administering the generic top-level domain name system (gTLDs) and country code (ccTLDs), as well as the root server system management functions.

Based in Marina del Rey, ICANN was created on September 18, 1998 to coordinate some tasks originally performed under contract with the US government, through the Internet Assigned Numbers Authority (IANA) and other entities. It has been linked to the US Department of Commerce since the beginning of its activities.

in Brazil the Information and Coordination Center of Ponto BR (NIC.br) is responsible for controlling the records ending in .br, with the Reigstro.br website being responsible for registering domains in the country.

Below are listed the world's largest domain registrars (.com, .net, etc.).

World's Largest Domain Registrars 
rank Company Parents percentage Total Domains
1 GO DADDY United States 31.830% 24,273,545
2 ENOM United States 8.040% 6,131,394
3 TUCOWS Canada 6.910% 5,269,321
4 NETWORK SOLUTIONS United States 6.644% 5,066,505
5 SCHLUND+PARTNER Germany 4.916% 3,749,168
6 MELBOURNE IT Australia 3.191% 2,433,477
7 WILD WEST DOMAINS United States 2.757% 2,102,383
8 REGISTER.COM United States 2.187% 1,667,693
9 RESELLERCLUB.COM India 1.737% 1,324,848
10 MONIKER United States 1.536% 1,171,672
11 KEY-SYSTEMS Germany 1.389% 1,058,962
12 FASTDOMAIN.COM United States 1.350% 1,029,691
13 onamae.com Japan 1.113% 848,573
14 OVH France 0.985% 750,897
15 XINNET.COM China 0.972% 741,605
16 STRATO AG Germany 0.967% 737,299
17 FABULOUS.COM Australia 0.924% 704,825
18 DOTSTER United States 0.922% 703,371
19 PSI-USA Germany 0.891% 679,387
20 ASCIO Denmark 0.879% 670,570
21 DOMAINDISCOVER United States 0.752% 573,291
22 NET.CN China 0.744% 567,260
23 DIRECTNIC United States 0.723% 551,228
24 MARKMONITOR United States 0.658% 501,784
25 GANDI France 0.612% 466,717
26 ONLINENIC United States 0.590% 450,164
27 NAME.COM United States 0.580% 442,024
28 DREAMHOST United States 0.535% 408,143
29 CORPORATE DOMAINS United States 0.519% 395,477
30 REGISTER.IT Italy 0.444% 338,502
31 JOKER.COM Germany 0.423% 322,575
32 NAMESDIRECT United States 0.399% 304,157
33 DOMAINPEOPLE Canada 0.368% 280,256
34 NICLINE Spain 0.348% 265,156
35 DO TRADE United States 0.326% 248,546
36 SRSPLUS United States 0.305% 232,896
37 CORE NIC Switzerland 0.290% 221,077
38 NAMES4EVER United States 0.277% 211,361
39 BIZCN.COM China 0.271% 206,928
40 INTERNETWIRE.NET Germany 0.259% 197,365
41 BASICFUSION.COM United States 0.259% 197,336
42 35.COM China 0.249% 190,211
43 WEBNIC Malaysia 0.238% 181,878
44 DYNADOT United States 0.236% 180,172
45 NAMESECURE United States 0.187% 142,464
46 ACTIVE 24 ASA Norway 0.183% 139,334
47 EPAG Domainservices Germany 0.174% 132,764
48 ANTAGUS.DE Germany 0.170% 129,770
49 DNS.COM.CN China 0.167% 127,212
50 UNITED-DOMAINS.DE Germany 0.166% 126,868
51 123-REG.CO.UK United Kingdom 0.164% 125,033
52 ENAME.COM China 0.160% 121,684
53 NAMEBAY Monaco 0.160% 121,645
54 UK2GROUP.COM Gibraltar 0.137% 104,374
55 GKG United States 0.136% 103,956
56 BOOKMYNAME France 0.133% 101,167
57 DOMAINSITE.COM United States 0.131% 100,204
58 NAME7 Korea 0.129% 98,215
59 1API.DE Germany 0.122% 93,353
60 DOMAINMONSTER.COM United Kingdom 0.119% 91,122

  Largest Domain Registrars in Brazil

rank Company Parents percentage Total Domains
82 LOCAWEB Brazil 0.082% 62,469
114 UOLHOST Brazil 0.046% 34,780
206 IGCOMPANIES Brazil 0.010% 7,769
227 BR NAME Brazil 0.007% 5,690
294 HOSTNET Brazil 0.003% 2,070

Source: webhosting.info (Data – 10/10/2013)