ASN and Network Prefixes for TLD Nameservers (2021-10)

On Monday, October 4, 2021, Facebook had BGP advertisements removed for several hours for two networks within the same ASN. These networks were to their four DNS nameserver IPs. This included IPv6 too. This effectively disabled their websites and related services (due to lame delegations resulting in SERVFAILs).

What are the best practices related to this? RFC 2182 says "Secondary servers must be placed at both topologically and geographically dispersed locations on the Internet." NIST requirements say "All authoritative name servers for a zone must be located on different network segments." And IANA's requirements for its authoritative name servers says they must be in at least two topologically-separate origin autonomous systems in the BGP routing table. While it is common for a single organization to have different networks under the same AS number, what is the best practice?

The following table is for all the TLDs to show the count of different ASNs for each IPv4 nameserver (from root server delegations) for the TLD and the count of network prefixes for each too. Sixteen TLDs have IPv4 nameservers from only a single ASN (like Facebook). (For IPv6, there are 48 TLDs with a single ASN for all nameservers.) The most common is two different ASNs and the highest is ten.

Eight TLDs have only a single ASN and single network too for IPv4. (For IPv6, there are 32 TLDs with a single ASN and single network prefix for all nameservers.) The most common is four different networks and again ten networks is the highest.

This table may be sorted by clicking on the headers. (Other tables for most popular ASNs are below too.)

TLD ASN Count (IPv4) Network Count (IPv4)
aaa 3 6
aarp 4 4
abarth 2 4
abb 4 4
abbott 2 4
abbvie 4 8
abc 4 4
able 3 6
abogado 4 8
abudhabi 2 4
ac 2 4
academy 2 6
accenture 3 4
accountant 2 6
accountants 2 6
aco 2 3
actor 2 6
ad 4 4
adac 4 4
ads 2 5
adult 2 4
ae 3 4
aeg 3 4
aero 2 5
aetna 3 6
af 2 3
afamilycompany 3 4
afl 2 4
africa 3 3
ag 2 6
agakhan 2 4
agency 2 6
ai 3 4
aig 3 6
airbus 4 4
airforce 2 6
airtel 3 4
akdn 2 4
al 4 4
alfaromeo 2 4
alibaba 2 4
alipay 2 4
allfinanz 4 4
allstate 2 4
ally 2 4
alsace 3 3
alstom 3 3
am 4 4
amazon 4 8
americanexpress 3 6
americanfamily 3 4
amex 2 6
amfam 3 4
amica 3 6
amsterdam 3 3
analytics 3 6
android 2 5
anquan 2 4
anz 2 4
ao 3 3
aol 3 4
apartments 2 6
app 2 5
apple 2 4
aq 3 3
aquarelle 3 3
ar 6 6
arab 2 4
aramco 2 6
archi 2 4
army 2 6
arpa 10 10
art 4 4
arte 3 4
as 3 6
asda 4 4
asia 2 6
associates 2 6
at 6 8
athleta 3 6
attorney 2 6
au 6 9
auction 2 5
audi 2 4
audible 4 8
audio 4 4
auspost 2 4
author 4 8
auto 2 2
autos 4 4
avianca 2 4
aw 4 4
aws 4 8
ax 1 2
axa 3 6
az 2 2
azure 4 4
ba 2 2
baby 4 4
baidu 3 6
banamex 3 6
bananarepublic 3 6
band 2 6
bank 2 6
bar 4 4
barcelona 2 2
barclaycard 3 4
barclays 2 4
barefoot 4 4
bargains 2 6
baseball 3 6
basketball 2 4
bauhaus 2 2
bayern 4 8
bb 2 4
bbc 4 8
bbt 3 4
bbva 4 8
bcg 2 4
bcn 2 2
bd 2 3
be 3 6
beats 2 4
beauty 4 4
beer 4 8
bentley 3 8
berlin 2 3
best 4 4
bestbuy 2 4
bet 2 4
bf 4 4
bg 3 6
bh 4 4
bharti 3 4
bi 4 5
bible 3 6
bid 3 6
bike 2 6
bing 3 4
bingo 2 6
bio 2 4
biz 2 6
bj 6 7
black 2 4
blackfriday 4 4
blockbuster 2 4
blog 4 4
bloomberg 4 4
blue 2 4
bm 2 6
bms 4 4
bmw 4 4
bn 4 4
bnpparibas 2 4
bo 4 4
boats 4 4
boehringer 2 4
bofa 3 4
bom 5 5
bond 4 4
boo 2 5
book 4 8
booking 3 6
bosch 3 4
bostik 3 3
boston 4 8
bot 4 8
boutique 2 6
box 4 4
br 5 5
bradesco 4 8
bridgestone 4 4
broadway 4 8
broker 2 6
brother 2 4
brussels 3 6
bs 2 2
bt 5 5
budapest 4 8
bugatti 2 4
build 4 4
builders 2 6
business 2 6
buy 4 8
buzz 3 6
bv 2 3
bw 3 4
by 5 5
bz 2 6
bzh 3 3
ca 4 4
cab 2 6
cafe 2 6
cal 2 5
call 4 8
calvinklein 3 6
cam 4 4
camera 2 6
camp 2 6
cancerresearch 2 4
canon 2 4
capetown 3 3
capital 2 6
capitalone 3 4
car 4 4
caravan 3 6
cards 2 6
care 2 6
career 4 8
careers 2 6
cars 4 4
casa 5 8
case 4 4
cash 2 6
casino 2 6
cat 6 6
catering 2 6
catholic 2 4
cba 2 4
cbn 3 6
cbre 2 6
cbs 2 4
cc 4 4
cd 2 3
center 2 6
ceo 4 4
cern 2 4
cf 2 4
cfa 3 4
cfd 4 4
cg 3 3
ch 5 6
chanel 3 4
channel 2 5
charity 2 6
chase 3 6
chat 2 6
cheap 2 6
chintai 3 6
christmas 4 4
chrome 2 5
church 2 6
ci 5 5
cipriani 2 4
circle 4 8
cisco 2 6
citadel 2 6
citi 3 6
citic 3 6
city 2 6
cityeats 4 4
ck 2 2
cl 7 7
claims 2 6
cleaning 2 6
click 4 4
clinic 2 6
clinique 2 4
clothing 2 6
cloud 2 4
club 3 6
clubmed 3 4
cm 5 7
cn 5 7
co 2 6
coach 2 6
codes 2 6
coffee 2 6
college 4 4
cologne 3 3
com 3 10
comcast 4 8
commbank 2 4
community 2 6
company 2 6
compare 2 4
computer 2 6
comsec 3 4
condos 2 6
construction 2 6
consulting 2 6
contact 2 6
contractors 2 6
cooking 4 8
cookingchannel 3 4
cool 2 6
coop 4 4
corsica 3 3
country 4 4
coupon 3 6
coupons 2 5
courses 2 4
cpa 2 4
cr 6 6
credit 2 6
creditcard 2 6
creditunion 3 4
cricket 2 6
crown 3 4
crs 3 4
cruise 2 4
cruises 2 6
csc 4 4
cu 5 5
cuisinella 2 4
cv 4 4
cw 4 5
cx 2 3
cy 5 5
cymru 4 8
cyou 4 4
cz 2 4
dabur 2 4
dad 2 5
dance 2 6
data 2 4
date 3 6
dating 2 6
datsun 2 4
day 2 5
dclk 2 5
dds 4 8
de 5 6
deal 4 8
dealer 4 4
deals 2 6
degree 2 6
delivery 2 6
dell 3 6
deloitte 4 4
delta 2 4
democrat 2 6
dental 2 6
dentist 2 6
desi 4 4
design 4 4
dev 2 5
dhl 4 4
diamonds 2 6
diet 4 4
digital 2 6
direct 2 6
directory 2 6
discount 2 6
discover 3 6
dish 2 4
diy 3 4
dj 2 3
dk 7 7
dm 7 8
dnp 2 4
do 5 6
docs 2 5
doctor 2 6
dog 2 6
domains 2 6
dot 2 4
download 3 6
drive 2 5
dtv 2 4
dubai 2 4
duck 4 4
dunlop 2 4
dupont 3 6
durban 3 3
dvag 4 4
dvr 2 4
dz 6 6
earth 3 6
eat 2 5
ec 3 3
eco 2 4
edeka 2 4
edu 3 10
education 2 6
ee 5 5
eg 3 3
email 2 6
emerck 2 4
energy 2 6
engineer 2 6
engineering 2 6
enterprises 2 6
epson 2 4
equipment 2 6
er 2 2
ericsson 4 4
erni 2 2
es 3 5
esq 2 5
estate 2 6
et 1 1
etisalat 4 4
eu 5 5
eurovision 2 2
eus 3 3
events 2 6
exchange 2 6
expert 2 6
exposed 2 6
express 2 6
extraspace 2 4
fage 2 4
fail 2 6
fairwinds 4 4
faith 3 6
family 2 6
fan 2 6
fans 4 4
farm 2 6
farmers 3 6
fashion 4 8
fast 4 8
fedex 2 4
feedback 4 4
ferrari 2 4
ferrero 3 6
fi 9 10
fiat 2 4
fidelity 4 4
fido 2 4
film 2 4
final 5 5
finance 2 6
financial 2 6
fire 4 8
firestone 2 4
firmdale 2 2
fish 2 6
fishing 4 8
fit 5 8
fitness 2 6
fj 2 3
fk 2 2
flickr 3 6
flights 2 6
flir 3 6
florist 2 6
flowers 4 4
fly 2 5
fm 5 6
fo 4 4
foo 2 5
food 3 4
foodnetwork 4 4
football 2 6
ford 3 6
forex 2 6
forsale 2 6
forum 4 4
foundation 2 6
fox 2 6
fr 4 4
free 4 8
fresenius 4 4
frl 4 4
frogans 2 4
frontdoor 3 4
frontier 3 6
ftr 3 6
fujitsu 2 4
fun 5 5
fund 2 6
furniture 2 6
futbol 2 6
fyi 2 6
ga 2 4
gal 2 2
gallery 2 6
gallo 3 4
gallup 2 4
game 4 4
games 2 6
gap 3 6
garden 4 8
gay 4 4
gb 2 2
gbiz 2 5
gd 4 4
gdn 2 3
ge 4 5
gea 2 3
gent 4 4
genting 4 4
george 3 4
gf 1 2
gg 3 6
ggee 2 4
gh 2 3
gi 2 6
gift 4 4
gifts 2 6
gives 2 5
giving 2 4
gl 3 4
glade 4 4
glass 2 6
gle 2 5
global 2 4
globo 5 5
gm 2 2
gmail 2 5
gmbh 2 6
gmo 2 4
gmx 2 2
gn 3 3
godaddy 2 4
gold 2 6
goldpoint 2 4
golf 2 6
goo 3 4
goodyear 2 4
goog 2 5
google 2 5
gop 4 8
got 4 8
gov 3 4
gp 4 4
gq 2 4
gr 5 5
grainger 3 6
graphics 2 6
gratis 2 6
green 2 4
gripe 2 6
grocery 4 4
group 2 6
gs 2 3
gt 6 6
gu 3 3
guardian 4 4
gucci 4 8
guge 2 5
guide 2 6
guitars 4 4
guru 2 6
gw 3 3
gy 2 2
hair 4 4
hamburg 2 3
hangout 2 5
haus 2 6
hbo 3 6
hdfc 2 4
hdfcbank 2 4
health 2 6
healthcare 2 6
help 4 4
helsinki 2 4
here 2 5
hermes 2 4
hgtv 3 4
hiphop 4 4
hisamitsu 2 4
hitachi 3 4
hiv 4 4
hk 6 7
hkt 2 4
hm 2 2
hn 3 3
hockey 2 6
holdings 2 6
holiday 2 6
homedepot 2 4
homegoods 3 6
homes 4 4
homesense 3 6
honda 2 4
horse 4 8
hospital 2 6
host 5 5
hosting 4 4
hot 4 8
hoteles 2 6
hotels 3 6
hotmail 4 4
house 2 6
how 2 5
hr 3 3
hsbc 3 6
ht 3 3
hu 6 7
hughes 2 4
hyatt 3 6
hyundai 3 4
ibm 2 4
icbc 2 4
ice 4 4
icu 4 4
id 1 4
ie 5 6
ieee 3 6
ifm 2 2
ikano 2 3
il 6 6
im 2 4
imamat 2 4
imdb 5 8
immo 2 6
immobilien 2 6
in 2 6
inc 4 4
industries 2 6
infiniti 4 4
info 2 6
ing 2 5
ink 4 4
institute 2 6
insurance 3 6
insure 2 6
int 5 6
international 2 6
intuit 3 6
investments 2 6
io 2 4
ipiranga 3 6
iq 3 3
ir 4 5
irish 2 6
is 5 5
ismaili 2 4
ist 2 4
istanbul 2 4
it 4 5
itau 2 6
itv 2 4
jaguar 4 4
java 3 4
jcb 2 4
je 3 5
jeep 2 4
jetzt 2 6
jewelry 2 6
jio 2 4
jll 2 4
jm 4 4
jmp 2 6
jnj 3 6
jo 3 4
jobs 4 8
joburg 3 3
jot 4 8
joy 4 8
jp 8 8
jpmorgan 3 6
jprs 4 4
juegos 4 4
juniper 3 4
kaufen 2 6
kddi 3 4
ke 5 5
kerryhotels 3 4
kerrylogistics 3 4
kerryproperties 3 4
kfh 4 4
kg 2 2
kh 3 3
ki 1 1
kia 2 4
kim 2 4
kinder 3 6
kindle 5 8
kitchen 2 6
kiwi 2 2
km 2 2
kn 2 3
koeln 3 3
komatsu 3 4
kosher 2 4
kp 1 1
kpmg 3 6
kpn 4 4
kr 6 6
krd 2 4
kred 4 4
kuokgroup 4 4
kw 5 5
ky 4 4
kyoto 2 4
kz 2 2
la 2 2
lacaixa 2 2
lamborghini 2 4
lamer 2 4
lancaster 3 3
lancia 2 4
land 2 6
landrover 3 4
lanxess 3 6
lasalle 2 4
lat 4 6
latino 2 4
latrobe 2 4
law 4 8
lawyer 2 6
lb 6 6
lc 2 6
lds 2 4
lease 2 6
leclerc 3 3
lefrak 3 4
legal 2 6
lego 3 4
lexus 4 4
lgbt 2 4
li 5 6
lidl 4 4
life 2 6
lifeinsurance 3 6
lifestyle 3 4
lighting 2 6
like 4 8
lilly 3 6
limited 2 6
limo 2 6
lincoln 2 6
linde 4 4
link 4 4
lipsy 4 4
live 2 6
living 4 4
lixil 3 4
lk 7 8
llc 2 4
llp 4 4
loan 3 6
loans 2 6
locker 2 4
locus 4 8
loft 3 6
lol 4 4
london 4 4
lotte 3 4
lotto 2 4
love 4 4
lpl 4 4
lplfinancial 4 4
lr 3 3
ls 3 4
lt 3 6
ltd 2 6
ltda 2 4
lu 5 6
lundbeck 3 4
luxe 4 8
luxury 4 4
lv 5 7
ly 4 5
ma 5 5
macys 3 4
madrid 2 2
maif 3 4
maison 2 6
makeup 4 4
man 2 2
management 2 6
mango 2 2
map 2 5
market 2 6
marketing 2 6
markets 2 6
marriott 2 4
marshalls 3 6
maserati 2 4
mattel 3 6
mba 2 6
mc 3 3
mckinsey 2 4
md 3 4
me 2 5
med 4 8
media 2 6
meet 2 5
melbourne 2 4
meme 2 5
memorial 2 6
men 2 4
menu 2 4
merckmsd 4 4
mg 4 5
mh 2 2
miami 4 8
microsoft 3 4
mil 1 6
mini 4 4
mint 3 6
mit 2 4
mitsubishi 3 4
mk 4 4
ml 2 4
mlb 3 6
mls 2 2
mm 3 4
mma 3 3
mn 6 10
mo 3 4
mobi 2 6
mobile 2 4
moda 2 6
moe 3 6
moi 4 8
mom 4 4
monash 2 4
money 2 6
monster 4 4
mormon 2 4
mortgage 2 6
moscow 3 4
moto 3 6
motorcycles 4 4
mov 2 5
movie 2 6
mp 2 2
mq 1 2
mr 5 5
ms 1 1
msd 3 4
mt 3 4
mtn 4 8
mtr 2 4
mu 4 4
museum 3 3
mutual 3 6
mv 2 3
mw 6 7
mx 4 6
my 6 6
mz 4 4
na 4 4
nab 3 4
nagoya 3 4
name 3 4
natura 5 5
navy 2 6
nba 2 6
nc 3 3
ne 2 2
nec 2 4
net 4 10
netbank 2 4
netflix 3 6
network 2 6
neustar 2 6
new 2 5
news 2 6
next 3 4
nextdirect 3 4
nexus 2 5
nf 2 3
nfl 3 6
ng 3 3
ngo 2 6
nhk 2 4
ni 4 5
nico 3 4
nike 3 6
nikon 4 4
ninja 2 6
nissan 2 4
nissay 4 4
nl 3 3
no 5 6
nokia 2 4
northwesternmutual 2 6
norton 3 4
now 4 8
nowruz 3 4
nowtv 2 4
np 5 5
nr 3 3
nra 2 4
nrw 2 2
ntt 3 3
nu 5 6
nyc 2 6
nz 6 7
obi 4 4
observer 2 6
off 4 4
office 3 6
okinawa 4 4
olayan 2 4
olayangroup 2 4
oldnavy 3 6
ollo 2 4
om 3 6
omega 4 4
one 2 4
ong 2 6
onl 2 4
online 5 5
ooo 4 4
open 3 6
oracle 3 4
orange 3 4
org 2 6
organic 2 4
origins 2 4
osaka 3 6
otsuka 2 4
ott 2 4
ovh 3 3
pa 4 4
page 2 5
panasonic 3 4
paris 3 3
pars 3 4
partners 2 6
parts 2 6
party 3 6
passagens 3 6
pay 4 8
pccw 2 4
pe 4 4
pet 2 4
pf 1 1
pfizer 2 6
pg 3 4
ph 4 4
pharmacy 4 8
phd 2 5
philips 2 4
phone 2 4
photo 4 4
photography 2 6
photos 2 6
physio 2 4
pics 4 4
pictet 4 4
pictures 2 6
pid 4 4
pin 4 8
ping 3 6
pink 2 4
pioneer 2 4
pizza 2 6
pk 4 4
pl 9 9
place 2 6
play 2 5
playstation 2 4
plumbing 2 6
plus 2 6
pm 4 4
pn 4 5
pnc 2 4
pohl 4 4
poker 2 4
politie 3 3
porn 2 4
post 1 4
pr 4 8
pramerica 3 6
praxi 2 6
press 5 5
prime 4 8
pro 2 6
prod 2 5
productions 2 6
prof 2 5
progressive 2 4
promo 2 4
properties 2 6
property 4 4
protection 4 4
pru 3 6
prudential 3 6
ps 7 7
pt 7 8
pub 2 6
pw 5 6
pwc 2 4
py 5 5
qa 5 7
qpon 4 4
quebec 2 2
quest 4 4
qvc 3 6
racing 3 6
radio 2 2
raid 3 4
re 4 4
read 4 8
realestate 4 8
realtor 4 8
realty 2 6
recipes 2 6
red 2 4
redstone 2 4
redumbrella 2 4
rehab 2 6
reise 2 6
reisen 2 6
reit 4 4
reliance 2 4
ren 3 6
rent 4 4
rentals 2 6
repair 2 6
report 2 6
republican 2 6
rest 4 4
restaurant 2 6
review 3 6
reviews 2 6
rexroth 3 4
rich 2 4
richardli 2 4
ricoh 3 4
ril 2 4
rio 5 5
rip 2 6
ro 4 5
rocher 2 6
rocks 2 6
rodeo 4 8
rogers 2 4
room 4 8
rs 5 5
rsvp 2 5
ru 2 5
rugby 3 4
ruhr 2 2
run 2 6
rw 4 4
rwe 4 4
ryukyu 3 4
sa 5 7
saarland 4 4
safe 5 8
safety 2 6
sakura 3 3
sale 2 6
salon 2 6
samsclub 3 4
samsung 4 4
sandvik 2 4
sandvikcoromant 3 4
sanofi 3 4
sap 2 2
sarl 2 6
sas 3 6
save 4 8
saxo 2 4
sb 2 3
sbi 2 4
sbs 4 4
sc 3 7
sca 3 4
scb 4 4
schaeffler 2 3
schmidt 3 4
scholarships 2 4
school 2 6
schule 2 6
schwarz 4 4
science 3 6
scjohnson 4 4
scot 2 2
sd 5 6
se 8 10
search 2 5
seat 2 2
secure 4 8
security 4 4
seek 2 4
select 2 4
sener 4 4
services 2 6
ses 3 4
seven 2 4
sew 2 4
sex 2 4
sexy 4 4
sfr 4 4
sg 5 5
sh 2 4
shangrila 3 4
sharp 2 4
shaw 2 4
shell 4 4
shia 3 4
shiksha 2 4
shoes 2 6
shop 2 4
shopping 2 6
shouji 2 4
show 2 6
showtime 2 4
si 7 7
silk 4 8
sina 2 4
singles 2 5
site 5 5
sj 2 3
sk 5 7
ski 2 4
skin 4 4
sky 3 4
skype 3 6
sl 2 2
sling 2 4
sm 3 3
smart 4 4
smile 4 8
sn 4 4
sncf 3 3
so 2 2
soccer 2 6
social 2 6
softbank 3 4
software 2 6
sohu 3 6
solar 2 6
solutions 2 6
song 2 6
sony 2 4
soy 2 5
spa 2 4
space 5 5
sport 3 3
spot 4 8
sr 1 1
srl 2 4
ss 3 3
st 3 4
stada 2 4
staples 3 6
star 2 4
statebank 2 4
statefarm 3 6
stc 4 4
stcgroup 4 4
stockholm 2 4
storage 4 4
store 5 5
stream 3 6
studio 2 6
study 2 4
style 2 6
su 2 5
sucks 2 4
supplies 2 6
supply 2 6
support 2 6
surf 4 8
surgery 2 6
suzuki 3 4
sv 7 8
swatch 4 4
swiftcover 3 6
swiss 3 3
sx 2 2
sy 3 3
sydney 3 4
systems 2 6
sz 3 3
tab 2 4
taipei 3 6
talk 4 8
taobao 3 6
target 2 6
tatamotors 4 4
tatar 2 5
tattoo 4 4
tax 2 6
taxi 2 6
tc 5 5
tci 3 4
td 3 4
tdk 3 6
team 2 6
tech 5 5
technology 2 6
tel 4 8
temasek 2 4
tennis 2 6
teva 3 6
tf 4 4
tg 5 6
th 5 5
thd 2 4
theater 2 6
theatre 4 4
tiaa 4 4
tickets 4 4
tienda 2 6
tiffany 4 4
tips 2 5
tires 2 6
tirol 3 3
tj 4 4
tjmaxx 3 6
tjx 3 6
tk 2 4
tkmaxx 3 6
tl 2 3
tm 4 7
tmall 3 6
tn 5 5
to 4 7
today 2 6
tokyo 2 4
tools 2 6
top 3 6
toray 2 4
toshiba 2 4
total 3 3
tours 2 5
town 2 6
toyota 2 4
toys 2 6
tr 5 5
trade 3 6
trading 2 6
training 2 6
travel 2 6
travelchannel 3 4
travelers 2 4
travelersinsurance 2 4
trust 4 4
trv 2 4
tt 4 4
tube 3 6
tui 4 4
tunes 4 8
tushu 4 8
tv 3 4
tvs 2 4
tw 8 10
tz 6 6
ua 4 4
ubank 4 4
ubs 4 4
ug 5 5
uk 4 8
unicom 3 6
university 2 6
uno 5 5
uol 5 5
ups 2 4
us 2 6
uy 6 7
uz 6 7
va 4 4
vacations 2 6
vana 4 4
vanguard 4 4
vc 2 6
ve 4 5
vegas 2 4
ventures 2 6
verisign 3 4
versicherung 2 3
vet 2 6
vg 4 4
vi 2 2
viajes 2 6
video 2 6
vig 2 4
viking 2 4
villas 2 6
vin 2 6
vip 5 8
virgin 4 8
visa 3 4
vision 2 6
viva 4 4
vivo 2 6
vlaanderen 3 6
vn 6 6
vodka 4 8
volkswagen 2 4
volvo 4 4
vote 2 4
voting 2 4
voto 2 4
voyage 2 6
vu 2 4
vuelos 3 6
wales 4 8
walmart 3 4
walter 3 4
wang 3 6
wanggou 4 8
watch 2 6
watches 2 4
weather 3 6
weatherchannel 3 6
webcam 3 6
weber 3 4
website 4 4
wed 5 8
wedding 4 8
weibo 2 4
weir 3 4
wf 4 4
whoswho 3 3
wien 3 3
wiki 4 4
williamhill 2 6
win 3 6
windows 3 4
wine 2 6
winners 3 6
wme 4 4
wolterskluwer 2 4
woodside 2 4
work 4 8
works 2 6
world 2 6
wow 4 8
ws 2 4
wtc 3 4
wtf 2 6
xbox 4 4
xerox 3 4
xfinity 4 8
xihuan 1 2
xin 2 4
xn--11b4c3d 3 4
xn--1ck2e1b 2 6
xn--1qqw23a 2 5
xn--2scrj9c 2 6
xn--30rr7y 3 6
xn--3bst00m 3 6
xn--3ds443g 2 4
xn--3e0b707e 6 6
xn--3hcrj9c 2 6
xn--3oq18vl8pn36a 2 4
xn--3pxu8k 3 4
xn--42c2d9a 3 4
xn--45br5cyl 2 6
xn--45brj9c 2 6
xn--45q11c 3 6
xn--4gbrim 2 4
xn--54b7fta0cc 2 3
xn--55qw42g 2 5
xn--55qx5d 2 5
xn--5su34j936bgsg 4 4
xn--5tzm5g 2 4
xn--6frz82g 2 4
xn--6qq986b3xl 2 5
xn--80adxhks 3 4
xn--80ao21a 2 2
xn--80aqecdr1a 3 4
xn--80asehdb 2 2
xn--80aswg 2 2
xn--8y0a063a 3 6
xn--90a3ac 5 5
xn--90ae 3 6
xn--90ais 5 5
xn--9dbq2a 3 4
xn--9et52u 3 6
xn--9krt00a 2 4
xn--b4w605ferd 2 4
xn--bck1b9a5dre4c 2 6
xn--c1avg 2 4
xn--c2br7g 3 4
xn--cck2b3b 2 6
xn--cckwcxetd 4 8
xn--cg4bki 4 4
xn--clchc0ea0b2g2a9gcd 5 5
xn--czr694b 3 6
xn--czrs0t 2 6
xn--czru2d 3 6
xn--d1acj3b 2 5
xn--d1alf 3 3
xn--e1a4c 5 5
xn--eckvdtc9d 2 6
xn--efvy88h 3 6
xn--fct429k 3 6
xn--fhbei 4 4
xn--fiq228c5hs 2 4
xn--fiq64b 3 6
xn--fiqs8s 4 7
xn--fiqz9s 4 7
xn--fjq720a 2 6
xn--flw351e 2 5
xn--fpcrj9c3d 2 6
xn--fzc2c9e2c 6 7
xn--fzys8d69uvgm 2 4
xn--g2xx48c 3 6
xn--gckr3f0f 3 6
xn--gecrj9c 2 6
xn--gk3at1e 3 6
xn--h2breg3eve 2 6
xn--h2brj9c 2 6
xn--h2brj9c8c 2 6
xn--hxt814e 2 5
xn--i1b6b1a6a2e 2 4
xn--imr513n 3 6
xn--io0a7i 2 5
xn--j1aef 3 4
xn--j1amh 3 3
xn--j6w193g 7 8
xn--jlq480n2rg 4 8
xn--jlq61u9w7b 2 4
xn--jvr189m 2 6
xn--kcrx77d1x4a 2 4
xn--kprw13d 6 6
xn--kpry57d 6 6
xn--kput3i 2 4
xn--l1acc 2 2
xn--lgbbat1ad8j 3 3
xn--mgb9awbf 4 6
xn--mgba3a3ejt 2 6
xn--mgba3a4f16a 3 3
xn--mgba7c0bbn0a 2 4
xn--mgbaakc7dvf 4 4
xn--mgbaam7a8h 2 3
xn--mgbab2bd 2 2
xn--mgbah1a3hjkrd 5 5
xn--mgbai9azgqp6j 1 1
xn--mgbayh7gpa 3 4
xn--mgbbh1a 2 6
xn--mgbbh1a71e 2 6
xn--mgbc0a9azcg 4 4
xn--mgbca7dzdo 2 4
xn--mgbcpq6gpa1a 4 4
xn--mgberp4a5d4ar 5 7
xn--mgbgu82a 2 6
xn--mgbi4ecexp 3 4
xn--mgbpl2fh 5 5
xn--mgbt3dhd 3 4
xn--mgbtx2b 1 1
xn--mgbx4cd0ab 6 6
xn--mix891f 3 4
xn--mk1bu44c 4 4
xn--mxtq1m 4 4
xn--ngbc5azd 2 4
xn--ngbe9e0a 4 4
xn--ngbrx 2 4
xn--node 3 5
xn--nqv7f 2 4
xn--nqv7fs00ema 2 4
xn--nyqy26a 2 4
xn--o3cw4h 4 4
xn--ogbpf8fl 3 3
xn--otu796d 3 6
xn--p1acf 3 4
xn--p1ai 2 5
xn--pgbs0dh 5 5
xn--pssy2u 4 4
xn--q7ce6a 4 4
xn--q9jyb4c 2 5
xn--qcka1pmc 2 5
xn--qxa6a 5 5
xn--qxam 4 4
xn--rhqv96g 2 4
xn--rovu88b 3 6
xn--rvc1e0am3e 2 6
xn--s9brj9c 3 6
xn--ses554g 3 6
xn--t60b56a 3 4
xn--tckwe 3 4
xn--tiq49xqyj 2 4
xn--unup4y 2 6
xn--vermgensberater-ctb 4 4
xn--vermgensberatung-pwb 4 4
xn--vhquv 2 6
xn--vuq861b 1 2
xn--w4r85el8fhu5dnra 4 4
xn--w4rs40l 3 4
xn--wgbh1c 3 4
xn--wgbl6a 5 7
xn--xhq521b 2 5
xn--xkc2al3hye2a 6 7
xn--xkc2dl3a5ee0h 2 6
xn--y9a3aq 4 4
xn--yfro4i67o 4 4
xn--ygbi2ammx 3 4
xn--zfr164b 2 5
xxx 2 4
xyz 4 4
yachts 4 4
yahoo 3 4
yamaxun 4 8
yandex 4 4
ye 2 2
yodobashi 3 4
yoga 4 8
yokohama 3 4
you 5 8
youtube 2 5
yt 4 4
yun 2 4
za 3 3
zappos 4 8
zara 2 4
zero 3 6
zip 2 5
zm 2 2
zone 2 6
zuerich 4 4
zw 3 3
TLD ASN Count Network Count

Most Common ASN Networks

For all the TLDs, the fifteen most common ASN network prefix pairs are:

RankCountASNNetwork
1 118 AS42 204.61.216.0/23
2 113 AS60890 185.24.64.0/24
3 113 AS199330 194.169.218.0/24
4 110 AS201304 212.18.248.0/24
5 110 AS201303 212.18.249.0/24
6 106 AS397233 37.209.196.0/24
7 102 AS397235 37.209.194.0/24
8 98 AS397235 37.209.192.0/24
9 94 AS397235 37.209.198.0/24
10 92 AS397235 156.154.158.0/24
11 92 AS397235 156.154.157.0/24
12 92 AS397235 156.154.156.0/24
13 92 AS397235 156.154.145.0/24
14 92 AS397233 156.154.144.0/24
15 92 AS397219 156.154.159.0/24

Most Common ASNs

For all the TLDs, the fifteen most common ASNs are:

RankCountASN
1 1552 AS12041
2 886 AS397235
3 695 AS207266
4 344 AS397231
5 331 AS43519
6 283 AS397233
7 184 AS15169
8 162 AS42
9 157 AS397219
10 148 AS397215
11 142 AS396574
12 113 AS60890
13 113 AS199330
14 110 AS201304
15 110 AS201303

This data was collected via our comprehensive DNS audit suite, which covers over 100 checks based on IETF RFC specifications and best practices, government requirements, and registry guidelines. It has identified hundreds of thousands of mistakes (including lame delegations, protocol mistakes, typos, security issues, and more) from research of Fortune 500, S&P Global 100 Banks, US government, TLDs, and EDU domains. What do you use to check your DNS?