Overview of services running on Port 53 TCP.
~7.99 Million IP addresses observed from May to December 2012
To get raw lists of the data go to Download. For an explanation of what this data is and how it was obtained, see Paper.

Servicename	Product	Count	Percent
domain	ISC BIND	3448177	43.168
domain	dnsmasq	1739294	21.774
domain		1252128	15.675
domain	OpenDNS Updater	709874	8.887
domain	Microsoft DNS	426347	5.337
socks4	Connection rejected or failed; connections possibly ok	174552	2.185
no match	-/-	94625	1.185
domain	MikroTik RouterOS named or OpenDNS Updater	47625	0.596
domain	PowerDNS	36839	0.461
domain	NLNet Labs Unbound	13388	0.168
domain	pdnsd	12699	0.159
domain	Nortel Contivity firewall DNS	9298	0.116
domain	Fortinet FortiGate named	5695	0.071
secure-socket	CA Secure Socket Adapter	2841	0.036
chat	AIM or ICQ server	2340	0.029
ssh	OpenSSH	2269	0.028
socks4	Connection failed; ident required	1977	0.025
domain	v6rev	1783	0.022
socks4	Connection ok	867	0.011
socks4	Connection failed; username required	764	0.01
http	Microsoft IIS httpd	592	0.007
http		503	0.006
http	lighttpd	397	0.005
domain	MyDNS	368	0.005
domain	D-Link DIR-300 WAP named	367	0.005
http	Microsoft HTTPAPI httpd	178	0.002
domain	MaraDNS	146	0.002
domain	Incognito DNS Commander	144	0.002
vtun	Vtun Virtual Tunnel	132	0.002
ssh		123	0.002
openvpn	OpenVPN	110	0.001
ssh	Dropbear sshd	93	0.001
telnet		65	0.001
ftp	Microsoft ftpd	65	0.001
vnc	VNC	58	0.001
ftp		56	0.001
http	Boa HTTPd	49	0.001
mongodb	MongoDB	48	0.001
ftp	Serv-U ftpd	43	0.001
domain	OzymanDNS DNS tunnel	41	0.001
ssh	Bitvise WinSSHD	38	0.0
http	nginx	38	0.0
ftp	FileZilla ftpd	34	0.0
telnet	Linux telnetd	33	0.0
smtp		30	0.0
ftp	ProFTPD	27	0.0
telnet	Allied Telesis x900-series switch telnetd	26	0.0
smtp	Postfix smtpd	26	0.0
smtp	Microsoft Exchange smtpd	26	0.0
mysql	MySQL	25	0.0
smtp	Microsoft ESMTP	24	0.0
arcserve	ARCserve Discovery	24	0.0
ssh	SCS sshd	18	0.0
ftp	Pure-FTPd	18	0.0
ssl	TLS	16	0.0
ftp	vsftpd	16	0.0
directconnect	Direct Connect P2P	16	0.0
audioworks	AudioWorks sound server	16	0.0
socks5		14	0.0
minecraft	Minecraft game server	14	0.0
vnc	RealVNC Enterprise	13	0.0
smtp	Alt-N MDaemon mail server	11	0.0
domain	Edimax BR-6104K router named	11	0.0
vnc	RealVNC Personal	10	0.0