Overview of services running on Port 1720 TCP.
~26 Thousand 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
no match	-/-	7761	28.941
H.323-gatekeeper	GNU Gatekeeper	6277	23.407
irc	Dancer ircd	2883	10.751
H.323/Q.931		2591	9.662
ms-wbt-server	Microsoft NetMeeting Remote Desktop Service	1930	7.197
H.323-gatekeeper	CompTek AquaGateKeeper	1823	6.798
ms-wbt-server	Microsoft Terminal Service	1254	4.676
chat	AIM or ICQ server	1114	4.154
http	WangWnagSimpleServer	213	0.794
http	Microsoft IIS httpd	121	0.451
ssh	OpenSSH	117	0.436
socks5		89	0.332
http	Microsoft HTTPAPI httpd	74	0.276
ssh		56	0.209
http		44	0.164
telnet		38	0.142
vnc	VNC	34	0.127
http	Boa HTTPd	29	0.108
arcserve	ARCserve Discovery	28	0.104
ms-wbt-server-proxy	nmproxy NetMeeting proxy	27	0.101
ftp		20	0.075
nntp	INN nntpd	19	0.071
mysql	MySQL	18	0.067
ftp	Microsoft ftpd	16	0.06
http	nginx	15	0.056
ssh	SCS sshd	13	0.048
vnc	RealVNC Enterprise	11	0.041
minecraft	Minecraft game server	11	0.041
vnc	RealVNC Personal	10	0.037
smtp	Microsoft ESMTP	10	0.037