What is a Port?
When an application
wants to utilize the Internet connection it must do so in a way that the data
it is sending or requesting will remain separate from data that is destined
other applications. This is important as different applications requires
different types of information, for example Outlook Express would get confused
if it tried to process data that was in fact web page information and similarly
if Internet Explorer was trying to display wed pages based on email related
data then it would have a similar problem. To overcome this, applications
create and utilize what are known as ports.
Common
Ports
20
FTP data (File Transfer Protocol)
21
FTP (File Transfer Protocol)
22
SSH (Secure Shell)
23
Telnet
25
SMTP (Send Mail Transfer Protocol)
43
whois
53
DNS (Domain Name Service)
68
DHCP (Dynamic Host Control Protocol)
79
Finger
80
HTTP (Hypertext Transfer Protocol)
110
POP3 (Post Office Protocol, version 3)
115
SFTP (Secure File Transfer Protocol)
119
NNTP (Network New Transfer Protocol)
123
NTP (Network Time Protocol)
137
Net BIOS-ns
138
NetBIOS-dgm
139
Net BIOS
143
IMAP (Internet Message Access Protocol)
161
SNMP (Simple Network Management Protocol)
194
IRC (Internet Relay Chat)
220
IMAP3 (Internet Message Access Protocol 3)
389
LDAP (Lightweight Directory Access Protocol)
443
SSL (Secure Socket Layer)
445
SMB (Net BIOS over TCP)
666
Doom
993
SIMAP (Secure Internet Message Access Protocol)
995
SPOP (Secure Post Office Protocol)
Ports
between 1024 and 29151 are known as the Registered Ports. Basically, programs
are supposed to register their use of these ports and thereby try to be careful
and avoid stomping on each other. Here are some common ports and their
programs.
1243
Sub Seven (Trojan - security risk!)
1352
Lotus Notes
1433
Microsoft SQL Server
1494
Citrix ICA Protocol
1521
Oracle SQL
1604
Citrix ICA / Microsoft Terminal Server
2049
NFS (Network File System)
3306
mySQL
4000
ICQ
5010
Yahoo! Messenger
5190
AOL Instant Messenger
5632
PCAnywhere
5800
VNC
5900
VNC
6000
X Windowing System
6699
Napster
6776
Sub Seven (Trojan - security risk!)
7070
Real Server / QuickTime
7778
Unreal
8080
HTTP
26000
Quake
27010
Half-Life
27960
Quake III
31337
BackOrifice (Trojan - security risk!)
For
a complete list of Trojans & their ports, see http://www.simovits.com/nyheter9902.html
======================