PORTS NUMBERS : Just as the physical address (MAC address) and the logical address (IP address) helps to route the traffic to a particular machine on a network, it is the port that identifies which service on the machine this traffic is destined to.

A port on a specific computer is called a socket. It can be open, closed, listening or have a connection established.

20 - FTP - data transfer

21 - FTP - control (command)

22 - SSH

23 - Telnet

25 - SMTP

37 - Time

43 - WHOIS

42 - WINS

53 - DNS

67 - BOOTp

68 - DHCP

69 - TFTP

79 - FINGER

80 - HTTP (WWW)

88 - Kerberose

101 - HOSTNAME

110 - POP3

111 - rpcbind

119 - NNTP

123 - NTP (Time)

137 - NetBios (nmbd)

139 - NetBios ( Samba)

143 - IMAP/Dovecot

161 - SNMP

180 - RIS

220 - IMAP3

389 - LDAP

443 - HTTPs

500 - Internet Key Exchange (IKE), IPSec

520 - RIP

546 - DHCPV6 client

547 - DHCPV6 server

554 - rtsp(Real Time Stream Protocol, Audio/Video)

631 - Printing (ipp)

744 - Flexlm

901 - SWAT

953 - rndc

993 - IMAPSecure

995 - POPs

999 - POP over SSL/TLS

2049 - NFS

2082 - CPANEL

2083 - CPANEL Secure SSL/TLS

2086 - CPANEL WHM

2087 - CPANEL WHM Secure/SSL

2095 - CPANEL Webmail

2096 - CPANEL Webmail Secure/SSL

2222 - Direct Admin Control Panel

2401 - CVSP server

3268 - AD Global Catalog

3269 - AD Global Catalog over SSL

3306 - MySQL Server

3389 - Terminal services (rdp-remote desktop protocol)

4643 - Virtusso Power Panel

(6000 - X11

6063)

8443 - Pleask Control Panel

9999 - Urchin

10000- Webmin Control Panel

21018- Skype