Security + Ports

20 & 21

FTP
File Transfer Protocol

22

SSH (SFTP)
Secure Shell (Secure File Transport Protocol)

23

TELNET

25

SMTP
Simple Mail Transfer Protocol

49

TACACS
Terminal Access Controller Access-Control System

53

DNS
Domain Name Service

67 & 68

DHCP
Dynamic Host Configuration Protocol

69

TFTP
Trivial File Transfer Protocol

80

HTTP
Hypertext Transfer Protocol

110

POP3
Post Office Protocol v3

137-139

NetBIOS

143

IMAP4
Internet Message Access Protocol v4

161 & 162

SNMP
Simple Network Management Protocol

389

LDAP
Lightweight Directory Access Protocol

443

HTTPS/ SSL
Hypertext Transport Protocol over Secure Sockets Layer

500 & 4500

IKE
Internet Key Exchange

636

Sec LDAP
Secure Lightweight Directory Access Protocol

990

FTPS (control)
File Transfer Protocol Secure (SSL)

989

FTPS (Data)
File Transfer Protocol Secure (SSL)

1293

IPSec
Internet Protocol Security

1701 UDP

L2TP
Layer 2 Tunneling Protocol

1723 TCP

PPTP
Point-to-Point Tunneling Protocol

1812

RADIUS
Remote Authentication Dial-In Service

3389

RDP
Remote Desktop Protocol