File Transfer

Service TCP UDP
FTP 20, 21  
SCP, SFTP 22  
TFTP   69
FTPS (SSL) 443  
SMB 445  

E-mail

Service TCP UDP
SMTP 25  
POP3 110  
IMAP4 143  

Remote Access/Connections

Service TCP UDP
SSH 22  
Telnet 23  
TACACS (+) (Terminal Access Controller Access-Control System) 49  
SSL VPN 443  
ISAKMP (Internet Security Association & Key Management Protocol (VPN))   500
L2TP (Layer 2 Tunneling Protocol)   1701
PPTP (Point-to-Point Tunneling Protocol) 1723 1723
RADIUS (Remote Access Dial In User Service)   1812, 1813
RDP (Remote Desktop Protocol) 3389 3389
Diameter (AAA protocol, can replace RADIUS) 3868  

Miscellaneous

Service TCP UDP
DNS 53 53
DHCP   67, 68
HTTP 80  
HTTPS 443  
Kerberos 88 88
NNTP (Network News Transfer Protocol) 119  
MS-SQL-S (Microsoft SQL Server) 1433  
SNMP (Simple Network Management Protocol)   161
SNMP Trap   162
LDAP (Lightweight Directory Access Protocol) 389, 636 (TLS) 389, 636 (TLS)
Syslog   514

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