Appendix A Common Applications and Port Numbers

Protocol/Application Port Number
DHCP UDP 67 (sending), 68 (receiving)
DNS UDP, TCP 53
FTP TCP 21
HTTP TCP 80
HTTPS TCP 443
ICA (CGP) TCP 1494 (2598)
LDAP TCP 389
LDAPS TCP 636
LDAP(S) to Active Directory Global Catalog TCP 3268, 3269
POP3 110
RADIUS Authentication UDP 1812, 1645
RADIUS Accounting UDP 1813, 1646
RDP and Terminal Services TCP 3389
RPC Locator Service TCP 135
SSH TCP 22
SMTP TCP 25
SNMP UDP 161
SQL Server TCP 1433
TACACS+ UDP/TCP 49
Telnet TCP 23
WINS TCP 137
WINS Replication TCP 42

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