Port directory — page 2

SNMP trap port for network management and monitoring alerts

Border Gateway Protocol port for internet routing information exchange

AppleTalk Routing Maintenance

IMAP3 protocol port for mail retrieval and management

Timestamp Protocol port for time synchronization and timestamp services

ODMR，On DemandMailDelivery

HP OpenView HTTPs proxyProgram

AURP, AppleTalk Upgrade RoutingProtocol

LDAP (Lightweight Directory Access Protocol) port

HTTPS normally uses 443. HTTP/1.1 and HTTP/2 commonly use TCP/TLS; HTTP/3 uses QUIC over UDP, so TCP alone does not cover every deployment.

SMB/CIFS (Server Message Block) protocol port for file and printer sharing

Kerberos password change port for password modification and key management

Port 465 is used for mail submission with implicit TLS: the TLS handshake begins immediately after the TCP connection.

IPSec (Internet Protocol Security) IKE (Internet Key Exchange) port

Syslog system log protocol port for log transmission

Routing Information Protocol port for network routing information exchange

Extended File Transfer Protocol port for enhanced file transfer services

NNTP over SSL port for secure newsgroup services

IMAP over SSL port for secure mail retrieval

Port 587 is for message submission, commonly from a mail client to its provider. Distinguish it from server-to-server relay on port 25.

LDAP over SSL port for secure directory service access

FTP data transfer over SSL port for secure FTP data transmission

TCP 990 is implicit-mode FTPS: the TLS handshake begins the moment the client connects, with no AUTH TLS negotiation. The explicit variant (port 21 + AUTH TLS) is more common today, but many older clients and appliances still default to 990.

Port 993 provides IMAP mailbox access over implicit TLS. It is for reading and synchronizing mail, not SMTP submission.