What port number is used by LDAP protocol?

Port 110 is the IANA-assigned port for POP3 (Post Office Protocol version 3), used to retrieve email from a mail server.

LDAP (Lightweight Directory Access Protocol) is assigned TCP and UDP port 389 by IANA for standard unencrypted directory service communication. This port is used by directory services such as Microsoft Active Directory for authentication queries, attribute lookups, and directory searches. LDAP over SSL/TLS (LDAPS) uses the separate port 636, but plain LDAP operates exclusively on 389.

Port 464 is assigned to the Kerberos password change service (kpasswd), part of the Kerberos v5 authentication protocol suite.

Port 445 is assigned to Microsoft-DS and carries SMB traffic for Windows file sharing and Active Directory replication, which is distinct from LDAP directory queries.