What is the default port used by LDAP?

The default port used by LDAP (Lightweight Directory Access Protocol) is 389. This port is designated for standard LDAP communication and is used for querying and modifying directory services running over TCP/IP.

LDAP operates over this port to facilitate access to directory services for organizations, allowing clients to perform operations like searching for user accounts or retrieving attributes associated with those accounts.

To provide a bit of context on the other options: Port 636 is often used for LDAP over SSL (Secure Sockets Layer), providing a secure connection. Port 110 is used by the POP3 (Post Office Protocol version 3) for email retrieval, while port 25 is traditionally used for SMTP (Simple Mail Transfer Protocol) for sending emails. Understanding these port assignments is important for networking and system administration, especially when configuring services or troubleshooting connectivity issues.