Port 636: LDAPS
Port 636 is LDAPS, LDAP directory queries encrypted with TLS. It protects credentials and directory data in transit, unlike plain LDAP on port 389.
TCPAuthentication EncryptedIANA assigned
| Port number | 636 |
|---|---|
| Service | LDAP over TLS |
| Protocol | TCP |
| Category | Authentication |
| Default encryption | Yes (TLS/SSH) |
Frequently asked questions
What is port 636 used for?
Port 636 is LDAPS, LDAP directory queries encrypted with TLS. It protects credentials and directory data in transit, unlike plain LDAP on port 389.
Is port 636 TCP or UDP?
Port 636 (LDAPS) uses TCP.
Is port 636 secure?
Yes. Port 636 carries encrypted traffic by default, so data in transit is protected.
Should I open port 636 on my firewall?
Only if you specifically need LDAPS. Expose it to the smallest set of trusted sources, and never open database or Windows-service ports to the whole internet.