Port 1433 supports Microsoft SQL Server and ms-sql-s (UDP reference coverage) across distinct transports. Review each protocol before writing firewall or monitoring policy.
Default SQL Server database engine endpoint.
Applications and administration tools connecting to a default SQL Server instance.
Client to server
Do not expose database listeners publicly. Require encrypted connections, least-privilege logins and network allow-listing.
ms-sql-s (UDP reference coverage) is documented as a network service convention for port 1433 over UDP.
Use this reference entry when identifying or validating systems documented to use 1433/UDP.
Varies
Confirm the listening process and current vendor documentation before permitting traffic; a listed convention does not prove the active service or its security posture.