Port 1434: MSSQL Browser
Port 1434 is the SQL Server Browser service, which listens for UDP requests and reports back which dynamic TCP port a named SQL Server instance is actually using. It exists because named instances do not use the fixed port 1433.
| Port number | 1434 |
|---|---|
| Service | Microsoft SQL Server Browser service |
| Protocol | UDP |
| Category | Databases |
| Default encryption | No |
Frequently asked questions
What is port 1434 used for?
Port 1434 is the SQL Server Browser service, which listens for UDP requests and reports back which dynamic TCP port a named SQL Server instance is actually using. It exists because named instances do not use the fixed port 1433.
Is port 1434 TCP or UDP?
Port 1434 (MSSQL Browser) uses UDP.
Is port 1434 secure?
Port 1434 is not encrypted by default. Where possible, use an encrypted alternative or tunnel it over TLS or a VPN.
Should I open port 1434 on my firewall?
Only if you specifically need MSSQL Browser. Expose it to the smallest set of trusted sources, and never open database or Windows-service ports to the whole internet.