Port 1512: WINS
Port 1512 is WINS, the Windows Internet Name Service that resolves NetBIOS computer names to IP addresses across routed networks. Microsoft has deprecated it in favor of DNS, but it still appears in some legacy Active Directory environments.
| Port number | 1512 |
|---|---|
| Service | Windows Internet Name Service |
| Protocol | TCP/UDP |
| Category | Windows |
| Default encryption | No |
How do I check whether port 1512 is open?
Port 1512 carries TCP, so a connection either completes its handshake or it does not, which makes the check definitive.
| Question | Command | What to know |
|---|---|---|
| Is it open on a remote host? | nc -vz example.com 1512 | A TCP handshake either completes or it does not, so netcat gives a definitive answer in one line. |
| Same check on Windows | Test-NetConnection example.com -Port 1512 | Built into PowerShell. TcpTestSucceeded in the output is the answer; telnet is not installed by default on modern Windows. |
| What is listening locally? | ss -tlnp | grep ':1512 ' | Lists the process bound to port 1512 on Linux. On macOS use lsof -nP -iTCP:1512 -sTCP:LISTEN, on Windows netstat -ano | findstr :1512 |
| Is it open on a remote host? | sudo nmap -sU -p 1512 example.com | UDP has no handshake, so there is nothing to complete. nmap infers the state from whether an ICMP port-unreachable comes back, needs root, and is slow and easy to misread. A silent port may be open, filtered, or simply not replying to a probe it does not recognise. |
| What is listening locally? | ss -ulnp | grep ':1512 ' | Shows the UDP socket bound to port 1512. This is the reliable way to answer the question, because you are asking the host itself rather than guessing from outside. |
Replace example.com with the host you are testing. A blocked port and a port with nothing listening on it look identical from the outside, so if a service should be running, check locally before blaming the firewall.
Frequently asked questions
What is port 1512 used for?
Port 1512 is WINS, the Windows Internet Name Service that resolves NetBIOS computer names to IP addresses across routed networks. Microsoft has deprecated it in favor of DNS, but it still appears in some legacy Active Directory environments.
Is port 1512 TCP or UDP?
Port 1512 (WINS) uses TCP/UDP.
Is port 1512 secure?
Port 1512 is not encrypted by default. Where possible, use an encrypted alternative or tunnel it over TLS or a VPN.
Should I open port 1512 on my firewall?
Only if you specifically need WINS. Expose it to the smallest set of trusted sources, and never open database or Windows-service ports to the whole internet.