Port 115: SFTP (legacy)

Port 115 is the Simple File Transfer Protocol, a simplified, rarely used file transfer scheme from the early internet. It is unrelated to the SFTP most people mean today, which is SSH File Transfer Protocol running over port 22.

TCPFile transferUnencrypted by defaultIANA assigned
Port number115
ServiceSimple File Transfer Protocol
ProtocolTCP
CategoryFile transfer
Default encryptionNo
Security note. Port 115 is not encrypted by default. Restrict it to trusted networks, or use an encrypted alternative where one exists, to avoid exposing credentials and data in transit.

How do I check whether port 115 is open?

Port 115 carries TCP, so a connection either completes its handshake or it does not, which makes the check definitive.

QuestionCommandWhat to know
Is it open on a remote host?nc -vz example.com 115A TCP handshake either completes or it does not, so netcat gives a definitive answer in one line.
Same check on WindowsTest-NetConnection example.com -Port 115Built 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 ':115 'Lists the process bound to port 115 on Linux. On macOS use lsof -nP -iTCP:115 -sTCP:LISTEN, on Windows netstat -ano | findstr :115

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 115 used for?

Port 115 is the Simple File Transfer Protocol, a simplified, rarely used file transfer scheme from the early internet. It is unrelated to the SFTP most people mean today, which is SSH File Transfer Protocol running over port 22.

Is port 115 TCP or UDP?

Port 115 (SFTP (legacy)) uses TCP.

Is port 115 secure?

Port 115 is not encrypted by default. Where possible, use an encrypted alternative or tunnel it over TLS or a VPN.

Should I open port 115 on my firewall?

Only if you specifically need SFTP (legacy). Expose it to the smallest set of trusted sources, and never open database or Windows-service ports to the whole internet.