SIP Port Tester
The generic port tester opens a TCP connection, which tells you nothing about a SIP endpoint on UDP — the usual case. This sends a real OPTIONS request and reports what came back, so a 200 OK proves the SIP stack is answering rather than just that a port is open.
Sends a real SIP OPTIONS request from this server and shows what came back. A 200 OK proves a SIP stack is answering — which an open TCP port on its own does not. Private and reserved addresses are rejected.
- Round trip
- User-Agent
- Server
- Allow
- Supported
- Contact
A 403 still proves the endpoint is alive and reachable — it simply does not accept requests from this server's IP address. For a trunk that is the correct answer to an unauthorised probe.
Raw exchange
What was sent, and what came back.
Request
Response