Question

1. What is the port of WebSocket?

2. What protocol does WebSocket use?

3. Does WebSocket work when the firewall blocks all but 80 and 443 ports?

Answer 1

What is the port of WebSocket?

The WebSocket handshake operates over HTTP, so the port is whatever the HTTP/WebSocket server wants to use. The standard is 80 for unencrypted HTTP, and 443 for encrypted HTTPS.

What protocol does WebSocket use?

The "WebSocket Protocol" specification is RFC 6455.

Does WebSocket work when the firewall blocks all but 80 and 443 ports?

Yes, if the HTTP/WebSocket server decides to use those ports for WebSocket connections.