Definy yes.
If you are using the WebRTC engine, then the webphone can carry both the signaling and the media over TCP 80 (directly or over TURN which is built-in)
If you are using NS or Java engine then the webphone has uses our advanced tunneling module (built-in by default) which can detect the best available transport protocol to use (UDP, TCP/TLS, HTTP/HTPS) so it will automatically route both the signaling and the media over HTTP 80 if UDP and other TCP ports are blocked.

The webphone is capable to even more. It can encrypt and obfuscate all it's communication so it can be used also in countries where all VoIP is blocked. It can also bypass deep packet inspection firewalls.

Yes, of course.
Just send us the address (IP and/or domain name) of your VoIP server and we will send your trial build today.
Please send to webphone@mizu-voip.com

Ok. The trial package have been delivered.
Let's continue all further conversation by email.