Review on Zentera Systems Inc by Justin Ferguson

It’s best to use it in combination with other products, e.g., WebRTC soft phones such as Polycom or MumbleSoft etc.. We found that this product doesn't support many protocols which are very important like SDP/SSCP protocol. Sometimes, we could not send some calls because of firewall blocking our requests from sending RTP streams even though they were allowed by policy rules set up! This is one kind of issue I faced when using any VPN software including Cisco AnyConnect Softphone Client 1-800 number dialing feature provided through VpnService Gateway Server from another provider.