Mizu VoIP Tunnel - Version 4.2.1 Mizu VoIP tunnel is a special VoIP server software whose task is to encrypt all communication from/to the clients and to forward the calls to your server(s) using the common SIP protocol. This UDP level encryption will not add any overhead to your network traffic and can work completely transparent. Several ISPs, Telco's and countries like Dubai or Oman are filtering VoIP or degrading the media in order to force a consumer to use their own VoIP or traditional PSTN services. Using Mizutech built-in encryption you can forget all about these issues. These solutions can work in VoIP networks provided by Mizutech or can be seamlessly integrated in your network without any configuration change in your existing servers. The encryption will allow VoIP usage in any countries bypassing all kind of VoIP filtering (unless srtp encryption which can be easily detected by VoIP filters)