We have around 10 years of experience in VoIP development. We have developed a wide range of VoIP dialers for iPhone, android, WindowsPhone, Blackberry etc. We have worked on VOIP protocols like SIP, RTP, RTCP, SRTP, SDP, H.323, and Q.931 etc. Also we have developed VOIP apps for both audio & video communication along with realtime messaging. We will encrypt the data that will be sent over network in desired manner. We have used Base64, Rc4, AES, Diffie Hellman and other symmetric and asymmetric encryption algorithms. We will provide you any encryption that will be needed. For reference to our voip experience, please review our following dialers and apps available on app store and google play. https://play.google.com/store/apps/details?id=com.nathtel.nathtelex&hl=en Spaxtel https://itunes.apple.com/us/app/international-calls-spaxtel/id466322709?mt=8 Flicall https://itunes.apple.com/us/app/flicall-international-calling/id1002340825?mt=8 TalkHome https://itunes.apple.com/us/app/talkhome-app/id993137075?mt=8 Funbers https://itunes.apple.com/us/app/funbers/id657504259?mt=8 Flexiroam https://play.google.com/store/apps/details?id=com.flexiroamx&hl=en Mobilink Raendel https://itunes.apple.com/us/app/raendel/id932315225?mt=8 I would appreciate to discuss further in details on your project to have a better understanding and clear view of different horizons that can help me to provide you with exact time & Cost Estimation. We are into software products development included web based and mobility solutions since 2006. We do have a dedicated team of 70 engineers working with us. Some of our flagship products include voice call encryption solutions, encrypted messaging solutions and call masking solutions, which are quite challenging. Anything which is technically feasible on mobile, we do have expertise to execute it. We are technology partner with Samsung. We really look forward to work on this opportunity. Thanks and Regards Shubham