VOIP lib app multiplatform can be based on opensource components

write ios/android/windows/linux/osx voip library will be used by our app for VOIP/VIDEO communication on supported platforms API exposed as easy socket interface (websockets for js) Traffic needs to be obfuscated strongly so it can work in countries like UAE (tunnel) app needs to go our our central servers first (tunneling) and then from there SRTP over SIP infrastructure needs to be ultra secure, need to think about how to exchange the keys best & how to encrypt lib needs to work with e.g. 10 tunnel end points & automatically chose the best tunnel SPECIALISTS ONLY PLEASE you need to be able to show working projects done in this domain