I would like to offer a small SIP service to my family and friends (~10 people). I do not want to use external SIP providers so I am planning to set up my ASUS RT-N66U to handle all the necessary services. I have never set up a SIP system before and I am a complete noob in this subject. (Though I have previously used SIP both directly from a public IP to a public IP and with a 3rd party provider.) Which software should I use? Asterix, OpenSIPS, Kamailio? Premises: It should work with Tomato and N66U The N66U has a public IP address The clients do not have public IP addresses The clients are all soft phones on Linux, OS X, Windows and Android. The server should be as simple and lightweight as possible: basically the service just needs to connect the peers to each other (and possibly authenticate... or is the authentication done between peers?) I also want to use encryption: TLS and SRTP (but I don't know if this concerns the service at all or is this handled between the clients?) Thanks!