What is the best linux-compatibile open source with encryption alternative at the moment? The wiki page shows that many haven't been updated in quite some time (Twinkle). Does anybody have experience with Blink?
I personally like SFLPhone [1]. It's developed by the fine folks from Savoir-faire Linux [2] and supports encryption. Here is a guide how to configure it to encrypt traffic between the client and an Asterisk server [3].