
Ask HN: How do apps build encryption in calls? Any libraries or open source? - quotz
I know it consists of separating the audio in small packets and then encrypting them before theyre being sent to another user. However, theres so many of these encrypted call apps that I am getting the feeling that its either easy to make one or theres open source stuff or libraries that can help?
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noodlesUK
Encrypted voice is very tricky to get right. One of the state of the art open
protocols is SRTP (and ZRTP). However, outside of Signal and a few others, a
fair amount of e2e encrypted voice is proprietary and aimed at the defence
market. Webrtc (including p2p) is also encrypted, but it’s not e2e unless the
calls are p2p.

One channel for information leakage is variable bitrate codecs. Have a look at
this paper. [http://www.cs.jhu.edu/~cwright/voip-
vbr.pdf](http://www.cs.jhu.edu/~cwright/voip-vbr.pdf)

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quotz
Is webrtc not p2p? I will check out SRTP! Thanks for letting me know!

