VoIP: SIP-over-TLS and sRTP: Voip by Antisip

Antisip is the show-case tool for the closed-source amsip (SDP layer) which uses the open-source eXosip2 (SIP layer).

Last tested version

5.2.1-434
retested in May 2020 with 5.2.1-514

Configuration

SIP-URI Host: Options → Settings → SIP Account → Domain
SIP-URI User: Options → Settings → SIP Account → Username
SIP-over-TLS: Options → Settings → Extra → Protocol: TLS (Verify certificates)
SDES-sRTP: Options → Settings → Extra → RTP profile: RTP/AVP (+optional SRTP)
which is RTP/AVP with crypto

Software Bugs

SHA-2 Digest: does not pick MD5, continues without header Authorization, therefore is not able to register; therefore incompatible with Linphone

Security

Bugs: SDES-sRTP key with reduced entropy (keys observed were hex: 0-9a-f) fixed in Nov. 2019 with version 5.2.1-449
DNS-SRV redirection disables Hostname Validation fixed in Nov. 2019 with version 5.2.1-449

back to the other (soft) phones.