From SwyxWare 2011 on, SwyxWare supports the encryption of call data via "Secure Real Time Transport Protocol" (SRTP). The protocol, designed for real-time communication, means security for voice data transmission. The data is encrypted, making listening to calls impossible.

The terminal devices of the SwyxPhone Lxxx series and SwyxIt! support this technology, and can be used for calls via SRTP. When encryption is active, a symbol showing this appears on the phone display. For further information please refer to chapter Encryption.