Viking E-32T Series Product Manual page 22

VoIP Security
SIP Transport
By default, SIP transport is sent over UDP. For TLS transport select the 'SIP over TLS' option. This only encrypts the SIP
control traffic. For fully encrypted calls select the SIPS option and enable secure RTP below.
NOTE: SIP over TLS and SIPS will use a different port with the SIP Server/Provider, ensure this is set correctly on the VoIP Account page.
Secure RTP:
Select an option for audio encryption. By default, the audio is sent via unencrypted RTP.
Disabled: Audio is sent as unencrypted RTP.
Optional: Encrypted audio is offered when a call is set up. If the negotiation is successful VoIP audio will be sent using encrypted RTP.
Mandatory: Encrypted audio is offered when a call is set up, if the negotiation is successful the call is set up using encrypted RTP. If not,
the VoIP call is ended.
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