Disabled

STRP is not used for connections.

Best Effort

Support both RTP and SRTP. Use SRTP if matching SRTP settings can be negotiated with the remote end. This requires the remote end to support srtp rfc5939 (capability negotiation for SRTP). Otherwise use RTP. Note that E129 phones does not support Best Effort.

Enforced

Use SRTP only. The call is not allowed if the remote leg does not support matching SRTP.

Advanced Settings

After selecting either Best Effort or Enforced as the STRP method, it is recommended that all other SRTP settings are left at their defaults.

The default SRTP flags and crypto suite settings were chosen so that they work with all Avaya H323 and SIP devices. For example, the majority of Avaya implementations don’t support RTCP encryption and Avaya H323 phones only support the SHA_80 crypto suite.