Mitel 6867i Premium, Administrator'S Manual

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Global SIP Settings
4-90
The matrix below details DTMF behavior when the out-of-band DTMF and DTMF method
settings are configured in various scenarios:
RTP ENCRYPTION
The IP Phones include support for Secure Real-time Transfer Protocol (SRTP), using Session
Description Protocol Security (SDES) key negotiation, for encryption and authentication of
RTP/RTCP messages sent and received by the Mitel IP phones on your network.
As administrator, you specify the global SRTP setting for all lines on the IP phone. You can
choose among three levels of SRTP encryption, as follows:
•
SRTP Disabled (default
): IP phone generates and receives non-secured RTP calls. If the
IP phone gets called from SRTP enabled phone, it ignores SRTP tries to answer the call
using RTP. If the receiving phone has SRTP only enabled, the call fails; however, if it has
SRTP preferred enabled, it will accept RTP call.
•
SRTP Preferred
: IP phone generates RTP secured calls, and accepts both secured and
non-secured RTP calls. If the receiving phone is not SRTP enabled, it sends non-secured
RTP calls instead.
•
SRTP Only
: IP phone generates and accepts RTP secured calls only; all other calls are
rejected (fail).
You can override the global setting as necessary, configuring SRTP support on a per-line basis.
This allows IP phone users to have both secured and unsecured lines operating on the same
phone.
When an active call is using SRTP (i.e. when an SRTP enabled IP phone initiates a call and
the receiving phone is also SRTP enabled) and the transport protocol is set to TLS, the IP
Phone UI displays a “lock” icon, indicating that the call is secure. If one of the phones does not
WEB UI SETTING/CONFIGURATION
PARAMETER SETTING DTMF BEHAVIOR
DTMF
METHOD/
SIP DTMF
METHOD FORCE RFC2833
OUT-OF-BAND DTMF/
SIP OUT-OF-BAND
DTMF SIP INFO IN-BAND DTMF OUT-OF-BAND
DTMF (RFC2833)
RTP (0) Disabled (0) No Yes No
RTP (0) Enabled (1) No No Yes
SIP INFO (1) Disabled (0) Yes No No
SIP INFO (1) Enabled (1) Yes No Yes
RTP and SIP
INFO (2) Disabled (0) Yes Yes No
RTP and SIP
INFO (2) Enabled (1) Yes No Yes