User's Manual

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GXP17xx Administration Guide
Use First Matching
Vocoder in 200OK SDP
When it is set to "Yes", the device will use the first matching vocoder in the
received 200OK SDP as the codec. The default setting is "No".
Disable Multiple m line
in SDP
When it is set to “No”, the device will reply with multiple m lines; Otherwise, it
will reply 1 m line. The default setting is “No”.
SRTP Mode
Enable SRTP mode based on your selection from the drop-down menu. The
default setting is "Disabled".
Crypto Life Time
Enable or disable the crypto life time when using SRTP. If users set to disable
this option, phone does not add the crypto life time to SRTP header. The
default setting is “Yes”.
Symmetric RTP
Defines whether symmetric RTP is supported or not. The default setting is
"No".
Silence Suppression
Controls the silence suppression/VAD feature of the audio codec G.729. If set
to "Yes", when silence is detected, a small quantity of VAD packets (instead
of audio packets) will be sent during the period of no talking. If set to "No", this
feature is disabled. The default setting is "No".
Voice Frames Per TX
Configures the number of voice frames transmitted per packet. When
configuring this, it should be noted that the "ptime" value for the SDP will
change with different configurations here. This value is related to the codec
used and the actual frames transmitted during the in payload call. For end
users, it is recommended to use the default setting, as incorrect settings may
influence the audio quality. The default setting is 2.
G.726-32 Packing Mode
Selects "ITU" or "IETF" for G726-32 packing mode. The default setting is
“ITU”.
Jitter Buffer Type
Selects either Fixed or Adaptive for jitter buffer type, based on network
conditions. The default setting is "Adaptive".
Jitter Buffer Length
Selects jitter buffer length from 100ms to 800ms, based on network
conditions. The default setting is "300ms".
Account x  Call Settings
Early Dial
Selects whether or not to enable early dial. If it's set to "Yes", the SIP proxy
must support 484 responses. Early Dial means that the phone sends for each
pressed digit a SIP INVITE message to SIP server. SIP server looks into its
extensions and, if no match happened yet, it sends back a "484 Address
Incomplete" message. Otherwise, it executes the action. The default setting is
"No".
Dial Plan Prefix
Configures the prefix to be added to each dialed number.
Dial Plan
A dial plan establishes the expected number and pattern of digits for a
telephone number. This parameter configures the allowed dial plan for the
phone.