Grandstream Networks GRP261 Series Administration Guide

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GRP261x/GRP2624/GRP2634 Administration Guide
Version 1.0.5.48
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”.
Codec Negotiation
Priority
Configures the phone to use which codec sequence to negotiate as the
callee. When set to “Caller”, the phone negotiates by SDP codec sequence
from received SIP Invite. When set to “Callee”, the phone negotiates by audio
codec sequence on the phone. The default setting is “Callee”.
Hide Vocoder
When option Hide Vocoder is set as Yes, the coded will be hidden from call
screen as bellow. 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.
 No
 Enabled But Not forced
 Enabled and Forced
 Optional
The default setting is “No”.
SRTP Key Length
Allows users to specify the length of the SRTP calls. Available options are:
 AES 128&256 bit
 AES 128 bit
 AES 256 bit
Default setting is: AES 128&256 bit
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. Default setting is “No”.
Silence Suppression
Controls the silence suppression/VAD feature of the audio codecs except
forG.723 (pending) and G.729. If set to “Yes”, a small quantity of RTP
packets containing comfort noise will be sent during the periods of silence. If
set to “No”, this feature is disabled. Default setting is “No”
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”.
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.

Grandstream Networks GRP261 Series Specifications

General

Brand	Grandstream Networks
Model	GRP261 Series
Category	IP Phone
Language	English