User's Manual
FIRMWARE VERSION 1.0.1.14      GXP2130/GXP2140/GXP2160 USER MANUAL   Page 53 of 84 
a session timer when it receives inbound calls. 
Force Timer 
If Force Timer is set to "Yes", the phone will use the session timer even if the 
remote party does not support this feature. If Force Timer is set to "No", the 
phone will enable the session timer only when the remote party supports this 
feature. To turn off the session timer, select "No". 
UAC Specify Refresher 
As a Caller, select UAC to use the phone as the refresher; or select UAS to 
use the Callee or proxy server as the refresher. 
UAS Specify Refresher 
As a Callee, select UAC to use caller or proxy server as the refresher; or select 
UAS to use the phone as the refresher. 
Force INVITE 
The Session Timer can be refreshed using the INVITE method or the UPDATE 
method. Select "Yes" to use the INVITE method to refresh the session timer. 
Account x -> SIP Settings -> Security Settings 
Check Domain 
Certificates 
Defines whether the domain certificates will be checked or not when TLS/TCP 
is used for SIP Transport. The default setting is "No". 
Validate Incoming 
Messages 
Defines whether the incoming messages will be validated or not. The default 
setting is "No". 
Check SIP User ID for 
incoming INVITE 
If set to "Yes", SIP User ID will be checked in the Request URI of the incoming 
INVITE. If it doesn't match the phone's SIP User ID, the call will be rejected. 
The default setting is "No". 
Accept Incoming SIP 
from Proxy Only 
When set to "Yes", the SIP address of the Request URL in the incoming SIP 
message  will be  checked. If it doesn't match  the SIP server address  of the 
account, the call will be rejected. The default setting is "No". 
Authenticate Incoming 
INVITE 
If set to "Yes", the phone will challenge the incoming INVITE for authentication 
with SIP 401 Unauthorized response. The default setting is "No". 
Account x -> Audio Settings 
Send DTMF 
Specifies  the  mechanism  to  transmit  DTMF  digits.  There  are  3  supported 
modes: in audio which means DTMF is combined in the audio signal (not very 
reliable with low-bit-rate codecs), via RTP (RFC2833), or via SIP INFO. 
DTMF Payload Type 
Configures the payload type for DTMF using RFC2833. The default value is 
101. 
Preferred Vocoder 
7 different vocoder types are supported on the phone, including G.711 U-law 
(PCMU),  G.711  A-law  (PCMA),  G.729A/B,  G.722  (wide  band)  and  G72-32. 
Users  can  configure  vocoders  in  a  preference  list  that  is  included  with  the 
same preference order in SDP message. 
Use First Matching 
Vocoder in 200OK SDP 
When  set  to  "Yes",  the  device  will  use  the  first  matching  vocoder  in  the 
received 200OK SDP as the codec. The default setting is "No". 
SRTP Mode 
Enables  the  SRTP  mode  based  on  your  selection.  The  default  setting  is 










