Table 28: Advanced - General Settings - Grandstream Networks GAC2500 Administration Manual

Local RTP Port
Use Random Port
Disable in-call DTMF display
Enable Enterprise Contacts
Timeout Auto Search
Hide LDAP Contacts
Keep-alive Interval (s)
STUN Server
Use NAT IP
Permission to
Install/Uninstall Apps

Table 28: Advanced - General Settings

Defines the local RTP-RTCP port pair used to listen and transmit.
If it is configured with X, in channel 0 the port X will be used for audio
RTP message, the port X+1 for audio RTCP message, the port X+2 for
video RTP message and the port X+3 for video RTCP. In Channel 1,
each port number will be incremented by 4 for each message. This
increment rule will apply to other channels and other port numbers.
By default, the Account 1 will use Channel 0, Account 2 Channel 1,
Account 3 Channel 2, Account 4 Channel 3, and Account 5 Channel 4
and Account 6 Channel 5.
If an account needs to establish multiple session simultaneously, the
system will use the ports in the next available channels.
The default value is 5004. The valid range is from 1024 to 65400.
Forces the phone system to use random ports for both SIP and RTP
messages. This is usually necessary when multiple phones are behind
the same full cone NAT. The default setting is "No".
Note: This parameter must be set to "No" for Direct IP Calling to work.
Enables/disables the phone system to omit the LDAP contacts will from
LCD screen. If it is enabled, end user is not allowed to use it in the
Contact app. The default setting is "No".
Configures whether to display the matched content automatically in
search of the LDAP Contacts when timeout. If set to "No", users need to
click the Search button to search the matched contacts mentioned above.
The default is "Yes".
Enables/disables the phone system to omit the LDAP contacts will from
LCD screen. If it is enabled, end user is not allowed to use it in the
Contact app. The default setting is "No".
Specifies how the phone system will send a Binding Request packet to
the SIP server in order to keep the "ping hole" on the NAT router to open.
The default setting is 20 seconds. The valid range is from 10 to 160.
Configures the URI of STUN (Simple Traversal of UDP for NAT) server.
The phone system will send STUN Binding Request packet to the STUN
server to learn the public IP address of its network. Only non-symmetric
NAT routers work with STUN. Default setting is "stun.ipvideotalk.com".
Configures the IP address for the Contact header and Connection
Information in the SIP/SDP message. It should ONLY be used if it's
required by your ITSP. The default setting is keep the box blank
Configures the permissions for users to install/uninstall the applications.
If set to "Allow", the user is free to install/uninstall third-party apps; If set
to "Require admin password", the user need to input the correct
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