User's Manual Part 1
Firmware Version 1.0.0.1  UCM6200 Series IP PBX User Manual  Page 135 of 320
option is disabled. 
Music On Hold 
Select which Music On Hold class to suggest to extensions when putting 
them on hold. 
Enable LDAP 
If enabled, the batch added extensions will be added to LDAP Phonebook 
PBX list; if disabled, the batch added extensions will be skipped when 
creating LDAP Phonebook. 
Enable WebRTC Support 
If enabled, extensions will be able to login to user portal and use Web 
RTC features. 
Call Duration Limit 
Configure the maximum duration of call-blocking. 
SIP Settings 
NAT 
Use NAT when the PBX is on a public IP communicating with devices 
hidden behind NAT (e.g., broadband router). If there is one-way audio 
issue, usually it's related to NAT configuration or Firewall's support of SIP 
and RTP ports. The default setting is enabled. 
Can Direct Media 
By default, the PBX will route the media steams from SIP endpoints 
through itself. If enabled, the PBX will attempt to negotiate with the 
endpoints to route the media stream directly. It is not always possible for 
the PBX to negotiate endpoint-to-endpoint media routing. The default 
setting is "No". 
DTMF Mode 
Select DTMF mode for the user to send DTMF. The default setting is 
"RFC2833". If "Info" is selected, SIP INFO message will be used. If 
"Inband" is selected, 64-kbit codec PCMU and PCMA are required. When 
"Auto" is selected, RFC2833 will be used if offered, otherwise "Inband" 
will be used. 
Enable Keep-alive 
If enabled, empty SDP packet will be sent to the SIP server periodically to 
keep the NAT port open. The default setting is "Yes". 
Keep-alive Frequency 
Configure the number of seconds for the host to be up for Keep-alive. The 
default setting is 60 seconds. 
TEL URI 
If the end device/phone has an assigned PSTN telephone number, this 
field should be set to "User=Phone". Then a "User=Phone" parameter will 
be attached to the Request-Line and TO header in the SIP request to 
indicate the E.164 number. If set to "Enable", "Tel:" will be used instead of 
"SIP:" in the SIP request. The default setting is disabled. 
Concurrent Registrations 
The maximum endpoints which can be registered into this extension. For 
security concerns, the default value is 1. 
Other Settings 
SRTP 
Enable SRTP for the call. The default setting is "No". 
Fax Mode 
Select Fax mode for this user. The default setting is “None”. 










