Matrix SETU VFXTH - Page 137

Matrix SETU VFXTH System Manual 132
As Interval, set the time period after which the system should send Keep Alive messages. This time
period should be less than the NAT binding timer of the router. The valid range for the UDP NAT
Keep Alive Interval is 001–999 seconds. Default: 120 seconds.
• TCP NAT Keep Alive: When SETU VFXTH is connected behind a NAT router, and SIP messages are
transported over TCP, NAT Keep Alive messages must be sent to refresh the binding in the NAT router.
• Select the TCP NAT Keep Alive check box, if you want the system to send Keep Alive messages
periodically to refresh the binding in the NAT router. Default: Disabled.
As Interval, set the time period after which the system should send Keep Alive messages. This time
period should be less than the NAT binding timer of the router. The valid range for the TCP NAT
Keep Alive Interval is 001–999 seconds. Default: 120 seconds.
SIP
• Click SIP to expand and configure the following.
• Configure the following SIP parameters.
• 100rel/PRACK: This parameter is to be configured if you want to support reliable transmission of (SIP)
provisional responses.
Select the 100rel/PRACK Enable check box, if you want the SETU VFXTH to use 100rel SIP
extension for reliable transmission of SIP provisional responses and to use PRACK (Provisional
Acknowledgement). Default: Disabled.
• SIP Over TCP: SETU VFXTH supports transporting of SIP messages over User Datagram Protocol
(UDP) as well as Transfer Control Protocol (TCP) connection. Despite the advantages that SIP over
TCP offers, it is more common to use UDP to transport SIP messages.
By default, SIP over TCP is enabled. If you want to receive SIP messages over TCP keep this option
enabled.
You must also enable ‘TCP' or 'TCP (Fallback to UDP)' on the SIP Trunk.