Zycoo CooVox-U80 User Manual page 52

Start RTP Port/End RTP Port: The UDP ports used by CooVox IPPBX system to carry RTP voice
stream.Do not change the port numbers or you may encounter audio issue with phone calls.
DTMF Mode:The DTMF mode specifies how touch tones will be transmitted to the other
side of the call. Possible values for this field are rfc2833, inband, info, and auto.
Allow Guest: This setting determines if anonymous callers are permitted to place calls to the
CooVox IPPBX system. For security precautions please do not enable this option.
Max Registration/Subscription Time(sec): Maximum allowed time of incoming registrations
and subscriptions (seconds).
Min Registration/SubscrptionTime(sec): Minimum length of registrations/subscriptions.
Default Incoming/Outgoing Registration Time(sec): Default length of incoming/outgoing
registration.
NAT Support
When the CooVox IPPBX system is behind a NAT device and needs to communicate to the outside.
It needs to know whether it is talking to someone "inside" or "outside" of the NATted network.
For example, if you are going to deploy remote extensions you have to tell the CooVox IPPBX
system which network address/addresses are from inside and which are from outside. Below is
an example configuration.
External IP: Your static public IP address or domain name.
External Host: This issimilarto"ExternalIP"exceptthat the hostname is looked up every
"External Refresh" seconds(default 10's).
External Refresh(sec): The refresh interval of the "External Host".
Local Network Address: Your local network address/addresses.
Notice:
If you have one‐way audio or no audio issue on the remote extensions then this most probably means that NAT
support is not properly configured. Please check your configurations here.
Type of Service
Asterisk supports different QoS settings at the application level for various protocols on both
signaling and media. The Type of Service (TOS) byte can be set on outgoing IP packets for various
protocols. The TOS byte is used by the network to provide some level of Quality of Service (QoS)