Comrex Access NX, Руководство по эксплуатации продукта

Страница: 106 / 127

106
brIC NorMAl SEttINgS
IP connections use a concept known as ports to differentiate between different applications on the same computer.
A port is simply a number contained in the IP header, but it can be thought of as a physical opening in and out of
your computer. Most firewalls function by opening the network to traffic with only specific port numbers.
Each IP connection has a source and destination port. In most cases, the source port is unimportant, but the
destination port can determine whether or not the connection will be made. Certain incoming ports can be
firewalled to outside traffic, and in the case of more than one ACCESS unit behind a router (sharing a single public
IP address), the only way for them all to take incoming calls is to assign different incoming ports to each device.
CrossLock makes connections on UDP port 9001. Legacy Comrex audio codec connections are made on UDP port
9000. In order to accept calls from both newer and older ACCESS units, you may need to open additional ports in
your router or firewall settings.
Changing the port for incoming connections is done under System Settings .
To change the destination port of an outgoing call, you must add the port number to the IP address in the correct
format. For example, to initiate a connection to the Comrex test line at port number 5004, enter the following into
the IP address field:
70.22.155.131:5004
Note that the last four digits of the IP address are the numbers corresponding to the port at the receive point.
Be aware that the call will fail unless the ACCESS on the far end is set to receive data on that port.
IP Port - This option allows you to define the incoming UDP port for incoming IP connections. This is explained in
detail in the previous section.