To limit the number of VoIP channels:
� Set the status of the ports you wish to disable (starting from the highest-numbered port) to OUS. For example, if you wish to use only 10 of the available 16 VoIP channels (i.e., disable 6 channels), set the ports 8, 7, and 6 to OUS as shown below:
In this case, the equation for bandwidth calculation, based on the previous example, will be changed as follows: Required Bandwidth = (No. of Fax Machines � Required Bandwidth for the G.711 CODEC) + [(10 - No. of Fax Machines) � Required Bandwidth for Voice Communication] = (2 � 87.2) + [(10 - 2) � 31.2] = 424 (kbps)
A1.2
Network Configuration
You must evaluate the structure of the existing network to see if a VoIP network can be implemented. Below are the points that should be taken into your evaluation.
Is the IP network a managed network?
A VoIP network should be implemented on a managed IP network such as Frame Relay, Leased Line, or IP-VPN (Virtual Private Network). An unmanaged network, such as the Internet (including an Internet VPN), cannot be used to employ a VoIP network because delays and loss in data transmission can cause huge degradation in speech quality.
