Ip Networking Limit Working Example - Mitel mivoice business Engineering Manualline

Since the bandwidth is derived from the number of conversations, it is important to understand
which CODEC is used across the link (G.729a, G.711, or a combination of both).
Note: Music On Hold and messages to and from Voice Mail can be handled with G.729a,
if available.
Also, the level of networking between nodes and whether it includes PSTN trunk traffic or only
internal intercom traffic needs to be understood.
As a general guideline, consider that a single node might have a high networking traffic ratio
of 15%. For a particular node with a number of devices, the amount of traffic to and from this
node remains constant. What differs is the level of traffic destined for another particular node.
For example, 15% of traffic might be destined for the second node in a two-node system, but
7.5% is destined for each of the other two nodes in a three-node system. Obviously, in the
second scenario, less bandwidth is needed to and from a particular node, but the total per node
remains about the same.
A number of factors determine compression operation:
• Are there sufficient resources (i.e. are there enough DSP channels available)?
• Have sufficient compression licenses been acquired?
• Can the end device handle compression? Some phones can handle only G.711.
• See the application information to determine whether compression is handled.
• Is compression enabled in the Class-Of-Service options?
• Are the IP trunks (IP networking routes) configured with compression?

IP NETWORKING LIMIT WORKING EXAMPLE

Consider the following example:
• Two equal-sized systems.
• 250 IP devices/phones.
• Calls from TDM, or to TDM devices including trunks, use G.711 CODEC.
• Calls between IP devices use the G.729a CODEC.
• Traffic is typically 35% (100-65) internal, the remainder to and from PSTN trunks.
• Calls internally are typically 50% outgoing and 50% incoming.
• Traffic is rated at 6 CCS per device.
• Traffic between nodes is 15%.
Network Configuration Concepts
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