Call usage rates
Table 27, and Table 28, respectively, for the Uniform Distribution model based on relative SUR are:
Inbound CUR to Site i
Outbound CUR from Site
= | ⎛ | total station usage in Site i ⎞ | ⋅ (total inbound CUR) | |
⎝ | ⎠ | |||
i = | ⎛ | total station usage in Site i ⎞ | ⋅ (total outbound CUR) | |
⎝ | ⎠ | |||
Intercom CUR from Site i to Site j = | ⎛ | total station usage in Site j ⎞ | ⋅ | ⎛ total intercom CUR⎞ | |
⎝ | ⎠ | ⎝originating in Site i ⎠ | |||
Example 3: Empirical approach for existing systems
Another possible means of populating the COI matrices exists for established systems. In such cases, the necessary information can be read from traffic reports. This method is particularly useful for customers who are considering an upgrade from their current equipment.
Expanded COI matrices
So far, all the discussion pertaining to COI matrices has focused on a macroscopic view of sites. In particular, all the COI matrices presented have dedicated one cell for each pair of sites. In preparation for Resource sizing on page 198, it is useful to partition each such cell into collections of smaller cells that describe the call flows between different communities of endpoint types within the sites.
One possible partitioning scheme for each site is to create the following three general endpoint categories:
●IP endpoints
●
●PSTN trunks
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