Avaya 555-245-600 manual Example 5 TDM and media processing usage

Resource sizing

Example 5: TDM and media processing usage

Consider the COI matrix in Table 32: Completed COI matrix for Example 4: Expanded COI

matrices on page 196 in Example 4: Expanded COI matrices. A set of nine cells corresponds to calls originated in Site 1 and terminated in Site 1 (that is, the upper left group of nine cells, arranged in a three-by-three submatrix). The uppermost and leftmost cell of those nine cells indicates that the IP-to-IP call usage for Site 1 intrasite calls is 12.7 Erlangs. The other four cells of those nine cells which fall in a row or column that is labeled “I” indicate that the total call usage between IP endpoints and circuit-switched endpoints (including PSTN trunks) within Site 1 is (7.5 + 30.9 + 7.5 + 30.9) = 76.8 Erlangs. The remaining four cells of those nine cells indicate that the total call usage between two circuit-switched endpoints (including PSTN trunks) within Site 1 is (4.4 + 18.1 + 18.1 + 0) = 40.6 Erlangs. Analogous numbers for intrasite usages that correspond to the other two sites are similarly derived.

Next, consider the three-by-three submatrix that corresponds to calls from Site 1 to Site 2. The total call usage from Site 1 to Site 2 which involves an IP endpoint in Site 1 can be determined by adding the three cell values of those nine cells that correspond to IP endpoints in Site 1.

Specifically, the total is (5.2 + 2.3 + 0) = 7.5 Erlangs. The total call usage from Site 1 to Site 2 which involves a circuit-switched endpoint (including PSTN trunks) in Site 1 can be determined by adding the remaining six cell values of those nine. Specifically, that total is (3.1 + 1.4 + 0 + 0 + 0 + 0) = 4.5 Erlangs.

The total call usage from Site 1 to Site 2 which involves an IP endpoint in Site 2 can be determined by adding the three cell values of those nine that correspond to IP endpoints in Site

2.Specifically, the total is (5.2 + 3.1 + 0) = 8.3 Erlangs. And finally, the total call usage from Site

1to Site 2 which involves a circuit-switched endpoint (including PSTN trunks) in Site 2 can be determined by adding the remaining six cell values of those nine. Specifically, that total is (2.3 + 1.4 + 0 + 0 + 0 + 0) = 3.7 Erlangs. Analogous numbers for the other five combinations of intersite usages are similarly derived. The results are shown in Table 33: Re-categorization of CURs from Table 32 on page 206.

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