Overview 15
—Menu selection and call transfer time is 30 seconds, with a completed call duration of 180 seconds.
—Busy Hour (BH) Auto Attendant usage is 0.35 calls per hour for each Microsoft Unified Messaging user.
•Auto Attendant operation requires the usage of two SIP trunks, which remain in use for the duration of the call.
•If Microsoft Unified Messaging system usage differs from the call model described for the purpose of SIP trunk table calculations, it is the responsibility of the customer to monitor the actual usage of the system and ensure that there are sufficient SIP trunks available for use.
Number of | Typical | Typical BH | Erlangs | Number of | Number of | Number of |
UM Users | BH Call | CCS | (ccs/36) | SIP Trunks | SIP Trunks | SIP Trunks |
| Duration |
|
| (Erlang B | (Erlang B | (Erlang B, |
| (seconds) |
|
| P05 Grade | P01 Grade | |
|
|
|
| of Service) | of Service) | ng) |
|
|
|
|
|
|
|
50 | 15000 | 150 | 4.17 | 8 | 10 | 24 |
|
|
|
|
|
|
|
100 | 30000 | 300 | 8.33 | 13 | 16 | 33 |
|
|
|
|
|
|
|
200 | 60000 | 600 | 16.67 | 22 | 26 | 49 |
|
|
|
|
|
|
|
500 | 150000 | 1500 | 42 | 48 | 55 | 89 |
|
|
|
|
|
|
|
1000 | 300000 | 3000 | 83 | 88 | 99 | 147 |
|
|
|
|
|
|
|
2000 | 600000 | 6000 | 167 | 170 | 187 | 254 |
|
|
|
|
|
|
|
3000 | 900000 | 9000 | 250 | 250 | 273 | 355 |
|
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Nortel Communication Server 1000
Communication Server 1000 with Microsoft Exchange Server 2007 Unified Messaging Fundamentals
24 October 2008
