Nortel Networks NN43001-122 User Manual
Page 15
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
UM Users
Typical
BH Call
Duration
(seconds)
Typical BH
CCS
Erlangs
(ccs/36)
Number of
SIP Trunks
(Erlang B
P05 Grade
of Service)
Number of
SIP Trunks
(Erlang B
P01 Grade
of Service)
Number of
SIP Trunks
(Erlang B,
Non-blocki
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
Nortel Communication Server 1000
Communication Server 1000 with Microsoft Exchange Server 2007 Unified Messaging Fundamentals
NN43001-122
02.04
24 October 2008
Copyright © 2008 Nortel Networks
.