Lucent Technologies Octel Unified Messenger Concepts and Planning Guide 101-1620-005 - Manual (Page 33)

Sizing the system
101-1620-005 2-7
PBX integration
device sizing As described in “PBX integration” on page 3-10, PBX integrations are
accomplished by different methods depending on the PBX type and the
capabilities of the PBX. Although all PBX Integration Devices (PIDs)
perform the same basic functions, they all accomplish it in a slightly
different manner. Therefore, the number of PIDs required to support a
given number of ports varies based on:
n The number of integrated ports.
n The type of PID used.
n The incoming call volume during the busy hour.
Sizing outgoing call
features: Intercom
Paging and OctelNet Outgoing call features include intercom paging and OctelNet message
delivery. These features require the user of a port by the voice server to
place an outgoing call.
The traffic generated by these features can significantly affect the GOS if
this traffic is not included in the estimate of busy hour offered traffic. If
outcall delivery traffic is managed so that the majority of it occurs outside
of the busy hour, the impact on busy hour GOS is minimized. For
instance, network delivery schedules can be defined to allow only urgent
messages from priority subscribers to be delivered during the busy period.
If a large amount of outcall traffic is expected during the busy hour, it may
be preferable to size a separate group of outgoing ports and dedicate them
to outcalling applications only.
For a conservative estimate of the number of ports required for outgoing
OctelNet messages, use this calculation:
Number of ports = 1 + (average message length * estimated daily
number of messages) / total daily duration of the window during
which OctelNet is free to outcall.
Note: When using this calculation, the following is assumed:
n The ports are not taken up by other outgoing calls.
n The schedule is the same for all priority messages.