Expansion Stages and System Capacity
41
Aastra 470 as of R1.2
syd-0337/1.2 – R1.2 – 11.2011
3. 2. 4
DSP Resources
DSP resources are used for complex signal processing functions. (DSP stands for
Digital Signal Processor). They provide functions for conference circuits, DTMF
sender and receiver, compression of voice data, etc. Two DSP chips are perma-
nently fitted to the call manager card.
A DSP chip on the call manager card is allocated to fixed functions, which can be
used without licences (see
The functions of the second DSP chip can be selected to suit requirements. The
functions are partly subject to licence (see
The basic resources of the communications server can be expanded by fitting DSP
modules (see
) and IP media modules (see
). The functions of the DSP chips on the DSP modules can also be con-
figured.
Fixed DSP functions on the call manager card
The table below provides an overview of fixed DSP functions on the call manager
card. Except for the Enterprise Voice Mail channels no licences or additional hard-
ware are required to be able to use the functions.
Tab. 14
System modules on the call manager card
Max. number of simultaneous ...
Number of
entries
Circuits for the functions three-party conference and six-party conference
10
Circuits for the features intrusion and silent intrusion
10
Circuits for the Call Waiting function
6
DTMF sender
9
DTMF receiver
16
Dialling tone receiver
2
Busy tone receiver
5
FSK receiver for CLIP detection on analogue network interfaces
2
Basic voice mail channels (G.711)
1)
1)
The voice channels of the basic voice mail can be used without a licence, subject to the following re-
strictions: Voice memory capacity approx. 20 minutes, no e-mail notification in the event of new voice
messages. With a licence, the basic voice mail can be expanded with the Auto Attendant function.
2
Enterprise voice mail channels (G.711)
2)
2)
Licences required
8