Expansion Stages and System Capacity
47
Aastra 470 as of R3.2
syd-0337/1.6 – R3.2 – 09.2014
DSP modules are stacked on the call manager card and do not take up any slots for
interface cards (see
"Fitting DSP modules", page 107
). The different types of mod-
ules can be used as a mix.
Tab. 17
DSP modules
Compared with DSP modules, modules with the designation DSPX are fitted with
more powerful DSP chips. They are used to transmit VoIP data among others using
the SRTP protocol (Secure VoIP).
Allocatable functions
One or more functions can be allocated to the individual DSP chips on the DSP
modules and DSP chip on Call Manager card CPU1. For this the DSP chips have to
be loaded with different firmware. The additional DSP resources can be used for
DECT telephony, Voice over IP, fax transmissions, audio services, integrated mobile
phone, additional dial tone and busy tone recipients on many analogue network
interfaces FXO or for CAS (signalling protocol for PRI network interface in certain
countries). This means that for each DSP chip a specific number of voice channels is
available for the corresponding functions. Some of these functions are subject to a
licence (see also
Functions are allocated in WebAdminin the DSP configuration (
=ym
).
•
DECT
Operation of a DECT system on DSI interfaces with cordless phones. The voice
data must be transformed on connections between DECT and non-DECT end-
points. This process requires DSP capacity.
Purely DECT-DECT connections set up already do not require any DSP resources.
On the other hand, DSP resources are required to set up connections.
DECT channels can be used without a licence.
•
VoIP
Connections between IP and non-IP endpoints are made via an IP media gate-
way. This is carry out by the integrated standard media switch that switches VoIP
channels for call connections in the IP network. The Standard Media Switch uses
Type
Number of DSP chips
per module
Max. number of modules
per system
SM-DSPX1
1
2
SM-DSPX2
2
SM-DSP1
1)
1)
Although no longer available, the module is still supported.
1
SM-DSP2
2