Reference Manual

Table Of Contents
Channel Distribution Function
RSL Radio Signalling Link. Layer 2
communication link for trafcal services
on A-bis.
Terrestrial Channel Terrestrial channels are physical channels
for communication with, for example, the
BSC over the Transport Network. There
are different types of terrestrial channels,
dependent on their use:
Terrestrial Signalling channels
Terrestrial Trafc channels
Terrestrial signalling channels are used for
LAPD signalling only.
Unoccupied Terrestrial Channel
An unoccupied terrestrial channel is a
physical channel which can be used as,
but is currently not used as, a terrestrial
signalling channel or as a terrestrial trafc
channel.
50.3 Functions
The CDF (Channel Distribution Function) switches channels between
the entities connected to the switch. See gure below:
Channel distribution
Channel distribution
Transport network
interface
01_0297B
TRX
Signalling
(OML/RSL)
Air timeslot
resource (traffic)
CF
Concentrator
Figure 106 Channel distribution function (CDF)
All connections through the switch are congured by A-bis commands
as described within the context of Functionality Administration. The
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EN/LZT 720 0008 R1A
2001-06-26
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