Installation, Administration and Maintenance
Aastra Telecom
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Media Server
Media Gateway
Signalling
RFP Control Interface
RTP/RTCP
SIP-Phone
OMM
(RFP in OMM mode)
Primary RFP
New secondary RFP
2.5 RFP
Synchronization
To guarantee a seamless handover if a caller moves from one RFP zone of
coverage to another RFP zone of coverage, an accurate synchronization of
the RFPs is necessary.
The RFPs are synchronized over the air interface. The first RFP to complete
start-up will transmit a signal on the air for the other RFPs to synchronize
from. If a RFP gets in sync then it will transmit a signal on the air and will be
the sync source for the next RFP. Only RFPs which can receive a
synchronization signal will become synchronized.
For the RFP to sync to another RFP the signal strength cannot drop below
–70 dBm. You must consider this requirement during the site survey.
The first active RFP will be chosen by the ADMM.
R 111
R 110
R 109
R 108
R 106
R 101
R 102
R 103
R 104
R 105
R 107
Unsynchronized RFP,
which does not receive a
signal from another RFP
Unsynchronized RFP,
which receives a signal
from another RFP and
tries to get synchronized
Synchronized RFP,
which receives and
transmits a signal on the
air interface
As long as an RFP is not in sync, no calls can be established using this RFP.
If a RFP loses the synchronization the RFP does not accept new calls (“busy
bit”). There is a delay of maximum 3 minutes until the active calls on this RFP
are finished. Then it tries to get synchronized again.
