ISDN/DECT Synchronisation
78
Forum Gateway 560
when seizing a bundle. This means that TDM terminals preferably seize
external TDM lines on the same Forum Gateway 560.
Note:
TDM terminals on the same Forum Gateway 560 do not seize a
MGW channel during call mode, however, the terminals do
briefly seize a MGW channel for the dial tones while estab-
lishing the call connection.
The number of required Media gateway interface cards Forum 550 Media
Gateway Card depends on the possible call load at peak times and on the
number of TDM terminals and TDM lines connected to the
Forum Gateway 560.
TDM connections with connected Forum Gateways 560
One way of optimising the number of required Media gateway interface cards
is connecting Forum Gateways 560 (see
Forum Gateway 560 Connection via
starting on page 133). This means that MWG channels on
the MGW card of the connected Forum Gateway 560 can be seized. In
addition, TDM calls between Forum Gateways 560 do not seize a MGW
channel. Because the maximal length of a PCM-V cable must not exceed
50 cm, connecting Forum Gateways 560 cannot be used with a floorplan
(see above).
ISDN/DECT Synchronisation
The IP-based connection between the Forum 5004/5008/5012
communications system and a Forum Gateway 560 does not allow
transmission of a TDM synchronisation signal. The TDM synchronisation
signal is, however, generally necessary for operating DECT base stations
Gateway
Gateway
TDM
TDM
TDM
PCM-V