AVT Titan, Руководство оператора

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3 – 8 4 040 7448 329657 (04.97) PC-SW 4.5
C H A P T E R 3 : O P E R A T I O N W I T H A P C
The following limitations should be noted:
3.3.8.6 DATA RATE
This window is used to set the total data rate with which the next connection
is to be set up. If the LINE interface that has been selected is 1..6
∗
X.21 and
three terminal adapters have been connected, for example, the data rate
3
∗
64 kbit/s (192 kbit/s) and all lower rates can be selected. To do this, click the
required data rate with the mouse.
Note Also, if you have entered all six calling numbers in the number
block, only as many B channels are set up as have been set
here. If the an entry in the list of telephone numbers (directory)
is used, please ensure that number of entries in the directory
is as least the number of B channels that you require for the
total data rate (the total rate is saved with the configuration).
During a connection, you can switch between the selected maximum data rate
and any of the lower rates. The connection retains the maximum capacity.
The number of total data rates that can be set depends on the network inter-
face used. For ISDN connections, up to six B channels are available. If
1
∗
X.21 or RS449 are used, the TITAN system detects the clock frequency
and calculates the number of possible 64-kbit timeslots. In the E1 network,
there are 30 timeslots.
Note When you select the data rate, remember that this is the total
data rate. The actual data rates available for the transmission
of the audio and video data are lower (see SECTION 3.3.2.2).
For ISDN connections, 1.6 kbit/s are reserved in each B chan-
nel for inband signalling purposes, in non-ISDN cases, a total
of 1.6 kbit/s is reserved. If additional data is transmitted, this
also reduces the available data rate for audio and video.
3.3.8.7 OCTET TIMING
This switch is only relevant if the X.21 interfaces are used.
E1/T1: A clock is always recovered from the receive signal to read in
the received data. Further processing is with the clock set by
CLOCK SOURCE. For there to be no slip between read-in
data and processed data, these clocks must be the same. RE-
COVERED is therefore recommended as clock.
1..6
∗
X.21:
CLOCK SOURCE must be EXTERNAL, if the line equipment
is connected to X.21 interfaces and a call should be set up.
Exception: For testing (LOOP), INTERNAL clock can be sel-
ected.
1
∗
X.21:
The default clock mode is EXTERNAL. If the data transmis-
sion unit does not provide a clock, the system switches to IN-
TERNAL automatically.
RS449:
see 1
∗
X.21