3Com 3C63400-3AC-C - PathBuilder S700 Switch, Reference Manual

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166 C
HAPTER
5: C
ONFIGURING
P
ATH
B
UILDER
S700 M
ODULES
, P
ORTS
,
AND
A
PPLICATIONS
Configuring DSX-1
CBR or E1 CBR
Modules
The PathBuilder S700 supports both a DSX-1 CBR module and a E1 CBR module.
The configuration procedure is the same for both modules, but different
parameters are available on the port configuration menu.
Configuring a CBR module involves the following tasks:
n
Setting the administrative status of the card (putting it into service and taking it
out of service)
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Configuring the ports
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Configuring the virtual interfaces
The DSX-1/E1 CBR ports support a “lite” RS-366 template. This feature works as
follows:
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From the CBR DSX/E1 Port Configuration menu, you set an Idle Timer value.
The CBR software starts an internal timer when no cell is being received. If the
amount of time you specify as the
Idle Timer expires before another cell is
received, the software shuts off cell transmission and puts the virtual circuit
into a listening mode.
n
When you configure a virtual circuit for a DSX-1/E1 CBR port for which the Port
Mode is set to Struct Data , the Add Virtual Circuit screen includes a Mode
parameter. You can set the circuit Mode to Normal , RS366 , or DBA .
For details about how to set to configure virtual circuits, see “Configuring Virtual
Circuits” later in this chapter.
n
If you set the Mode to Normal , the circuit is configured as a standard PVC
circuit and does not listen to video signals.
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If you set the Mode to RS366 , the circuit is put into an active listener mode;
it listens for video signals from premises devices.
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If you set the Mode to DBA , the circuit is configured to dynamically reassign
the timeslot.
The CBR module supports two types of dynamic bandwidth allocation (DBA):
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Structured voice DBA—Stored signaling bits are checked and bandwidth is
released when an on-hook (idle) condition is detected.
n
Structured data DBA—DSO payload bytes are checked and bandwidth is
released when an on-hook (idle) condition is detected.
For details about how DBA works, see “DS0 Signaling and Dynamic Bandwidth
Allocation” in Chapter 4. For details about configuring CBR virtual circuits for
DBA, see “Configuring CBR Virtual Circuits for DBA” later in this chapter.