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ATM Switch Router Software Configuration Guide
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Chapter19 Configuring Circuit Emulation Services
Configuring T1/E1 Structured (n x 64) Circuit Emulation Services
Dst: atm addr 47.0091.8100.0000.00e0.4fac.b401.4000.0c81.8030.00
Configuring a Soft PVC for Structured CES with CAS Enabled
Since the CES T1/E1 port adapter emulates CBR services over ATM networks, it must be able to support
channel-associated signalling (CAS) information that is introduced into structured CES circuits by PBXs
and TDMs. An optional CAS feature for the CES T1/E1 port adapter meets this requirement.
CAS information carried in a CBR bit stream can be configured with a CES module, as follows:
The optional CAS feature is not enabled (the default state). For information about configuring a
soft PVC for structured CES without CAS enabled, see the Configuring a Soft PVC for Structured
CES, page 19-28.
The optional CAS feature is enabled, but without the optional, Cisco-proprietary on-hook detection
feature enabled. This option is described in the following procedure.
Both the optional CAS and on-hook detection features are enabled. For information about
configuring a soft permanent virtual channel (soft PVC) for structured CES with both CAS and
on-hook detection enabled, see Configuring a Soft PVC for Structured CES with CAS and On-Hook
Detection Enabled, page 19-37.
Note For a detailed description of CAS operation and the on-hook detection feature, refer to the circ uit
emulation services topic in the Guide to ATM Technology.
This section describes how to configure a softPVC for structured CES with channel-associated
signalling (CAS) enabled.
Note Typically you will configure a softPVC between CES modules anywhere in your network. For
simplicity, this example and the accompanying procedure describe how to create a soft PVC between
modules in the same ATM switch router chassis.
The following procedure is based on the following assumptions:
The source (active) side of the softPVC (CBR-PVC-A) remains as previously configured.
The destination (passive) side of the soft PVC (CBR-PVC-B) remains as previously configured.
Four time slots (DS0 channels) remain as previously configured for the softPVC:
For circuit CBR-PVC-A: DS0 channels 1 to 3 and 7 are used on port CBR3/0/0.
For circuit CBR-PVC-B: DS0 channels 10 to 13 are used on port CBR3/0/3.
CAS is enabled for the circuit.
The signalling mode for the T1 CBR ports is set to “robbedbit.”
Figure 19-6 shows a softPVC configured for structured CES with CAS enabled.