3Com 3C63100-AC-C - PathBuilder S600..., Справочное руководство

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Application Module Overview 81
The emulated circuit connection from the CBR DSX port to a remote CBR DSX port
is accomplished by mapping DS1 circuits to Permanent Virtual Circuits. These
circuits will then be transmitted through the ATM network to the destination port.
For details on configuring the PVC, see “Configuring Virtual Circuits”” in
Chapter 5.
Cell Delay Variation is compensated for by the PathBuilder S600 through an
adaptive receive buffer. This buffer can provide consistent synchronous delivery of
DS1 service by building in delay in excess of ATM cell delay and outputting from a
receive buffer. You can configure the adaptive delay.
Dynamic Bandwidth Allocation Through dynamic bandwidth allocation, the
CBR DSX module can de-activate the CBR PVC and free up network access
bandwidth for other uses. See “Dynamic Bandwidth Allocation (DS0 Signaling)”,
later in this chapter, for details.
CBR DSX Module Standards Support Table 22 lists the ATM standards
supported by the CBR DSX module.
CBR E1 Module
The CBR E1 module features four or eight E1 ports for transit over an ATM
network. It provides a circuit emulator service mapped to ATM cells. The E1 inputs
can be either single or multi-frame using HDB3 line coding. The received frame
can be tunneled through the ATM network using E1 unstructured mode or broken
up into its DS0 and ABCD signaling components using E1 structured mode. The
structured mode allows DS0 mid span drop and insert or grooming.
The structured and unstructured mode comply with ATM Forum
AF-SAA-0032.000. This service maps the E1 service through AAL1 adaptation
layer over a CBR virtual channel connection (VCC). The VCC is established as a
permanent virtual circuit (PVC) and mapped from the PathBuilder S600s ATM port
to either another PathBuilder S600 or an ATM Forum circuit emulation compliant
device.
Network Cell Delay Variation is compensated for by the PathBuilder S600 through
an adaptive receive buffer. This buffer can provide consistent synchronous delivery
of E1 service by building in delay in excess of ATM cell delay and outputting from a
receive buffer. The adaptive delay is configurable.
CBR E1 Module Standards Support Table 23 lists the standards supported by
the CBR E1 module.
Table 22 CBR DSX Module ATM Forum/ANSI/ITU-T Supported Standards
AF-SAA-0032.000 ATM Forum Circuit Emulation Service (CES)
ANSI T1.630/ITU-T I.363 AAL1 Unstructured Data Transfer Mode
Table 23 CBR E1 Module ATM Forum/ANSI/ITU-T Supported Standards
AF-SAA-0032.000 ATM Forum Circuit Emulation Service (CES)
ANSI T1.630/ITU-T I.363 AAL1 Unstructured Data Transfer Mode