ForeRunner
ATM Switch Network Configuration Manual
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Configuring PVCs
Co
nfigu
ri
ng PVCs
1.4 Virtual Channels
Virtual channels “ride” inside of virtual paths. The combination of the two specifies a virtual
connection. On a switch fabric, each virtual channel switches cells with a specific VPI and VCI
received on a specific port to another port with a new VPI and a new VCI. Unlike through
paths, which carry one or more VCCs, virtual channels describe a single virtual connection
between two endpoints.
Figure 1.8 -
An Example of a Virtual Channel
Six parameters are needed to define a virtual channel: input port, input VPI, input VCI, out-
put port, output VPI, and output VCI. Virtual channels are represented by the following nota-
tion:
<iport> <ivpi> <ivci> <oport> <ovpi> <ovci>
Virtual channels switch cells using both the VPI and VCI values. Both the VPI and VCI values
may change when a cell is switched via a virtual channel. For example, the virtual channel
C2|1|20 -> D2|9|25 switches cells received on port C2 with VPI: 1 and VCI: 20 such that they
are transmitted out port D2 with VPI: 9 and VCI: 25.
cell
VPI: A, VCI: B
VPI: X, VCI: Y
cell
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Summary of Contents for forerunner series
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Page 16: ...TOC 10 ForeRunner ATM Switch Network Configuration Manual Table of Contents ...
Page 20: ...LOF 4 ForeRunner ATM Switch Network Configuration Manual List of Figures ...
Page 22: ...LOT 2 ForeRunner ATM Switch Network Configuration Manual List of Tables ...
Page 30: ...viii ForeRunner ATM Switch Network Configuration Manual Preface ...
Page 144: ...3 58 ForeRunner ATM Switch Network Configuration Manual Configuring an Emulated LAN ...
Page 180: ...6 12 ForeRunner ATM Switch Network Configuration Manual ATM Forum PNNI ...
Page 220: ...9 6 ForeRunner ATM Switch Network Configuration Manual Configuring Timing ...
Page 300: ...D 24 ForeRunner ATM Switch Network Configuration Manual Configuring FramePlus Modules ...
Page 308: ...Acronyms 8 ForeRunner ATM Switch Network Configuration Manual Acronyms ...
Page 346: ...Glossary 38 ForeRunner ATM Switch Network Configuration Manual Glossary ...
Page 352: ...Index 6 ForeRunner ATM Switch Network Configuration Manual Index ...