Cisco Systems OL-7396-01 Manual De Usuario
7-2
ATM Switch Router Software Configuration Guide
OL-7396-01
Chapter 7
Configuring Virtual Connections
Characteristics and Types of Virtual Connections
•
Characteristics and Types of Virtual Connections
This section lists the various virtual connections (VC) types in
Configuring Virtual Channel Connections
This section describes configuring virtual channel connections (VCCs) on the ATM switch router.
A VCC is established as a bidirectional facility to transfer ATM traffic between two ATM layer users.
A VCC is established as a bidirectional facility to transfer ATM traffic between two ATM layer users.
shows an example VCC between ATM user A and user D.
An end-to-end VCC, as shown in
between user A and user D, has two parts:
•
Virtual channel links, labelled VCL. These are the interconnections between switches, either
directly or through VP tunnels.
directly or through VP tunnels.
•
Internal connections, shown by the dotted line in the switch. These connections are also sometimes
called cross-connections or cross-connects.
called cross-connections or cross-connects.
The common endpoint between an internal connection and a link occurs at the switch interface.
The endpoint of the internal connection is also referred to as a connection leg or half-leg.
A cross-connect connects two legs together.
The endpoint of the internal connection is also referred to as a connection leg or half-leg.
A cross-connect connects two legs together.
Figure 7-1
VCC Example
Table 7-1
Supported VC Types
Connection
Point-to-
Point
Point
Point-to-
Multipoint
Multipoint
Transit
Terminate
Permanent virtual channel link (PVCL)
x
x
—
—
Permanent virtual path link (PVPL)
x
x
—
—
Permanent virtual channel (PVC)
x
x
x
x
Permanent virtual path (PVP)
x
x
x
—
Soft permanent virtual channel (Soft PVC)
x
x
x
x
Soft permanent virtual path (Soft PVP)
x
—
x
—
Switched virtual channel (SVC)
x
x
x
x
Switched virtual path (SVP)
x
x
x
—
User A
VCC
VCL
VPI/VCI = 0/50
IF# = 3/0/1
VCL
VCL
VPI/VCI = 50/255
IF# = 0/0/1
IF# = 0/0/1
IF# = 0/0/0
VPI/VCI = 2/100
IF# = 3/0/2
Switch B
Switch C
User D
H6294