Configuring a Bridge Tunnel and Displaying Status Information

Use the ATM Bridge Tunnel Status and Configuration window to:

  • Display status information about the ATM bridge tunnel

  • Display information about the virtual circuits used by the ATM logical interface

  • Display ATM bridge tunnel configuration information

  • Configure the ATM bridge tunnel

The ATM port (physical interface) on the VNswitch supports as many as 16 logical ATM interfaces.  Each logical interface can be configured as either an ATM LAN Emulation Client or a bridge tunnel.

For additional information,  refer to ATM Logical Interfaces Established at Startup.

Configuring an ATM Bridge Tunnel

A bridge tunnel is a permanent virtual channel established to provide a simple point-to-point connection between two devices through an ATM network. A bridge tunnel is established over a Permanent Virtual Circuit (PVC). Each bridge tunnel requires a separate PVC.

Unlike an ATM LAN Emulation Client (LEC), a bridge tunnel does not require those elements (LAN Emulation Server, LAN Emulation Configuration Server, and Broadcast and Unknown Server, for example) otherwise necessary to establish an emulated LAN.

Procedure:

Step Action
1 Select the MAC type, either Ethernet or FDDI.

Note:   When you change to a different MAC type, you must restart the switch before the new configuration takes effect.

2 To enable or disable this ATM logical interface, select enable or disable from the drop-down box next to the Interface field.
3 Set the VPI.

The VPI is the Virtual Path Identifier assigned to the PVC.  The VPI is automatically set to 0 for the current release.  

4 Enter the VCI.

The VCI is the Virtual Circuit Identifier assigned to the  PVC. By default, the VCI is set to 62.  Any value from 62 through 1022 is allowed.

5 Ensure that the device at the opposite end of the bridge tunnel is configured to match this configuration.  The other device could be another VNswitch, a DIGITAL GIGAswitch/ATM, or another vendor's ATM switch.   Refer to the appropriate documentation provided by the manufacturer of that device for configuration instructions.

Configuring an ATM LAN Emulation Client (LEC)

Warning: Changing the bridge tunnel to an LEC erases the current bridge tunnel configuration.

To configure the ATM logical interface as a LAN Emulation Client (LEC), click Change to LEC, then click the Help button within the ATM LEC Configuration and Status application window.

Field Descriptions

Status
MAC Type Indicates the type of bridge tunnel configured on the interface: either Ethernet or FDDI.
VPI Virtual Path Identifier associated with the virtual circuit used by the bridge tunnel.
Quality of Service Indicates the Quality of Service class of the virtual circuit used by the bridge tunnel:
  • Class 1 supports Constant Bit Rate Video
  • Class 2 supports Variable Bit Rate Video
  • Class 3 supports Connection-oriented data transfer
  • Class 4 supports Connectionless data transfer
BT Status Current status of the bridge tunnel, either Up or Down.
VCI Virtual Circuit Identifier associated with the virtual circuit used by the bridge tunnel.
LAN FCS Indicates whether a Frame Check Sequence (FCS) checksum is added to the end of each frame that is transmitted.
Virtual Circuits
Ifc Logical interface number associated with the interface. 
VPI Lists the Virtual Path Identifier associated with the interfaces listed in the Ifc column.
VCI Lists the Virtual Circuit Identifers (VCIs) associated with the interfaces listed in the Ifc column.
Type Indicates the type of virtual circuit used by the bridge tunnel.  Examples are ILMI VC, Signalling VC, LE Control VC, and so forth.
S/PVC Indicates whether the circuit is a switched virtual circuit (SVC) or a permanent virtual circuit (PVC).
ATM Address ATM address of the corresponding logical interface listed in the Ifc column.
ATM Bridge Tunnel Configuration
MAC Type Specifies MAC frame types transported through the bridge tunnel. When set to Ethernet, this field idicates the interface is configured as an Ethenet bridge tunnel; when set to FDDI, this field indicates the interface is configured as an FDDI bridge tunnel.
Interface Specifies whether the interface is enabled or disabled.
VPI Specifies the Virtual Path Identifier assigned to the PVC over which the bridge tunnel operates. The VPI is always 0.
VCI (62-1022) Specifies the Virtual Circuit Identifier associated witht the PVC over which the bridge tunnel operates.