Overview: How Vsi Works; Virtual Interfaces And Qbins - Cisco BPX-BXM-155-8DX Installation And Configuration Manual

Overview: How VSI Works

Overview: How VSI Works
This section provides detailed reference to virtual interfaces, service templates, and qbins.
For information on configuring SES PNNI controllers to work with BPX switches, see the Cisco SES
PNNI Controller Software Configuration Guide.
For information on configuring MPLS controllers to work with BPX switches, see the Cisco MPLS
Controller Software Configuration Guide.
Refer to Cisco WAN Switching Command Reference for details about the commands mentioned here for
both PNNI and MPLS controllers. Refer to Release Notes for supported features.

Virtual Interfaces and Qbins

The BXM has 31 virtual interfaces that provide a number of resources including qbin buffering
capability. One virtual interface is assigned to each logical trunk (physical or virtual) when the trunk is
enabled. (See Figure 23-1.)
Each virtual interface has 16 qbins assigned to it. Qbins 0-9 are used for Autoroute and 10 through 15
are available for use by a VSI enabled on the virtual interface. (In Release 9.1, only qbin 10 was used.)
The qbins 10 through 15 support class of service (CoS) templates on the BPX.
You may enable a virtual switch interface on a port, trunk, or virtual trunk. The virtual switch interface
is assigned the resources of the associated virtual interface.
With virtual trunking, a physical trunk can comprise a number of logical trunks called virtual trunks.
Each of these virtual trunks (equivalent to a virtual interface) is assigned the resources of one of the 31
virtual interfaces on a BXM (see Figure 23-1).
Cisco BPX 8600 Series Installation and Configuration
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Chapter 23 Configuring BXM Virtual Switch Interfaces
Release 9.3.0, Part Number 78-10674-01 Rev. D0, July 2001