Cisco BPX 8600 Series, Руководство по установке и настройке

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Cisco BPX 8600 Series Installation and Configuration
Release 9.3.0, Part Number 78-10674-01 Rev. D0, July 2001
Chapter 23 Configuring BXM Virtual Switch Interfaces
Class of Service Templates and Qbins
2.
VSI messages (from Master VSI controller or other slave VSI card) are forwarded to the standby
slave VSI card by the active slave VSI card.
Operation 2 is normal data transferring, which occurs after both cards are in-sync.
3. When the standby slave VSI card starts up, it retrieves all VSI messages from the active slave VSI
card and processes these messages.
Operation 3 is initial data transferring, which occurs when the standby card first starts up.
The data transfer from the active card to the standby card should not affect the performance of the active
card. Therefore, the standby card takes most actions and simplifies the operations in the active card.
The standby card drives the data transferring and performs the synchronization. The active card
functions just forward VSI messages and respond to the standby card requests.
Class of Service Templates and Qbins
Class of Service Templates (COS Templates) provide a means of mapping a set of standard connection
protocol parameters to “extended” platform specific parameters. Full Quality of Service (QoS) implies
that each VC is served through one of a number of Class of Service buffers (Qbins) which are
differentiated by their QoS characteristics.
A qbin template defines a default configuration for the set of qbins for a logical interface. When you
assign a template to an interface, the corresponding default qbin configuration is copied to this
interface’s qbin configuration and becomes the current qbin configuration for this interface.
Qbin templates deal only with qbins that are available to VSI partitions, which are 10 through 15. Qbins
10 through 15 are used by VSI on interfaces configured as trunks or ports. The rest of the qbins are
reserved and configured by Automatic Routing Management.
How Service Templates Work
The service class template provide a means of mapping a set of extended parameters, which are
generally platform specific, based on the set of standard ATM parameters passed to the VSI slave during
connection setup.
A set of service templates is stored in each switch (such as BPX) and downloaded to the service modules
(such as BXMs) as needed.
The service templates contains two classes of data:
• Parameters necessary to establish a connection (that is, per VC), including entries such as UPC
actions, various bandwidth related items, per VC thresholds, and so on.
•
Parameters necessary to configure the associated class of service buffers (qbins) that provide QoS
support.
The general types of parameters passed from a VSI Master to a Slave include:
• A service type identifier
•
QOS parameters (CLR, CTD, CDV)
• Bandwidth parameters (such as PCR, MCR)
• Other ATM Forum Traffic Management 4.0 parameters
Each VC added by a VSI master is assigned to a specific service class by means of a 32-bit service type
identifier. Current identifiers are for:
• ATM Forum service types