8.4. ATM QoS Policy Command Reference

This command creates a text description stored in the configuration file for a configuration context.

The no form of this command removes any description string from the context.

This command is used to configure an ATM traffic descriptor profile as per ATM Forum Traffic Management Specification Version 4.1.

Traffic descriptor profiles are used to:

The default traffic descriptor is preconfigured and non-modifiable. It cannot be deleted. All other traffic descriptor profiles must be explicitly created before use. The create keyword must follow each new profile configuration.

Any changes made to the existing profile, using any of the sub-commands, are applied immediately to all objects where this profile is applied (a small traffic interruption in data traffic will occur during the data plane reprogramming with the newly modified profile).

When many changes are required on a profile, it is recommended that the profile be copied to a work area profile ID. That work-in-progress profile can be modified until complete and then written over the original profile-id. Use the config>qos>copy command to maintain profiles in this manner.

The weight assigned to each non-shaped PVCC in the Deficit Round Robin Scheduler depends on the service category and traffic rates (see the traffic command for more details).

The no form of the command deletes a given traffic profile. The profile to be deleted must not be associated with any object (for example a SAP). If this condition is not met, the command will return an error.

This command is used to specify the type of ATM traffic descriptor profile as per ATM Forum Traffic Management Specification Version 4.1.

This command determines whether ingress traffic is policed. Policing is valid for CBR, rt-VBR, nrt-VBR, and UBR. This policing is cell-based.

This command is used to configure an ATM service category attribute of an ATM traffic descriptor profile.

This command determines whether egress shaping should occur. Shaping is only applied in the egress direction.

This command is used to configure traffic attributes of an ATM traffic profile as per ATM Forum Traffic Management Specification Version 4.1.

The traffic parameters of a traffic descriptor that are configurable depend on the service category of this traffic descriptor profile. (See the service-category command.)

Table 58 defines which traffic descriptor parameters are applicable for what service category and what the configuration rules are between the parameters. “Y” indicates that the parameter can be configured for a given service category and will be defaulted if not provided, and an “N/A” indicates that the parameter cannot be configured for a given service category (an error will be returned). If an applicable parameter is not specified, the current value will be preserved.

When a traffic descriptor profile is used to define egress scheduling, the following describes how traffic rates are used to derive scheduling weight:

The scheduling weight applies only to unshaped nrt-VBR and UBR. The scheduling weight is a value from 1 to 8. The scheduling weight is determined by the SIR value for nrt-VBR, and by the MIR value for UBR. The conversion from SIR/MIR to weight is as follows:

Everything above 1920K will be assigned a weight of 8.

Since the 7705 SAR operates in cells/second with one cell granularity, PIR and SIR values programmed need to be converted to cells/second. When converting values to be used for the scheduler, the result is rounded up to the next cell when required by conversion.

When any of SIR, PIR, or MIR is greater than the physical maximum port/channel capacity for a given PVCC, then the maximum physical port/channel capacity is used in bandwidth accumulation and when configuring the hardware for that PVCC.

Hardware-enforceable MBS is in the inclusive range of 3 to 256 000 cells on all 7705 SAR ATM-capable adapter cards. Assigning an atm-td-profile with an MBS value outside of this range to a SAP is blocked. As well, once an atm-td-profile is assigned to a SAP, the CLI will block any change of the MBS value to a value outside of this range.

The no form of the command restores traffic parameters to their defaults for a given service category.