Glossary

meter

meter A device that measures the rate of a traffic stream selected by a classifier. The instantaneous state of this process can be used to affect the operation of a marker, shaper, or policer.

per hop behavior (PHB) The externally observable forwarding treatment applied at

aDS-compliant node to a collection of packets with the same DSCP.

policer A device that as part of shaping discards (drops) packets within a traffic stream, in accordance with the state of a corresponding meter enforcing a traffic profile.

policy block In the context of an HP-UX IPQoS configuration file, defines a specific policy to apply to traffic which matches any filters associated with the policy.

Quality of Service (QoS) A set of service requirements to be met by the network while transporting a flow. Implies a mechanism to deliver better than best-effort service to network traffic.

service level agreement (SLA) A service contract between a customer and a service provider that specifies the forwarding service the customer is to receive. It can include traffic conditioning rules.

service provisioning policy A policy that defines how traffic conditioners are configured on DS boundary nodes, and how traffic streams are mapped to DS behavior aggregates to achieve a range of services.

shaper A device that delays packets within a traffic stream to cause it to conform to some defined traffic profile, usually to reduce load peaks.

traffic classification The process where packets in a traffic stream are filtered into distinct classes (groups) based on the content of a part of the packet header.

traffic conditioning The process where packets in a traffic stream are subject to control functions including metering, marking, policing and shaping.

traffic shaper See shaper.

traffic profile A description of the temporal properties of a traffic stream. For example, rate and burst size.

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Glossary