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Dear all, We need a way of specifying the accuracy of our reported information, as PSAMP frameworks specifies: "the Report Stream must include information that enables the accuracy of measurements to be determined.". Here is some proposed text. Section 7.4.4 Accuracy Report Interpretation In order for the Collecting Process to determine the inherent accuracy of the reported quantities (for example timestamps), the PSAMP Device SHOULD send an Accuracy Report Interpretation. The Accuracy Report Interpretation MUST be exported by an Option Template Record with a double scope that contains the TemplateId [PSAMP-INFO] and the Information Element for which the accuracy is required. The accuracy SHOULD be reported either with the fixedAccuracy Information Element [PSAMP-INFO], or with the proportionalAccuracy Information Element [PSAMP-INFO]. Accuracy Report Interpretation using the fixedAccuracy Information Element Scope: TemplateId InformationElementId Non-scope: fixedAccuracy Accuracy Report Interpretation using the proportionalAccuracy Information Element Scope: TemplateId InformationElementId Non-scope: proportionalAccuracy For example, the accuracy of an Information Element whose Abstract Data Type is dateTimeMilliSeconds [IPFIX-INFO], for which the unit is specified as milliseconds, can be specified with the fixedAccuracy Information Element with the milliseconds units. In this case, the accuracy is the Information Element value +/- the value reported in the fixedAccuracy. For example, the accuracy of an Information Element to estimate the accuracy of a sampled flow, for which the unit would be specified in octets, can be specified with the proportionalAccuracy Information Element with the octet units. In this case, the accuracy is the Information Element value +/- the value reported in the proportionalAccuracy time Information Element value. Alternatively to reporting either the fixedAccuracy Information Element or the proportionalAccuracy Information Element in the Accuracy Report Interpretation, both Information Elements MAY be present. This scenario could help in more complex situations where the system clock drifts, on the top of having its own accuracy, during the duration of a measurement. If the accuracy of a reported quantity changes on the Metering Process, a new Accuracy Report Interpretation MUST be generated. The Collecting Process MUST keep the accuracy of the latest Accuracy Report Interpretation. Example 1 (to be developed) Records (using template 12): 1. Scope: TemplateId = 5, InformationElementId = 152 Non-scope: fixedAccuracy = 2 => we have a accuracy of +/- 2ms) Example 2 (to be developed): 1. Scope: TemplateId = 5, InformationElementId = 152 Non-scope: proportionalAccuracy = 0.005 => we had an accuracy of +/- 0.5% --------------------- For the PSAMP information model: fixedAccuracy Description: proportionalAccuracy Description:informationElementID Description:Regards, Benoit. |