1 PSAMP Protocol Specifications PSAMP IETF-58 November 11, 2003 Benoit Claise Juergen Quittek

222 PWE3 Architecture IETF-55 Table of Content 2. Introduction 3. Terminology 4. Relationship between PSAMP and IPFIX 4.1 IPFIX Overview 4.2 IPFIX and PSAMP Differences and Similarities Export Point of View Information Model Point of View 5. Using IPFIX for PSAMP 5.1 High Level View of the Integration 5.2 Partial or Entire IPFIX Protocol Specifications Support

333 PWE3 Architecture IETF-55 Table of Content 6. PSAMP Requirements versus the IPFIX Solution 6.1 IPFIX Solution for the PSAMP Requirements 7. Low Level View of the Integration 7.1 Sampling Case, PSAMP Base Level of Functionality Example 7.2 Sampling Case Example 7.3 Filtering Case Example 8. Security Considerations

444 PWE3 Architecture IETF-55 IPFIX latest news Vendor Identifier Information Element Those present agreed that text "compressed VI qualified" from the draft be copied directly into the IPFIX protocol draft. TCP versus SCTP A show of hands by in the meeting showed otherwise, with more favoring SCTP than TCP. However, many did not express an opinion. This issue will be taken to the mailing list to test the meeting consensus.

555 PWE3 Architecture IETF-55 IPFIX and PSAMP Differences and Similarities Export Point of view PSAMP doesn’t have the notion of flow IPFIX will not distinguish a flow record composed of several packets aggregated together, from a flow record composed of a single packet As a conclusion, the PSAMP export can be seen as special IPFIX flow record containing information about a single packet. Note: the IPFIX terminology is kept unchanged

666 PWE3 Architecture IETF-55 IPFIX and PSAMP Differences and Similarities Information Model Point of view As the templates are flexible, IPFIX will not distinguish what it exports IPFIX source IP address, destination IP address, ToS, etc. PSAMP the packet fragment (base level of functionality) "Recommended Contents for Packet Reports“ framework draft: the PSAMP reporting process SHOULD also report fields relating to the protocols used in the packets, to the packet treatment and to the selection state associated with the packet. Both information models are overlapping PSAMP information model will augment the IPFIX information model

777 PWE3 Architecture IETF-55 Templates and Options Templates Templates and Flow Data Records Templates: supply information about which data types are exported Flow Data Records: the values of the data types defined in the templates Options Templates and Options Data Records Options Templates: supply information about the Metering Process configuration or Metering Process specific data Options Data Records: the values of the data types defined in the Options Templates

888 PWE3 Architecture IETF-55 Using IPFIX for PSAMP Data FlowSet/ Flow Data Record or Options Data Record Template FlowSetTemplate Record/ Options Template Options Template Record / FlowSet Template Record Data Record Full IPFIX implementation is required for PSAMP

999 PWE3 Architecture IETF-55 Sampling Case Example PSAMP Base Level of Functionality Packet Report: Packet Interpretation: Template FlowSet: Template Record (SEQUENCE_NUMBER, PACKET_SAMPLE, SELECTOR_ID) Options Template FlowSet: Options Template Record (SELECTOR_ID, SAMPLING_ALGO, SAMPLING PARAM, OBSERVATION POINT) Data FlowSet: Flow Data Record (SEQUENCE_NUMBER #, PACKET_SAMPLE xxx, SELECTOR_ID 1) Data FlowSet: Options Data Record (SELECTOR_ID 1, systematic sampling, 1/100, ifIndex 3)

10 PWE3 Architecture IETF-55 Sampling Case Example PSAMP Base Level of Functionality The packet reports must contain (framework) the SEQUENCE-NUMBER, PACKET-SAMPLE Template FlowSet defines a Template Record composed of SEQUENCE- NUMBER, PACKET-SAMPLE and SELECTOR-ID. The report interpretation must contain (framework) the SAMPLING- ALGORITHM, SAMPLING-PARAMETER1, SAMPLING- PARAMETER2,, OBSERVATION POINT, etc… The Options Template FlowSet defines a Options Template Record composed of SELECTOR-ID, SAMPLING-ALGORITHM, SAMPLING-PARAMETERS. Finally the Data FlowSet is used to export the Flow Data Record(s) containing the real values of SEQUENCE-NUMBER, PACKET-SAMPLE and SELECTOR-ID. The Data FlowSet is also used to export the Options Data Record(s) containing the real values of SELECTOR-ID, SAMPLING-ALGORITHM, SAMPLING- PARAMETERS.

11 PWE3 Architecture IETF-55 Sampling Case Example Packet Report: Packet Interpretation: Template FlowSet: Template Record (SEQUENCE_NUMBER, PACKET_SAMPLE, DEST_AS, SELECTOR_ID) Options Template FlowSet: Options Template Record (SELECTOR_ID, SAMPLING_ALGO, SAMPLING PARAM, OBSERVATION POINT) Data FlowSet: Options Data Record (SELECTOR_ID 1, systematic sampling, 1/100, ifIndex 3) Data FlowSet: Flow Data Record (SEQUENCE_NUMBER #, PACKET_SAMPLE xxx, DEST_AS d, SELECTOR_ID 1)

12 PWE3 Architecture IETF-55 PSAMP Requirements versus the IPFIX Solution Transparency: “allow transparent interpretation of measurements as communicated by PSAMP reporting, without any need to obtain additional information concerning the observed packet stream.” This requirement is addressed by exporting the Selector ID in every Flow Data Records (packet report) and in the Options Data Records

13 PWE3 Architecture IETF-55 PSAMP Requirements versus the IPFIX Solution Robustness to Information Loss: “allow robust interpretation of measurements with respect to reports missing due to data loss, e.g. in transport, or within the measurement, reporting or exporting processes. Inclusion in reporting of information that enables the accuracy of measurements to be determined. An Options Templates MUST be sent on regular basis. This Options Template contains for example the total number of packet report exported from the PSAMP device, the total number of packet observed, etc... Thus the Collector can compare the number of packet report received per selector ID with the number actually metered and/or sent. In case of discrepancy, a new sampling rate could be computed.

14 PWE3 Architecture IETF-55 Open Issue Terminology section cut/paste the IPFIX protocol spec. section when finalized. Need the IANA consideration section in IPFIX Doublecheck the examples with the information model data type Must clearly define the sampling examples Must have a filtering example Sequential order of sampling/filtering. How to report the order to the collector? Describe the packet fragment encoding with the variable length data type Input sequence discrepancy between all the drafts Need some text review/polishing Any others?

15 PWE3 Architecture IETF-55 Open Issue Thank you