Presentation on theme: "John Pietras 16 October 2008 Berlin Tracking Data Cross Support Transfer Service Status."— Presentation transcript:
John Pietras 16 October 2008 Berlin Tracking Data Cross Support Transfer Service Status
2 Tracking Data Cross Support Transfer Service Aimed at “real time” streaming tracking data –However, delayed complete delivery also supported Service goals –Transfer valid TDM content –Minimize bandwidth required
Header Metadata 1 Data 1 Metadata 2 Data 2 Metadata n Data n Header Metadata Metadata 2 DATA_START Record Tracking Data Record(s) Metadata Partition Data Partition(s) DataStop Partition Metadata Partition Data Partition DataStop Partiton Metadata Partition Data Partition Final Partition DATA_START Record Tracking Data Record(s) DATA_STOP record Metadata n DATA_START Record Tracking Data Record(s) DATA_STOP record. TD Operation TDM TDM Partitions Invocations Data n-1 Tracking Data Record(s) DATA_STOP record TRANSFER-DATA NOTIFY ‘metadata updated’ TRANSFER-DATA NOTIFY ‘data stopped’ NOTIFY ‘tdm header’ Header Partition NOTIFY ‘start time metadata’ NOTIFY ‘data stopped’ NOTIFY ‘metadata updated’ NOTIFY ‘data stopped’ TRANSFER-DATA NOTIFY ‘end of data’ Mapping TDM Segment to TD-CSTS Operations
4 Issue with Current Approach TDM parameter names are qualified by the metadata. E.g; –The link is identified in the Metadata –The parameter is named in the Data –If a spacecraft has 2 links (e.g., S and X band) and Transmit Frequency and Receive Frequency are being used concurrently, the metadata has to change for every pair of reported values
5 Possible Approaches Repeat metadata for each measurement pair –Fully supported by TDM specification –Higher bandwidth requirements – is this a problem? Modification to TDM –Modify TDM keywords E.g., allow multiple indexed PATHs to exist Let Data keywords reference the indexed PATHs –Allow partial Metadata respecification –Where to apply these modifications? Part of TDM specification? TD-CSTS-specific compression? Run separate TD-CSTS instances for each tracking PATH –Reasonable for separation of radiometric from meteorological data –Not so good for separate RF links
6 Fundamental Question How important is minimizing TD-CSTS bandwith?