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Space-based DTN

Space-based DTN. Low Earth Orbit Results NASA Plans CCSDS Plans Will Ivancic, william.d.ivancic@nasa.gov http://roland.grc.nasa.gov/~ivancic/papers_presentations/2008/IETF73_IRTF_DTN.ppt. Secure Autonomous Integrated Controller for Distributed Sensor Webs.

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Space-based DTN

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  1. Space-based DTN Low Earth Orbit Results NASA Plans CCSDS Plans Will Ivancic, william.d.ivancic@nasa.gov http://roland.grc.nasa.gov/~ivancic/papers_presentations/2008/IETF73_IRTF_DTN.ppt

  2. Secure Autonomous Integrated Controller for Distributed Sensor Webs VMOC negotiates for Space Assets Network Control Center Configures Spacecraft via VMOC VMOC negotiates for ground station services Stored data transferred to ground (Large file transfer over multiple ground stations) Space Sensor acquires data (e.g. image) 7 6 3 5 2 2 4 Stored data transferred to ground 4 Network Control Center Configures Ground Assets 3 VMOC negotiates for ground station services 4 1 Seismic Sensor alerts VMOC Network Control Center Configures Ground Assets Sensor 4 VMOC NOC NOC NOC

  3. DTN Test Plan • Goal • Demonstrate DTN Bundle Transfer from UK-DMC to SSTL Ground Station • Demonstrate that DTN code and general SSTL code can coexist without affecting normal SSTL Operations • Configuration • UK-DMC acquired a150 Mbyte image Cape of Good Hope, South Africa using the DTN SSDR code. DTN bundling code default set to 80 Mbytes for proactive fragmentation • Tests • Basic file download using existing technique (GRC implementation of Saratoga version 0) • Same file downloaded but treated as single bundle (DTN) • Same file download but using DTN proactive fragmentation with 80 Mbytes preconfigured fragments. • SSTL used their Workstation and SSTL implementation of Saratoga version 0

  4. UK-DMC Implementation Only Bundling and Forwarding Implemented Full DTN Protocol Implemented Surrey Satellite Tech Ltd (SSTL) Saratoga Client  Test 4

  5. Bundles on UK-DMC Payload DTN Metadata Proactive Fragmentation Metadata - N Proactive Fragmentation Metadata - 0 70 MB  150 Mbytes 80 MB Not to Scale  70 bytes N=2  70 - 80 bytes  70 - 80 bytes  70 - 80 bytes

  6. www.dmcii.com The Cape of Good Hope and False Bay. False colours – red is vegetation. Taken by UK-DMC satellite on the morning of Wednesday, 27 August 2008. Downloaded using bundling over Saratoga, with proactive fragmentation. Fragments assembled at NASA Glenn, then postprocessed at SSTL. First sensor imagery delivered by bundles from space. Palm Island Resort, Dubai, 14 Dec 2003 (UK-DMC)

  7. Checksums were very useful • We implemented manual MD5 checksums over the payload • Greatly aided in debugging • Identified errors in our Saratoga transport protocol implementation • Allowed us to prove data was transmitted correctly received without errors • Used for full bundle and reconstituted bundle fragments checking • 150 Mbytes is a bit to much to manually check • Checksums can take significant time relative to a satellite pass, thus, we made it a command option • Apparently sometimes SSTL dumps an image and takes another during the same pass (8 – 12 minutes).

  8. NASA DTN Fight Readiness by 2011 • Multi-Center Program • JPL, APL, MSFC, JSC, GRC, MSFC, University of Colorado • Multiple Flight Implementations of RFC 5050 and LTP • JPL, Applied Physics Lab, Goddard Space Flight Center • Flight Tests • Deep Impact (JPL) • ISS (Bioserve – University of Colorado) • Desire to get Operations people involved • Multi-Center DTN Engineering Testbed (DEN) • Strawman Scenarios (Low Earth Orbit, Lunar, Deep Space such as Mars) • Technology Development / Research • Network Management • Also work with DARPA (BBN) • GRC plans to work with DTNRG • Naming and Routing • Security Issues

  9. Multi-Center DTN Testbed GRC plans to put DTN machines on the OpenNet

  10. Consultative Committee for Space Data Systems(CCSDS)

  11. Organization • CCSDS consists of Member Agencies, Observer Agencies, Associates and Liaisons. • A CCSDS Member Agency is a governmental or quasi-governmental organization • Only one agency representing a given country or multinational organization may participate as a Member Agency of the CCSDS. • Each CCSDS Agency must formally appoint its delegates to the CCSDS technical Working Groups which that Agency supports Opinion/Observation CCSDS patterns itself partially after ITU and partially after IETF

  12. Organization

  13. CCSDS Colors / Books

  14. Space Internetworking Services (SIS) - DTN • Goal • Determine whether or not “Delay-Tolerant Networking” as specified in RFC5050 is a feasible solution for a store-and-forward networking protocol for space environments where data relay is likely. • If RFC5050 is lacking in certain specific capabilities, this working group may define extensions to RFC5050 to address these needs. • If RFC5050 is not suitable, attempt to define an alternate protocol that meets the needs of the space community. • Use LTP as Transport Protocol • Additional protocols are required in order to provide a complete, working network. The working group will also produce the following documents: • A Blue Book covering DTN naming and addressing conventions to be used. • A Blue Book specifying one or more routing protocol(s) to be used by DTN. • A Magenta Book describing DTN use cases and advice for applications designers and mission planners. Great Desire to use RFC 5050 as is in order to speed standardization and maintain interoperability with Earth terrestrial DTNs

  15. SIS-DTN Schedule (Proposed) • Spring 2008 CCSDS Meetings Concept paper for discussion. • Fall 2008 CCSDS Meetings • Green-1 book describing rationale / scenarios / use cases used to evaluate • Red-1 protocols. • Spring 2009 CCSDS Meetings • Green-2 Book. Goal is to submit this into the publication process by summer 2009. • Red-1 book describing CCSDS Delay-Tolerant Networking protocol • Red-1 book describing reliable hop-by-hop protocol. • Begin initial implementation development as needed. • Fall 2009 CCSDS Meetings • Final Green Book Approved describing rationale / scenarios / use cases used to evaluate. • Magenta-1 book on advice to application designers and mission planners. • Red-1 book describing naming / addressing conventions. • Begin initial interoperability testing of implementations. • Spring 2010 CCSDS Meetings • Red-2 Book for CCSDS Delay-Tolerant Networking protocol • Red-2 Book for reliable hop-by-hop protocol.Red-1 books describing DTN routing protocol. • Fall 2010 CCSDS Meetings • Magenta-2 book on advice to application designers and mission planners. • Second round interoperability testing of DTN and reliable hop-by-hop protocols. • Spring 2011 CCSDS Meetings • Blue-1 Recommendations (DTN and reliable hop-by-hop) • Red-2 books describing naming / addressing conventions • Red-2 books describing DTN routing protocol. • Fall 2011 CCSDS Meetings • Final Magenta book on advice to application designers and mission planners. • Spring 2012 CCSDS Meetings • Blue-1 Recommendation for naming / addressing • Blue-1 Recommendation for routing protocol(s).

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