Download presentation
Presentation is loading. Please wait.
Published byLouisa Johns Modified over 9 years ago
1
Mars BOF Meeting Report Colorado January 2007 Chris Taylor
2
Meeting Attendance list Dai StantonKeltik/Estecdstanton@keltik.co.uk Mathew CosbyQinetiq/BNSCmscosby@qinetiq.com Bob DurstMitre/NASAdurst@mitre.org Keith ScottMitre/NASAkscott@mitre.org Dave IsraelGSFC/NASAdave.israel@nasa.gov Howard WeissSparte/JPL/NASAhsw@sparta.com Wallace TaiJPL/NASAWallace.s.tai@jpl.nasa Chad EdwardsJPL/NASAchad.edwards@jpl.nasa.gov Greg KazzJPL/NASAgreg.j.kazz@jpl.nasa.gov Mike MckayEsoc/ESAmike.mckay@esa.int Nestor PecciaEsoc/ESANestor.peccia@esa.int Chris TaylorEstec/ESAchris.taylor@esa.int Scott BurleighJPL/NASAscott.burleigh@jpl.nasa.gov
3
What we learnt NASA and ESA both have infrastructure in place but the capability for relaying data between elements is very basic, essentially bitstream (ExoMars assumes packets) Proximity 1 protocol is operating as specified but it took an extremely long time to identify, negotiate and test the previous implementations (no CCSDS prototyping!) X-support points are project negotiated and not brought into the CCSDS standards regime, actual x-support capabilities are not widely publicised The real issue is not with Proximity-1 but with the data that it carries – which services and protocols are used for data exchange – thus a real internetworking and x-support issue that should have already been tackled in CCSDS The result: CCSDS presently has no clear interoperability strategy for current and future Mars missions.
4
What we propose to do Form a Mars working group with 3 outputs: –A PICS (protocol implementation conformance statement) proforma –A magenta book documenting the scenarios, protocol profiles and end- to-end x- support services to be used for Mars missions circa 2010 –A green book which gives an evolutionary path for the protocols, interoperability and x-support for Mars missions beyond 2010
5
PICS – ISO definition A Protocol Implementation Conformance Statement (PICS) Proforma is a companion standard to an OSI protocol standard. It describes all the capabilities and options within a protocol and is completed by the supplier of a product claiming to implement the protocol. The PICS is developed in the form of a questionnaire and the filled out questionnaire becomes the PICS for the product. It indicates which capabilities and options have been implemented and what limitations might prevent interworking. It allows a customer of the product to evaluate its conformance to the standard and to determine whether the product meets the customer's requirements.
6
PICS for Proximity-1 The PICS proforma for proximity-1 is proposed as three annexes, one for each of the CCSDS Proximity-1 Recommendations – pink sheet process Implementers of Prox-1 should document their implementation using the proforma and use it to demonstrate conformance and capabilities A great deal of information already exists from current implementations and this can be used to derive the proforma, work to be shared between NASA and ESA It is recommended that all CCSDS protocols, present and future, are complemented by PICS proforma as this will improve the compliance to our Recommendations and clearly identify incompatibilities
7
Mars Profiling – Issue 1 (descriptive only - not perfect ISO) Prox-1 Protocol stack CCSDS Stack ? protocol Application Prox-1 Protocol stack ? Services Agency A Landed element Agency B Orbiter Agency B Ground Infrastructure Agency A Ground Infrastructure X-Support point CCSDS Stack Application ? Services CCSDS Stack CCSDS Stack ? protocol X-Support point For Agency A to communicate using resources of Agency B both ground and flight x-support points need to be defined. For the current Mars missions these are mostly ad-hoc and not defined by CCSDS
8
Mars Profiling – Issue 2 Orbiter with Legacy Protocols Rover with Legacy protocols Orbiter with Future Protocols Rover with Future protocols Even if we are able to agree on an updated set of x-support services and protocols, we will remain with the issue of legacy hardware which may have a fixed implementation OK ?
9
Mars Profiling – Issue 2 Orbiter with Legacy Protocols Rover with Legacy protocols Orbiter with Future and legacy Protocols Rover with Future and legacy protocols If new elements implement new protocols they must also implement legacy protocols, we therefore probably need two protocol profiles All OK
10
Summary of Magenta book Identify the international elements which will be in place in the course of the next 10 years Document their capabilities and requirements, together with possible adaptations to arrive at a set of scenarios covering the end-to-end transmission system Specify the interoperability points and select the services and protocols to be used for internetworking Provision of protocol profiles to be used. Space Packet Protocol (ESA) and Legacy protocol (JPL). Note that prototyping may be applicable if non CCSDS x-support services are selected
11
Green Book - Need The work previously described should provide a workable Mars solution for the near future without changing the present Agency infrastructures. This is urgently needed and necessarily based on existing protocols However, the capabilities provided are likely to be very basic, and may not support the necessary growth as new elements arrive It may also result in an entrenched set of implementations that are unable to take advantage of emerging needs and related CCSDS developments It is therefore proposed to develop, in parallel, a CCSDS Green book which shows an evolutionary path for internetworking services and protocols to be used beyond circa 2010
12
Green book Contents Proposal The green book will take account of the profiles developed under the Magenta book activity and propose an evolutionary path for improving the capabilities of Mars based missions beyond 2010, typically it would cover: –Provision of a notional Mars network topology based on Mars mission proposals under consideration at ESA, NASA, and other agencies –Definition of capabilities and services predicted to be required and the operational scenarios that need to be supported –An analysis and trade-off of the most appropriate protocols to meet our needs –Identification of x-support and interoperability points –Proposed protocol stack diagrams accommodating the notional Mars network topologies, highlighting the insertion of new protocols –Plan for assuring continuation of support for legacy infrastructure as new capabilities are introduced Discussions on physical and datalink layers would be covered only to the extent of that needed for internetworking
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.