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Suggested Citation:"5 Data Standards Management." National Research Council. 2007. Review of the Space Communications Program of NASA's Space Operations Mission Directorate. Washington, DC: The National Academies Press. doi: 10.17226/11718.
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Suggested Citation:"5 Data Standards Management." National Research Council. 2007. Review of the Space Communications Program of NASA's Space Operations Mission Directorate. Washington, DC: The National Academies Press. doi: 10.17226/11718.
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Suggested Citation:"5 Data Standards Management." National Research Council. 2007. Review of the Space Communications Program of NASA's Space Operations Mission Directorate. Washington, DC: The National Academies Press. doi: 10.17226/11718.
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Page 40
Suggested Citation:"5 Data Standards Management." National Research Council. 2007. Review of the Space Communications Program of NASA's Space Operations Mission Directorate. Washington, DC: The National Academies Press. doi: 10.17226/11718.
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Page 41
Suggested Citation:"5 Data Standards Management." National Research Council. 2007. Review of the Space Communications Program of NASA's Space Operations Mission Directorate. Washington, DC: The National Academies Press. doi: 10.17226/11718.
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Page 42
Suggested Citation:"5 Data Standards Management." National Research Council. 2007. Review of the Space Communications Program of NASA's Space Operations Mission Directorate. Washington, DC: The National Academies Press. doi: 10.17226/11718.
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Page 43
Suggested Citation:"5 Data Standards Management." National Research Council. 2007. Review of the Space Communications Program of NASA's Space Operations Mission Directorate. Washington, DC: The National Academies Press. doi: 10.17226/11718.
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Page 44

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5 Data Standards Management INTRODUCTION nent level, of reinventing for each application. Yet these components can be combined in ways that make them unique There is agreement among the world’s space agencies and appropriate for a variety of purposes. To be effective, that the use of standardized techniques for handling space standards must be developed by users, rather than imposed data is beneficial to all. Although data formats are generally from outside. Users must be motivated to look for common- standardized, the standards activity for space data is more alities, not differences. complex, involving designing or adopting systems and pro- What are some of the motivations to standardize? Gen- cedures that can utilize these standardized data formats. In erally, as technology develops and markets grow, pressures this context, the term “data standards” encompasses stan- for standardization increase, primarily for economic reasons. dards for the end-to-end transmission, handling, and storage Standards permit mass production, thereby reducing both of all data associated with space operations: scientific data production and ownership costs, and they facilitate expan- originating on spacecraft, uplink and downlink data needed sion of markets, permitting products developed for one mar- to conduct associated operations, tracking data, and even ket to be sold elsewhere. There are also motivations beyond voice communications with astronauts. As with other uses of economic incentives for standardizing, such as safety. standards, the objective is to reduce costs and enable Countervailing factors that can inhibit standardization might interoperability by adopting compatible systems and proce- also reflect economic interests, expressed, for example, in dures. internecine battles to gain competitive advantages, or to The role of standards in space operations mirrors the maintain or expand contract bases. Often, simple inertia is history of standards in general, although accelerated by the also an impediment to standardization. extremely rapid development of the associated communica- An international body, the Consultative Committee for tions and computing technologies. Technology typically de- Space Data Systems, commonly referred to as the CCSDS, velops in many places simultaneously, with people doing is the primary organization that develops space-associated similar things differently simply because there is little coor- standards that facilitate and enable more cost-effective mis- dination. Space operations present a classic example of inde- sions through the shared use of common components, proce- pendently developed approaches to data handling. Experts dures, and infrastructure (Box 5.1). SOMD’s data standards were needed to build and operate each of various different program element is essentially synonymous with NASA’s data-handling systems performing essentially the same fun- participation in the CCSDS. damental tasks. Most of the effort is spent on inventing (de- NASA is a founding member of the CCSDS, which is signing and developing), whereas the costs of producing and supported by more than 30 space agencies (and their associ- owning (maintaining) the products are relatively minor. ated industrial bases) distributed across the world space com- Standardization minimizes reinventing. munity. Acting as a technical arm of the International Orga- Assuming agreement in principle that standardization is nization for Standardization (ISO), CCSDS generates the desirable, how can it be done right? The first step is to under- world body of standards in the field of space data and infor- stand what it makes sense to standardize. Standardization mation transfer systems. The CCSDS is the undisputed world generally focuses on interfaces: compatible form, fit, and leader in space data standardization, and to date well over function where components join. Standard components avoid 300 space missions are able to interoperate using these stan- the expense of reengineering and redesigning at the compo- dard capabilities. Within the United States, virtually all 38

39 DATA STANDARDS MANAGEMENT NASA space missions—and a growing number operated by in this case, providing significant leadership to—the CCSDS.4 All CCSDS member organizations are fully in- NOAA, the DOD, and U.S. industry—implement a signifi- cant complement of CCSDS standards. Specific missions are volved in the planning and review process. listed in Table 5.1. The standards management program element’s CCSDS products are properly termed and treated as rec- deliverables are also articulated in the CCSDS’s strategic plan.5 The expected services continue to be delivered by this ommendations that space mission programs are free to ac- cept or reject as they determine best for their individual pro- program element’s activities. The planning is well supported grams. In this regard, neither the data standards management and documented in the strategic plan, and appropriate cus- program element nor the broader SOMD program exercises tomer agreements are in place. The deliverables, which are any control over adoption of the standards. Establishment coordinated and agreed to by the customers as indicated by and approval of any “waivers” are totally outside the pur- their participation in the collaborative development, provide view of SOMD. Thus, the degree to which spaceflight mis- sufficient near-term standards and metrics according to sions adopt recommended standards is a meaningful metric which the standards management program element can be of the usefulness of SOMD’s data standards management regularly assessed. There appears to be little value in devel- element, and the committee has accordingly attempted to oping off-ramps to enable reallocation of funding, given the determine the degree of adoption. Table 5.1 lists 78 new continuing delivery of the agreed-to standards. The interna- space missions that have adopted CCSDS standards recom- tional scope of the activity would make an independent re- mendations in whole or in part.1 In addition, other organiza- view of the CCSDS program complex, likely not adding sig- tions frequently see compatibility with NASA space com- nificant value, given that the members continually review munications standards as a valuable means of enabling their individual participation in the activity. There is no evi- support or cross-support with NASA assets. dence that NASA has previously had independent or exter- Although the evidence to date is not compelling that nal reviews of its participation in the CCSDS. NASA’s mission directorates have a clear understanding of The program element’s objectives, developing standards the benefits of adopting standards, there are indications that in coordination with and subscribed to by space activities the directorates are coming to recognize the value to their around the world, are appropriate. Adequate personnel and programs of adopting standards. One such observation fo- resources are available, as evidenced by the continuing de- cused on utilization by JPL and GSFC as discussed in Box velopment and adoption of common standards. 5.2. Connections to the Broader Community ASSESSMENT The data standards management program element fo- cuses on national and international collaboration aimed at Formulation of the Program Plan achieving consensus on space data standards, and thus it nec- The standards management program element’s goals essarily has forged extensive and effective connections with and objectives are clearly defined. As explicitly stated in the the broader community, which contributes to the develop- charter of the CCSDS: “The major space agencies of the ment of standards and shares ownership in the process and world recognize that there are benefits in using standard tech- products. niques for handling space data and that, by cooperatively CCSDS standards find their way into the space-related developing these techniques, future data system interoper- communications and Internet Protocol marketplace. In cal- ability will be enhanced.”2 The Strategic Plan of the Con- endar year 2005, the CCSDS surveyed the dollar value of the sultative Committee for Space Data Systems identifies and U.S. space communications protocol marketplace and con- cluded that the value exceeded $24 billion per annum.6 If defines the goals and objectives of the international forum in which this NASA program element plays a leadership role. accurate, this would represent a very impressive return on As stated in the plan’s vision: “The NASA Communications investment, given the very modest NASA investments (see & Data Standards Program provides the forum to advocate, “Resources and Funding”). coordinate, and recommend NASA, interagency, and inter- Participation by the Department of Defense, the U.S. national data communications standards required to carry out commercial space industry, and others in developing space NASA missions, including NASA participation in interna- data standards is evidence that NASA’s data standards work tional missions.”3 is appropriately recognized and is effective. This program By its basic nature, the scope of this program element element leverages other work done in the U.S. government extends beyond NASA. As noted above, standards develop- and industry, as well as by international associates. ment must be a broad-based effort, both to ensure full recog- NASA appears to use out-of-house resources effectively nition of the needs of the broader user community and to to supplement its civil service team in providing leadership obtain buy-in by those users. In this regard, NASA accom- for the development of standards, with the latter managing plishes associated objectives through participating in—and and coordinating the program element and the former per-

40 REVIEW OF THE SPACE COMMUNICATIONS PROGRAM BOX 5.1 it also must address new areas for standardization and incorporate new Consultative Committee for Space Data Systems technologies. The challenges of capitalizing early on advancing technol- ogy while dealing with increasing budgetary pressures continue to con- The Consultative Committee for Space Data Systems (CCSDS) was front the agency. formed in 1982 by the major space agencies of the world to provide a Within the CCSDS structure, a member agency is a governmental or forum for discussion of common problems in the development and op- quasi-governmental organization that fully participates in all CCSDS eration of space data systems.1 It is currently composed of 10 member activities and provides a commensurate level of support. Unlike other agencies, 22 observer agencies, and more than 100 industrial associ- participating entities, each member agency has CCSDS voting rights ates. Since its establishment, it has been actively developing recom- and thus the power to decide on CCSDS business. Member agencies mendations for data- and information-systems standards to reduce the name to the CCSDS Management Council individual representatives who cost to the various agencies of performing common data functions by exercise member agency voting rights to determine the overall direction eliminating project-unique design and development, and to promote of the organization. The CCSDS has over 100 active associate members. interoperability and cross-support2 among cooperating space agencies These associates are typically U.S. aerospace corporations that are con- to reduce operations costs by sharing facilities and other common re- sumers of CCSDS publications and products. sources. Objectives and goals are defined for six areas: systems engineering, In 1991, the CCSDS entered into a cooperative arrangement with the mission operations and information management, cross-support ser- International Organization for Standardization (ISO). Under this arrange- vices, spacecraft onboard interface services, space link services, and ment, CCSDS recommendations are advanced to Subcommittee 13 space internetworking services. Within each of these areas, specialized within Technical Committee 20 (Aircraft and Space Vehicles), where working groups are chartered to develop recommended standards. Rec- they then advance via the normal ISO procedures of review and voting to ommended practices and experimental standards have also been added become full international standards. A telling indicator of the broad un- as additional categories to the specification hierarchy. derstanding and appreciation of this effort is the degree of participation in developing the standards, and the degree to which they are subse- quently adopted and used in space programs. 1Consultative Committee for Space Data Systems (CCSDS), About CCSDS, Although the growing acceptance of its recommendations is testi- available at http://www.CCSDS.org. mony to the quality of the CCSDS’s work, much remains to be done. Not 2Cross-support is the cross-utilization of operational resources among agencies. only must NASA continue to maintain the current recommendations, but forming the detailed work. This balance seems quite appro- mulation of draft positions. Often the give-and-take of the priate to the endeavor, as evidenced by the demonstrated and technical people as well as voting by the Engineering Steer- continuing success in delivering coordinated standards. ing Group and the Management Council occurs in this e- The benefits and costs of increasing interoperability forum. with military space systems, commercial space systems, and The committee judged the standards management pro- the systems of foreign space agencies seem properly consid- gram element planning to be quite well crafted, as evidenced ered, as evidenced by the direct involvement in ongoing stan- by the program element’s long history of demonstrated suc- dards development activities. The basic motivation for de- cesses. Since its formation in 1982 the CCSDS has grown to veloping space data standards is to increase reliability and 10 member agencies and 22 observer agencies. As noted, the efficiencies with military, commercial, and foreign space CCSDS has a currently active suite of 78 standards, 29 of operators, with the attendant benefits and cost savings which have become ISO standards. Table 5.1 lists more than achievable by enabling interoperability. 70 new missions slated for launch in 2006 through 2008 that have adopted CCSDS standards in whole or in part. Such accomplishments would not have been possible without ef- Methodology fective planning and execution, particularly when the lim- The primary component of standards development is ited authority of the CCSDS is taken into consideration. working groups that meet on a periodic and rotating basis.7 Virtual collaboration is used effectively to minimize the need Resources and Funding for the physical presence of working group members. The Collaborative Work Environment, a secure area in the NASA’s funding and level of effort for the total CCSDS program are as follows:8 SOMD (Space Operations), $5 CCSDS website, enables all working groups and area direc- tors to have “net meetings” or to submit products, papers, or million annually and SMD, $1.5 million annually. Neither draft positions asynchronously for commentary and the for- ESMD (Exploration) nor PAE (Chief Engineer) contribute

41 DATA STANDARDS MANAGEMENT TABLE 5.1 Missions That Implement Consultative Committee for Space Data Systems Standards Launch Related Mission Description Date Organizations NPP National Polar Orbiting Operational Environmental Satellite System 2006 (Dec.) NASA/GSFC (NPOESS) Preparatory Project AIM Aeronomy of Ice in the Mesosphere 2006 (Sept.) NASA/GSFC SBIRS-High Space Base Infrared System 2006 DOD New Horizon Pluto-Kuiper belt mission 2006 NASA/APL Dawn Meteorite Explorer 2006 JPL, UCLA THEMIS 5 Time History of Events and Macroscale Interactions during Substorms 2006 NASA/SSL THEMIS 4 Time History of Events and Macroscale Interactions during Substorms 2006 NASA/SSL THEMIS 3 Time History of Events and Macroscale Interactions during Substorms 2006 NASA/SSL THEMIS 2 Time History of Events and Macroscale Interactions during Substorms 2006 NASA/SSL THEMIS 1 Time History of Events and Macroscale Interactions during Substorms 2006 NASA/SSL Solar-B 2006 ISAS GLAST Gamma-ray Large Area Space Telescope 2006 NASA COROT Convection Rotation a Transits planetaires (Convection Rotation and Planetary Transits) 2006 CNES INMARSAT 4F 3 International Maritime Satellite 4F3 2006 INMARSAT GOCE Gravity Field and Steady State Ocean Circulation Explorer 2006 ESA ATV-3 Automated Transfer Vehicle 3 2006 ESA CRM Coral Reef Mission 2006 PCRF, MIT/CSR RascomStar-Qaf 1 Telecommunications 2006 (June) RascomStar-QAF ARABSAT4B 2006 ARABSAT ARABSAT4A 2006 ARABSAT SKYNET 5B 2006 British Ministry of Defence SKYNET 5A 2006 British Ministry of Defence HOTBIRD 8 Telecommunications 2006 Eutelsat Anik F3 Telecommunications 2006 Telesat Canada/ESA Galaxy 17 Telecommunications 2006 PanAmSat/ESA COSMO-Skymed3 Mediterranean Basin Observation 2006 ASI COSMO-Skymed2 Mediterranean Basin Observation 2006 ASI Rømer After the Danish astronomer Ole Rømer 2006 DSRI Formosat3/ Republic of China Satellite-3/ 2006 (Mar.) NSPO ROCSAT-3/ Constellation Observing System COSMIC 6 Formosat3/ Republic of China 2006 (Mar.) NSPO ROCSAT-3/ COSMIC 5 Formosat3/ Republic of China 2006 (Mar.) NSPO ROCSAT-3/ COSMIC 4 Formosat3/ Republic of China 2006 (Mar.) NSPO ROCSAT-3/ COSMIC 3 Formosat3/ Republic of China 2006 (Mar.) NSPO ROCSAT-3/ COSMIC 2 Formosat3/ Republic of China 2006 (Mar.) NSPO ROCSAT-3/ COSMIC 1 ST5 3 Space Technology 5 2006 (Mar.) NASA ST5 2 Space Technology 5 2006 (Mar.) NASA Cassiope ePOP probe meteorological satellite 2007 CSA SBSS Space-Based Space Surveillance 2007 NASA/GSFC ADM-Aelous Atmospheric Dynamic Mission 2007 (Oct.) ESA OCO Orbiting Carbon Observatory 2007 (Oct.) NASA/GSFC GOSAT Global Climate Observation System 2007 JAXA COF Columbus Orbital Facility 2007 DLR Aeolus-S Sim 2007 ESA Aeolus-X 2007 ESA continued

42 REVIEW OF THE SPACE COMMUNICATIONS PROGRAM TABLE 5.1 Continued Launch Related Mission Description Date Organizations Orbview 5 Commercial Imaging Satellite 2007 GSFC Star-One C-2 2007 ESA Planck Satellite for the imaging of the anisotropies of the cosmic 2007 ESA background radiation Herschel Space Formerly Far Infrared and Submillimetre Telescope (FIRST)—ESA 2007 ESA Observatory Horizon 2000 cornerstone 4 (CS4) SDO Solar Dynamic Observatory 2007 NASA/GSFC Kepler Satellite for the search of Earth-size and smaller planets 2007 NASA Ames SMOS Soil Moisture and Ocean Salinity 2007 ESA/CNES/SNP Megha-Tropiques Convective systems, water cycle, and energy budget in the 2007 CNES/ISRO tropical atmosphere Solar Probe 2007 NASA/JPL Mars Premier Orbiter 2007 CNES ACCESS Advance Cosmic Ray Composition Experiment for the Space Station 2007 NASA/GSFC ATV-4 Automated Transfer Vehicle 4 2007 ESA HTV-01 H-II Transfer Vehicle 2007 JAXA HTV-DM H-II Transfer Vehicle Demonstration Flight Model 2007 JAXA Phoenix Study Mars Polar Region 2007 NASA COSMO-SkyMed4 Constellation of Small Satellites for Mediterranean Basin Observation 2007 ASI THEOS Thai Earth Observation System 2007 GISTDA Orbview-5 Commercial remote sensing satellite 2007 ORBIMAGE Astra-1M Telecommunication Satellite 2008 ESA LRO Lunar Reconnaissance Orbiter 2008 NASA GSFC ZX 9 (Chinasat) Telecommunications Satellite 2008 Spirale 2 Early Detection System 2008 CNES Spirale 1 Early Detection System 2008 CNES Eddington L2 Astroseismology Mission 2008 (June) ESA Chandrayaan-1 Lunar Mission 2008 ISRO Skynet 5C 2008 British Ministry of Defence GLORY The GLORY satellite is an Earth science mission that uses the 2008 NASA/GSFC refurbished bus of the cancelled VCL satellite MSG-3 Meteosat Second Generetion-3 2008 ESA ATV-5 Automated Transfer Vehicle 5 2008 ESA SST Space Solar Telescope 2008 CNSA HTV-03 H-II Transfer Vehicle 2008 JAXA HTV-02 H-II Transfer Vehicle 2008 JAXA Picard 2008 CNES Pleiades HR 1 Pleiades High Resolution 1 2008 CNES, ASI SOURCE: John D. Kelley, NASA, “NASA Communications and Data Standards Program,” briefing to the NRC Committee to Review NASA’s Space Communications Program, Washington, D.C., January 26-27, 2006, pp. 13-14, 16-18. any funding. (Recall the point above that the total value of sumers and the private-sector producers and vendors of pri- CCSDS standards was said to exceed $24 billion per an- vate-sector communication applications with CCSDS stan- num.) dards integrated into them. The corresponding figures for CCSDS activity outside CCSDS member agencies of other countries contribute NASA are not readily available. A way of estimating the to CCSDS in the form of full-time-equivalent (FTE) person- level of effort is to consider that the CCSDS has 130 active nel. Typically the European Space Agency (ESA) matches associate members, typically U.S. aerospace corporations NASA’s contribution, and the Japanese Aerospace Explora- that are consumers of CCSDS publications and products. tion Agency plus a number of other agencies such as INPE These companies adopt or adapt the CCSDS line of products (Brazil) contribute roughly one-fourth of the total contrib- to their own applications. The USAF and other agencies are uted by NASA plus ESA. also consumers of CCSDS products, which usually come to The CCSDS Operating Plan for Standards Develop- ment,9 which is subordinate to the CCSDS strategic plan, is them via the associate members. There is an indirect eco- nomic relationship between corporate/U.S. government con- updated yearly and defines near-term products in detail. Sys-

43 DATA STANDARDS MANAGEMENT BOX 5.2 tions. Other missions, like Messenger, used CFDP on-board in a fully Examples of CCSDS Usage by NASA Centers automated approach, with no human in the loop. Most of the Mars rover missions have adopted a file management and retransmission method that was first used on Mars Pathfinder. This has Jet Propulsion Laboratory been driven by a desire to be able to more closely manage downlink As described by NASA, JPL tends to strictly enforce compliance prioritization, on-board data handling, and uplink bandwidth. It also pro- with use of CCSDS standards mainly because much of the CCSDS’s vides support for handling compressed data in a way that recognizes the work addresses the challenges of deep-space links such as poor quality need to handle compression block boundaries to support error contain- of service and other problems associated with sending radio frequency ment. Discussions are in progress to identify ways to accommodate all of (RF) waves across the solar system. All JPL missions since Mars Ob- these needs within the CFDP specification, or in some simple extensions server have complied at the link layer and below, meaning that they are to the specification that NASA will propose to CCSDS. using standard TC and TM at the link layer, or Advanced Orbiting Sys- Many of the higher-level CCSDS protocols either are not appropriate tems (AOS) for high-data-rate missions, for direct to Earth (DTE) or for use in deep space or are not yet mature enough to be adopted. These direct from Earth (DFE) links. The Command Operation Procedure (COP- include Space Link Extension (SLE) Service Management, and Spacecraft 1) with the Frame Acceptance and Reporting Method (FARM) is typi- On-board Interface Services (SOIS). The command/uplink SLE data trans- cally used for uplink reliability. Because two-way recall times are very fer protocols (SLE-FCLTU) are effectively in use by all missions that use long in deep-space applications, downlink data are typically sent in “un- the Deep Space Network (DSN) since they are part of the command sub- reliable” modes, although various nonstandard retransmission schemes system. The SLE downlink protocols (SLE-RAF, SLE-RCF) are being used are in use for critical frame or packet data. widely by the DSN to provide cross-support to external missions. CCSDS The rover and lander missions are configured similarly for their standards for exchange of navigation data (orbits) are just coming into DTE/DFE links, but they also use Proximity-1 in reliable mode for their use. Other navigation data exchange standards (tracking, attitude) are ex- orbiter-to-landed element links. The bulk of data being transferred from pected to be adopted as they become finalized. the very successful MER Rovers has come down over Proximity-1 re- Future JPL missions are expected to adopt the existing space link lays to Odyssey and other orbiters. Odyssey and the other orbiters that protocols and to also adopt more fully the use of CFDP. As support is support relaying also implement Proximity-1 for these local links. provided for more networked sets of missions NASA expects to see use of Some of the hardware implementations of Proximity-1 have known the standard relay operations in CFDP, and eventually to see use of the problems (CE-505 radio), but there are well-understood work-arounds newly developed Delay Tolerant Networking (DTN) protocols. These pro- for these. The missions using this radio tend to be compliant with the tocols, and the SCPS, Internet tuned for space, protocols are more likely Proximity-1 standard at the undifferentiated byte stream (rather than to see first use in the lunar environment in support of Constellation. packet stream) level. The more recent radio implementation— Electra—does not have this problem; it is a software defined radio that Goddard Space Flight Center can be reconfigured as needed to support a fully compliant Proximity- Nearly every Goddard mission in the past 10 years has used the 1 link protocol. NASA expects that future missions using Electra will CCSDS telecommand protocols (including COP-1) for commanding and be fully compliant at the packet transfer level to better support relay the TM/AOS protocols for telemetry. (TM was used for telemetry until AOS operations. replaced it.) The rare exceptions to the general rule are typically very small Below the link layer, other CCSDS and Space Frequency Coordi- missions, for example, a balloon experiment out of Wallops. nation Group (SFCG) standards are used for coding, modulation, and Goddard missions that use CCSDS telecommand and telemetry pro- appropriate selection of frequencies. A variety of different frequencies tocols include FAST, SWAS, WIRE, SAMPEX, HESSI, TRACE, SWIFT, and coding approaches are used, depending on the operating environ- GLAST, XTE, TRMM, MAP, IMAGE, EO-1, ST5, SDO, and LRO. (Some of ment and characteristics of the mission links. Reed-Solomon, Convolu- these missions are still in development.) tional, and now Turbo codes are used. High-data-rate missions are ex- The GPM mission started on a non-CCSDS track but returned to pected to use Deep Space LDPC codes as these are stabilized in the CCSDS when the designers discovered that spacecraft vendors had con- future. siderable knowledge, experience, and a reliable track record with CCSDS Above the link layer a variety of different approaches are used for file protocols—qualities not evident with the alternative that was being con- delivery. Some missions have fully embraced the CCSDS File Delivery sidered. Protocol (CFDP) and used it successfully for uplink and downlink file Although CFDP is not universally used, it is gaining acceptance, with transfers. Where missions are flying on-board file systems this is easier planned use by JWST, LRO, GPM, and (possibly) MMS. Reasons given to accomplish, but even some missions that do not fly file systems have for not using CFDP include “it didn’t exist when we designed our mission” found it useful to adopt CFDP protocol elements and use the standard and “it doesn’t have Goddard flight heritage.” CFDP ground implementation. This provides lower-risk and lower-cost ground system implementation. One mission, Deep Impact, used JPL- SOURCE: John D. Kelley, NASA SOMD, March 1, 2006. developed CFDP software for both its flight and ground implementa-

44 REVIEW OF THE SPACE COMMUNICATIONS PROGRAM As NASA has noted,12 the majority of the resources tem-level assessments are conducted routinely as an integral aspect of developing the operating plan. The CCSDS strate- applied to standards development are people with unique gic plan is updated as necessitated by changing events, and expertise, and thus overlap in personnel resources is usually at least every 3 years. The strategic plan redefines goals, the minimal. Assimilation of the common threads that contrib- organization’s current objectives, and domains for standard- ute to standards development usually occurs via agency-wide ization as appropriate. Development of the operating and and international working groups; therefore standards devel- strategic plans evidences planning that is thoroughly consid- opment work tends not to be tied to geographic locations, ered, projecting future activities that are both reasonable and such as specific NASA centers. justifiable. Managers executing plans for the data standards pro- Finding: It appears that the expected services are being suc- gram have both an understanding of the objectives and pro- cessfully provided by NASA’s space data standards manage- cesses for space data handling, and an acceptable ability for ment program element, as evidenced by the continuing de- risk10 management, as demonstrated by their continuing suc- velopment of standards that are being adopted by space cess in delivering standards in a timely manner and within activities around the world. The relatively modest funding available resources. allocated seems stable, and no funding threats are foreseen. NOTES Overall Capabilities 1. Kelley, John D., “NASA Communications and Data Stan- The quality of the work of NASA’s data standards man- dards,” briefing to the NRC Committee to Review NASA’s Space agement program element is clearly comparable with that of Communications Program, Washington, D.C., January 26-27, 2006. other world-class efforts, as demonstrated by the fact that 2. Consultative Committee for Space Data Systems the products—data standards—have been adopted as ISO (CCSDS), About CCSDS, available at http://www.CCSDS.org. standards as appropriate. As noted above, there are currently 3. CCSDS Secretariat, Strategic Plan of the Consultative 78 active publications (standards), of which 29 have become Committee for Space Data Systems, CCSDS A01.1-Y-2, Draft 4, ISO standards. Also, as witnessed by their adoption and use, Version 3, March 8, 2005. the standards meet the requirements of both internal and ex- 4. CCSDS, available at http://www.ccsds.org. ternal customers. 5. CCSDS Secretariat, Strategic Plan of the Consultative The qualifications of the NASA/contractor staff are Committee for Space Data Systems, CCSDS A01.1-Y-2, Draft 4, clearly sufficient to achieve the goals of the data standards Version 3, March 8, 2005. 6. Kelley, John D., NASA SOMD, personal communication, management program element, as demonstrated by its con- March 1, 2006. tinuing success in playing a leading role in CCSDS activi- 7. Kelley, John D., NASA SOMD, personal communication, ties. In addition, the capabilities, quantity, and state of readi- April 24, 2006. ness of the equipment and facilities used to achieve program 8. Kelley, John D., NASA SOMD, personal communication, element goals appear to be quite satisfactory, again given the March 1, 2006. continuing delivery and acceptance of the program element’s 9. CCSDS, CCSDS Operating Plan for Standards Develop- data standards. ment, CCSDS Record A01.2-Y-4 Yellow Book, July 2005. Personnel, equipment, and facilities appear to be used 10. Both the technical risks associated with capitalizing on efficiently, with support contractors effectively complement- technologies that are leading edge, yet sufficiently mature to be ing government personnel. There are no laboratories or other viable, and the risks from working within limited resources. facilities dedicated specifically to standards development. 11. Kelley, John D., NASA SOMD, personal communication, April 26, 2006. Although testbeds are utilized to advance standards devel- 12. Kelley, John D., NASA SOMD, personal communication, opment, existing mission testbeds are normally used as ap- April 24, 2006. propriate to develop prototype standards.11

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The Space Communications Office (SCO) at NASA has two primary roles. The first is to manage two of the communications networks that enable spaceflight operations and research, and the second is to integrate agency-wide telecommunications issues. In 2005, NASA asked the NRC to review the effectiveness of the SCO in carrying out its responsibilities by assessing the overall quality of the space communications program. This report presents a review of each of the program elements within the SCO—the space network, NASA’s integrated space network (NISN), spectrum management, standards management, search and rescue, communications and navigation architecture, technology, and operations integration. The review focuses on formulation of plans for each element, plan development methodology, connections with the broader community, and overall capabilities. Recommendations for improving SCO operations and organization are provided.

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