Space Communications Cross Support Architecture Working Group

1. Space Communications Cross Support Architecture Working Group Action Item (Fall, 2008) #2: Relationship between the IOAG Cross Support Service Architecture White Book and the CCSDS Cross Support Reference Model Fred Brosi February, 2009

2. Action Item #2 from CSA-WG: “Analyze the relationship between the IOAG Cross Support Service Architecture White Book and the CCSDS Cross Support Reference Model Green [actually, Blue] Book.” Note: The draft IOAG Cross Support Service Architecture has become the initial draft of the CCSDS Cross Support Service Architecture White Book

3. CSSA:SLE-RM CSSA SLE-RM • Scope: Space communications cross support1 • 4 Views: • Service • Physical • Communications • Enterprise • Scope: Cross-support transfer & management services • 2 Views: • The RM Functional View is roughly equivalent to the CSSA Service View • The RM Cross-support View has aspects of both the Physical and Enterprise Views 1 –from the WG Charter. So should CSSA be SCCSA? Should CSA-WG be SCCSA-WG?

4. SLE-RM Cross-support View • “The cross support view…provides the means to model allocation of the functions identified in the functional view to real systems under independent management authorities, which are named SLE Complexes. The cross support view also describes the management interactions between SLE Complexes and the SLE Utilization Management on behalf of the MDOS.” • RM’s implied physical view is: • Space element and ground element are physically separated • RM’s implied enterprise view is: • The ground element components (SLE System and MDOS) may be physically separated, but are assumed to belong to different organizations • The SLE System that supports a mission comprises one or more SLE Complexes, which may be physically separated, but are assumed to belong to different organizations (or, at least, the MDOS must arrange services with each separately) • These concepts could be modeled easily using CSSA.

5. SLE-RM Functional View • “The functional view…defines the functions (and their management) that may be performed by an SLE system, without regard to the way these functions are allocated to various management authorities in real systems. The functional view decomposes the SLE system into elementary functions, called SLE Functional Groups (SLE-FGs), that transfer and deliver return and forward data between the space element and the [mission users].” • “Each SLE-FG performs a related set of functions that provide one or more related SLE transfer services.” • The SLE-RM Functional View could be expressed as a Service View under CSSA.

6. CSSA, SLE-RM, and other Space Architectures and Reference Models • CSSA–Space Communications Cross Support Architecture • SLE-RM SLE–Cross Support Reference Model • RASDS–Reference Architecture for Space Data Systems • NASA SCaN ADD–Integrated Network Architecture Definition Document • SISG Report–Recommendations on a Strategy for Space Internetworking

7. Views 1 The SLE RM defines a “Cross-support View” that is essentially an Enterprise View, but includes some aspects of a Physical View.

8. Scope • RASDS–is intended to describe data systemarchitectures and designs within the space domain • CSSA–to be used as a common framework when IOAG Agencies provide and use space communications cross supportservices and develop systems that provide cross support services • NASA SCaN ADD–describes the services and capabilities to be provided by the SCaN integrated network architecture for the time period 2009-2025, and theprogression of the current architecturetoward achievement of the target architecture. • IOAG SISG–spaceinternetworking and international interoperabilityat the Network layer of space communications. The functionality of the Network layer of the ISO OSI communications stack, including its dependencies and effects on lower and higher layers. • SLE-RM–provides a common basis for coordinating the development of CCSDS Recommended Standards for Space Link Extension (SLE) service specifications

9. Scope: RASDS, CSSA, and SLE-RM RASDS CSSA Interoperable Spacecraft Onboard Interfaces Space Data Systems Space communications Systems SLE-RM Station-to-Mission Cross-support: SLE-Transfer (CSTS) & Cross-support Management Services Highly Efficient Communications in Resource-Constrained Environments Standard Data Interchange and Archiving Services

10. Scope: RASDS, CSSA, and SLE-RM RASDS: Space Data Systems Application Layer SLE-RM: Station-to-Mission Cross-support Network Layer Link Layer CSSA: Space Communications Systems

11. Scope: RASDS, CSSA, SLE-RM, IOAG SISG, and NASA SCaN ADD IOAG Agencies Non-IOAG Agencies … … ASI CNES NASA BNSC RASDS: Space Data Systems Application Layer SLE-RM: Station to Mission Cross-support IOAG SISG: Space Internetworking – Layer 3 Network Layer Link Layer SCaN ADD Space Communications Systems CSSA

12. Enterprise View • RASDSEnterprise View • Purpose, scope, and policies for the space data system. Organizational entities and relationships; their roles, requirements, goals, objectives, scenarios, constraints; and how to meet them. • CSSA Enterprise View • Processes and rules governing the initiation, negotiation, and agreement between the supported and supporting Agencies for the provision of cross support services. Administrative and contractual aspects of the service architecture. (Policies, Documents, Pricing, Service agreement, interface testing • SCaN ADD Enterprise View: • Processes and rules governing the initiation, negotiation, and agreements between supported missions and provider networks for the provision of standard services and support; specifically addresses the administrative and contractual aspects of the service architecture • SISG Report Enterprise View • Organizational structure associated with space communications systems and scenarios and its administrative characteristics; physical and administrative interfaces between organizations; documents exchanged between organizations. • SLE-RM Enterprise (Cross-Support) View • An SLE Complex is a set of SLE Functional Groups under a single management authority. At the time of cross support, an SLE complex has a single established relationship between the SLE system and the MDOS .

13. Functional/Service View • RASDSFunctionalView • Functional decomposition of the space data system into abstract objects that interact at interfaces. It describes the functionality provided by the space data system, the behavior of the functional elements, and their functional decomposition. • CSSA Service View • Services provided by cross support service systems/elements, their functional and performance characteristics, and methods and/or standards for using and managing services. • SCaN ADD Service View: • The proposed repertoire of standard service offerings that SCaN networks provide to flight missions, including a functional description of each service type, and the service management function processes that flight missions use to obtain, specify, access, and use SCaN services. • SISG Report Service View • Services (which are functions provided by some physical elements for other physical elements), their functional and performance characteristics, and methods and/or standards for using and managing services. • SLE-RM FunctionalView • Functions that provide SLE transfer services, implemented by SLE-Functional Groups (FGs). Each SLE-FG performs a related set of functions that provide one or more related SLE transfer services.

14. Physical/Connectivity View • RASDSConnectivityView • the decomposition of the space data system into components (nodes) that interact across connectors (links). Describes the physical aspects of the space data system and the external environment within which it operates, the physical behavior (and motion) of the nodes, and their physical decomposition. • CSSA Physical View • The Physical View is used to describe the physical configuration of cross support service systems/elements and their physical characteristics: physical location; topology and connectivity; and physical media for access. • SCaN ADD Physical View: • physical description of the SCaN integrated network architecture assets as they change over incremental timeframes ending in 2015, 2020, and 2025; includes physical location, topology and connectivity, and functional and performance attributes. • SISG Report Physical View • The Physical View is used to describe the physical configuration of cross support service systems/elements and their physical characteristics: physical location; topology and connectivity; and physical media for access. • SLE-RM Physical (Cross-Support) View • Physical systems that interoperate to provide SLE services to a space mission may be independently operated by different Agencies or by different organizational elements within an Agency. In the cross support view, each such physical system is modeled as an SLE Complex .

15. Communications View • RASDSCommunicationsView • The mechanisms and functions required to engineer and implement the protocols and communications standards for the space data system, including implementation choices and specifications, and allocation of communications functionality to engineered components of the system. • CSSA CommunicationsView • The communications protocols used for accessing services provided by cross support service systems/elements and the parameter values of communications protocols . • SCaN ADD CommunicationsView: • Protocols and standards employed to provide the end-to-end communications in support of SCaN services, including the protocol parameter values or types. • SISG Report CommunicationsView • The communications protocols and modulation/coding methods used between physical elements and their communicational characteristics, and the parameter values of communications protocols. • SLE-RM Communications View • N/A.

16. Other Views • Information View • RASDS: information handled by the system, the semantics of the information, and the interpretation of that information. It describes the information managed by the space data system along with the structure, content, semantics, type, relationships, and constraints on the data used within the system. • Operations View • SCaN ADD: scenarios describing the operational activities that will be conducted by the networks, and in some cases, the supported flight missions.