Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
A Proposal for a Cross Support Service Architecture Takahiro Yamada (JAXA/ISAS) Narita Kaneaki [JAXA] January, 2007 (Issue b) Editorial comment Peter Shames, 3 April 2007 1 BASIC CONCEPTS 2 Purposes of the Cross Support Service Architecture A common architectural framework for cross support services is needed, with which Requirements for cross support can be stated in a common way; Core services and interfaces (which are common to many agencies) can be specified. Agency-specific extensions can be accommodated. Priority of the architecture core elements can be assessed. Inter-agency collaborative development can be on a solid basis. With this framework, coordination and negotiation for interagency cross support can be more efficient. It will facilitate better planning and interface development for collaborative missions between agencies. 3 An example: ESA-JAXA/ISAS BepiColombo Mission MPO MPO+MMO data MMO MPO+MMO data ESA/Cebreros JAXA/Usuda BepiColombo MOC SLE Gateway MMO Ops System MMO Ops System ESA ESOC JAXA/ISAS SSOC ESA provides JAXA/ISAS with space and ground services. JAXA/ISAS provides ESA with ground services. 4 Cross Support Service Architecture (1/2) The cross support service architecture (CSSA) is a standard architecture for cross support service systems. It is the framework that defines standard services, interfaces, and their relationships, providing guidance to: Service providers Ground assets (e.g. GN, ESTRACK, DSN) Space assets (e.g. DRS, Lunar relay, Mars relay) Service users: flight missions Space assets (e.g. Spacecraft, landed vehicles) Ground assets (e.g. Mission Operations Center) 5 Cross Support Service Architecture (2/2) The cross support service architecture employs the conventional “service-provider/service-user” model to include both space and ground users. Space Service Users Space Services Cross Support Service System (Service provider) Ground Services Ground Service Users The scope of the architecture is limited to four views: Service View Physical View Communications View Enterprise View 6 Definitions: Cross Support Service Systems/Elements A cross support service system (CSSS) is defined as a set of cross support service elements that are managed by a single authority with a single set of management policies. A cross support service element (CSSE) is defined as a physical element that can provide one or more cross support services to any space mission element of any space agency provided that the customer element conforms to the technical interface specifications and management policies specified for the CSSE. A cross support service element can be an element on the surface of a heavenly body (e.g., Earth, the Moon, and Mars), an element orbiting around a heavenly body, or an element in cruise through space. 7 Examples of Cross Support Service Systems The following are some examples of Cross Support Service Systems and Cross Support Service Elements. Cross Support Service System (Examples) Cross Support Service Elements (Examples) Deep Space Network Deep space stations A network control center Space Network Tracking and data relay satellites A network control center Lunar Network Lunar relay orbiters Mars Network Mars relay orbiters Ground Network Tracking stations 8 Cross Support Service Element Basic Configuration A cross support service element has two interfaces (or two sets of interfaces). The interface (or the set of interfaces) closer to the space user element is called the space side interface The interface (or the set of interfaces) closer to the ground user element is called the ground side interface Space side interface of CSSE 1 Space User Element Space side interface of CSSE 2 CSSE S1 CSSE 2 Ground side interface of CSSE 1 Modified from IOAG / JAXA CSSA, Jan 2007, rev b Ground User Element Ground side interface of CSSE 2 9 SERVICE VIEW 10 Service View The Service View of this architecture is used to describe functional characteristics of the services provided by cross support service systems and cross support service elements. Specifically, it describes: Functional/performance characteristics of services, Methods and/or standards for using services, Methods and/or standards for managing services, Etc. Service Management Interface Service Utilization Management Service Provision Management Service Provision CSSE • • Service Interface Service Utilization User Element 11 Types of Cross-Support Services 1. Forward delivery services: • Command ra diation service • Command d elivery service 5. Video services: • Video broa dcast service • Video enha ncement service 2. Return delivery services: • Bit stre am service • Frame service • Packet service • Tele metry file service 6. Voice service 3. Tracking services: • Raw radio metric measurements service* • Validated radio metric data service • Delta-DOR/VLBI service • Optome tric data service • Position Determination Service 4. Time services: • Time dis tribution service • Time sync hroniz ation service • Spacecraft time correlation service 7. Beacon tone service 8. Ground communications services: • Ground c ommunications circuit service • Ground net work service 9. End-to-end network service 10. Launch service • Range Safety Service • Launch veh icle telemetry 11. LEOP services 12. Spacecraft emergency service 13. Spacecraft search/rescue services 14. Network security services * A type of service that is provided only in exceptional cases. 12 Example of Service View (CSSE Providing Delivery Services) Cross Support Service Element Online Forward Delivery Service Offline Forward Delivery Service Space User Element Ground User Element Online Return Delivery Service Offline Return Delivery Service Service Interfaces Modified from IOAG / JAXA CSSA, Jan 2007, rev b Service Interfaces 13 Service Attributes of CSSS/CSSE Each Service provided by a Cross Support Service System/Element has the following service attributes. Attribute Typical values Direction Forward, Return Delivery Mode (Latency) Online, Offline (Store & forward) Quality of service Timely, Complete, … Data units delivered Frames, Packets, Files, … Online data selection criteria SCID, VCID, APID, IP address, … Offline data selection criteria Reception times, Service Instance ID, … Ground side service protocol SLE, NASCOM, None, … 14 Example of Service View (Service Management) Cross Support Service Element Online Forward Delivery Service Offline Forward Delivery Service Cross Support Service Element for Provision Management Service Provision Management Service Utilization Management Online Return Delivery Service Offline Return Delivery Service Internal Service Control Interfaces Modified from IOAG / JAXA CSSA, Jan 2007, rev b Service Management Interface 15 Service Management Attributes of CSSS/CSSE Each Cross Support Service System/Element has the following service management attributes. Attribute Typical values Location of Service Provision Management Location, Network address, … Service Management Interactions Online protocol, File transfer, Email exchange, … Service Management Protocol SLE SM, SNMP, FTP, SMTP, … 16 Example: Service View of Deep Space Network DSCC Online Forward Delivery Service Space User Element Ground User Element Online Return Delivery Service Offline Return Delivery Service Other services were omitted from this diagram. Modified from IOAG / JAXA CSSA, Jan 2007, rev b 17 Example: Service Attributes of Deep Space Network Online Forward Delivery Service Forward or Return Forward Online or Offline Online Quality of Service Complete Data units delivered CLTUs Online Data selection criteria None Ground Side Service Protocol SLE FCLTU Online Return Delivery Service Forward or Return Return Online or Offline Online Quality of Service Complete or Timely Data units delivered Frames Online Data selection criteria VCID Ground Side Service Protocol SLE RAF, RCF Offline Return Delivery Service Forward or Return Return Online or Offline Offline Quality of Service Complete Data units delivered Frames Offline Data selection criteria VCID, Reception Time Ground Side Service Protocol SLE RAF, RCF 18 Example: Service View of Mars Network Mars Odyssey/MRO Online Forward Delivery Service Space User Element Offline Forward Delivery Service Ground User Element Online Return Delivery Service Offline Return Delivery Service Modified from IOAG / JAXA CSSA, Jan 2007, rev b 19 Example: Service Attributes of Mars Network Online Forward Delivery Service Online Return Delivery Service Forward or Return Forward Forward or Return Return Online or Offline Online Online or Offline Online Quality of Service Complete Quality of Service Complete Data units delivered Bits Data units delivered Bits Online Data selection criteria None Online Data selection criteria None Offline Forward Delivery Service Offline Return Delivery Service Forward or Return Forward Forward or Return Return Online or Offline Offline Online or Offline Offline Quality of Service Complete Quality of Service Complete Data units delivered Bits Data units delivered Bits Offline Data selection criteria None Offline Data selection criteria None 20 PHYSICAL VIEW 21 Physical View The Physical View of this architecture is used to describe the physical configuration and physical characteristics of cross support service systems and cross support service elements. Specifically, it describes: Physical location, Topology (connectivity), Physical medium for accessing, Etc. 22 An Example of Physical View Space User Element CSSS D CSSS S CSSE D1 CSSE S1 CSSE S3 CSSE S2 Modified from IOAG / JAXA CSSA, Jan 2007, rev b CSSE D2 Ground User Element 23 Physical Attributes of CSSS/CSSE Each Cross Support Service Element in a Cross Support Service System has the following physical attributes. Attribute Typical values Element type On the surface of xx, Orbiting around yy Location or Trajectory Geographical location, Orbital elements Space side access medium RF at Z-band, modulation, viewperiods, pointing params Dedicated wired line Ground side access medium RF at Z-band, modulation, viewperiods, pointing params Dedicated wired line Modified from IOAG / JAXA CSSA, Jan 2007, rev b 24 Example: Physical Attributes of Deep Space Network Goldstone DSCC Element type On the surface of the Earth Location Goldstone, California, USA Canberra DSCC Element type On the surface of the Earth Location Canberra, Australia Madrid DSCC Element type On the surface of the Earth Location Madrid, Spain There are attributes for each station (DSS) at each DSCC but they are omitted here. 25 COMMUNICATIONS VIEW 26 Communications View The Communications View of this architecture is used to describe communications protocols used for accessing services provided by cross support service systems and cross support service elements. Specifically, it describes: Protocol stacks for accessing services, Parameters of protocols used for accessing services, Etc. 27 An Example of Communications View Space User Element Cross Support Service Element Ground User Element User Element Online Forward Delivery Service User Element Transport Protocol Transport Protocol Transport Protocol Transport Protocol Network Protocol Network Protocol Network Protocol Network Protocol Data Link Protocol Data Link Protocol Data Link Protocol Data Link Protocol Physical Protocol Physical Protocol Physical Protocol Physical Protocol Modified from IOAG / JAXA CSSA, Jan 2007, rev b 28 Communications Attributes of CSSS/CSSE Each Cross Support Service Element has the following communications attributes. Attribute Typical values Ground side service protocol SLE RAF, CLTU, … Ground side transport protocol TCP, UDP, … Ground side network protocol IP, … Ground side data link protocol PPP, … Ground side physical protocol ISDN, … Space side transport protocol None, TCP, SCPS-TP, … Space side network protocol Space packet protocol, IP, … Space side data link protocol Space data link protocol, … Space side coding Turbo, Reed-Solomon, Convolutional, BCH, … Space side carrier frequency xxxxMHz Space side modulation QPSK, PSK-PM, BiPh-PM, … 29 Communications View of Deep Space Network Space User Element DSS Ground User Element User Element Any Delivery Service User Element Space Pkt Protocol Space Pkt Protocol Space Pkt Protocol Space Pkt Protocol SLE SLE Space Data Link Protocol Space Data Link Protocol TCP TCP IP IP CCSDS RF&Mod. CCSDS RF&Mod. ISDN or dedicated ISDN or dedicated Modified from IOAG / JAXA CSSA, Jan 2007, rev b 30 ENTERPRISE VIEW 31 Enterprise View The Enterprise View of this architecture is used to describe organizational and administrational features of the services provided by cross support service systems and cross support service elements. Specifically, it describes: Organizations that provide services, Facilities that deliver services, Policies to provide services, Contracts to use services, Activity for testing the service interface, e.g. compatibility tests and end-to-end tests Documents to use services, Pricing information, e.g. reimbursable, quid-pro-quo Etc. 32 An Example of Enterprise View Service Provision Enterprise CSSE S1 CSSE S2 Modified from IOAG / JAXA CSSA, Jan 2007, rev b CSSE S3 Service Utilization Enterprise Space User Element Ground User Element 33 Enterprise Attributes of CSSS/CSSE Each Cross Support Service System (and its Cross Support Service Elements) has the following enterprise attributes. Attribute Typical values Agency (or organization) that owns the CSSS NASA, ESA, ABC Space Communications Company, … Policies for providing services Available for any science mission, … Types of contracts to use the services Reimbursable, Cooperative, … Activity for testing the service interface Level of testing support, e.g. nominal and special tests Types of documents to use the services Service Agreement Document, Interface Control Document, … Pricing Information $xxx/hour + $yyy (fixed) (Others) 34 Analysis of JAXA Position Paper The JAXA CSSA approach provides a very useful framework for describing cross support architectures Definitions of terminology Viewpoints and representational methods Initial set of attributes Permits description of cross support architecture from several viewpoints Starting with enterprise level Arriving at a deep enough technical level Should support presentation of concepts to management and also allow adequate representation of interface details to define how they are to be actually implemented As presented (with mods) it adheres to the RASDS methodology The Service Catalog and attribute sets for interfaces in various views is a valuable extension, especially for this use Enterprise view with facility “cartoons”, ala DODAF OV-1 or SV-1 may be useful as top level view Provided by Peter Shames 3 April 2007 35 Today’s NASA Network Architecture Operational View Graphic (OV-1) DEEP SPACE NETWORK MISSIONS Planetary Explorations DSN SERVICES, INTERFACES, SPECTRUM Radio Astronomy SPACE NETWORK MISSIONS Space Telescope Earth Observing SN SERVICES, INTERFACES, SPECTRUM Space Station Airborne Experiments GROUND NETWORK MISSIONS Space Transportation GN SERVICES, INTERFACES, SPECTRUM National & DoD NASA Network Architecture Task DSN Status, Chuck Tang, Aerospace 23 September 2004 Educational Users 36 Deep Space Network – Interfaces System Interface Description (SV-1) USER SPACE LINK INTERFACES •Radio Astronomy •Goldstone Solar System Radar •VLBI Deep Space Missions 70 m L-Band S-Band X-Band 34 m HEF BWG X-Band 34 m BWG S-Band X-Band Ka-Band 34 m HS BWG S-Band 26 m S-Band Parkes Radio Observatory, Australia Australian Commercial Carrier MDSCC GDSCC CDSCC •DSN Resource Allocation •DSN Scheduling •DSN Predicts •DSN SOEs •Remote Operations Support Area (ROSA) •JPL Institutional Flight Projects Deep Space Operations Control Center (DSOCC) GSFC Flight Dynamics Facility JPL Navigation Services •Central Communications Terminal (CCT) •Advanced Multi-Mission Operations System (AMMOS) •Network Operations Control Team (NOCT) JPL Institutional LAN Flight Projects Commercial Circuits Inside JPL Firewall NASA Network Architecture Task DSN Status, Chuck Tang, Aerospace 23 September 2004 JPL Institutional Communications Building 171 (Contractor Facility - 1400 S. Shamrock Ave. Monrovia, CA) Radio Metric Data Conditioning (RMDC) 3 Commercial T-1 Circuits Inside JPL Firewall Reference: DSMS Telecomm Link Design Handbook (810-005) 37 Backup Materials 38 ISSUES AND NEXT STEPS 39 Technical Issues (1/3) There are space and ground users for the same service. We should consider how to specify these two users. (C. Sunshine) I think, for a service provided by a CSSE, we should define space user, ground user, and service utilization manager, and space side interface, ground side interface, and service management interface. What is the CSSE? Is it the whole ground station or the equipment that provides the service? (J. Pietras) In my opinion, a CSSE is any physical element that has cross support service interfaces. The user element only needs to know how to use the services through the service interfaces without any knowledge of the physical configuration of the element. 40 Technical Issues (2/3) There is dependency among views. That is, there are some attributes that depend on the values of attributes defined in other views. We need to consider how to describe relationships and dependency among views. We may also need to reconsider the definition and number of views. (W. Tai) I don’t have any clear response at the moment but will provide one in one month. 41 Technical Issues (3/3) We need to categorize services (e.g., layering and/or composition of services). (J. Pietras) I haven’t done this due to lack of time but will provide a draft material in a month. We need to define the function and a standard set of attributes for each of the services. (W. Tai) I haven’t done this due to lack of time but will provide a draft material in a couple of months. The policy and types of agency-to agency agreements should be elaborated so that they can be used in any MOU. (W. Tai) I agree that we need to define a standard set of attributes that can characterize any type of agency-to-agency agreement. I will prepare a draft material in one month. 42 Procedural Issues IOAG does not have any experience in developing standards, a procedure to develop them, or technical writers who can write good technical specifications. For the Cross Support Service Architecture, there is only an action item, but I do not believe that a high-quality standard can be generated only as a response to an action item. 43 PROPOSAL TO CREATE A JOINT IOAG-CCSDS WG We need to establish a special WG consisting of experts on cross support and standardization from both IOAG and CCSDS that will review the Cross Support Service Architecture document generated by IOAG and add any missing contents. The WG will then be transformed to develop the architecture standard specification to be published by CCSDS as a standard. JAXA/ISAS will lead the WG to review the IOAG cross support service architecture, in the form of an IOAG guidance document, and later develop the CCSDS cross support service architecture standard. This approach ensures continuity of the activity from the IOAG focus to the CCSDS focus while meeting the need of the IOAG stakeholders. 44 Tentative Schedule Milestone Date Activity and Milestone Mid 2-2007 Conduct 2 or 3-day working session between Yamada, Narita, and Tai to complete the key technical areas of the document. End of 2-2007 Complete the draft version. Issue the draft version to the IOAG members and the special WG for review. End of 2-2007 Distribute the template for the agency asset-specific service attribute table for the IOAG members to fill it out. End of 4-2007 IOAG members provide completed agency asset-specific service attribute tables End of 4-2007 Review completed by the IOAG members and the special WG. By IOAG-11 meeting 6-2007 date Complete the “final” version of the IOAG Cross Support Service Architecture document with accepted comments incorporated. IOAG-11 meeting Present the key features of the architecture and issues disposition. Obtain endorsement from the IOAG members. 45 Example: Physical View of Mars Network Mars Network Space User Element MRO Mars Odyssey Ground User Element 46 Example: Physical Attributes of Mars Network Mars Odyssey Element type Orbiting around Mars Orbit Orbital elements = xxxxxx MRO Element type Orbiting around Mars Orbit Orbital elements = yyyyyy 47 Communications Attributes of Deep Space Network Deep Space Station Ground side transport protocol TCP Ground side network protocol IP Ground side data link protocol PPP Ground side physical protocol ISDN, Dedicated Circuit Space side transport protocol None Space side network protocol Space packet protocol Space side data link protocol Space data link protocol (TM/TC/AOS) Space side coding (forward) BCH Space side coding (return) Turbo, R-S, Convolutional Space side carrier frequency (forward) 2025-2120MHz, 7145-7190MHz Space side carrier modulation (forward) PM 48 Communications View of Mars Odyssey Mars Odyssey Any Delivery Service Space Packet Protocol Space User Element Prox-1 Data Link Protocol Space Data Link Protocol Prox-1 Physical CCSDS RF&Mod. Ground User Element 49 Communications Attributes of Mars Odyssey Mars Odyssey Ground side transport protocol None Ground side network protocol Space packet protocol Ground side data link protocol Space data link protocol (TM/TC/AOS) Ground side coding (forward) BCH …. …. Space side transport protocol None Space side network protocol None Space side data link protocol Prox-1 data link protocol Space side coding (forward) BCH …. …. 50 Communications View of MRO MRO Any Delivery Service CFDP Space User Element Space Packet Protocol Prox-1 Data Link Protocol Prox-1 Physical Ground User Element Space Data Link Protocol CCSDS RF&Mod. 51 Communications Attributes of MRO MRO Ground side transport protocol CFDP Ground side network protocol Space packet protocol Ground side data link protocol Space data link protocol (TM/TC/AOS) Ground side coding (forward) BCH …. …. Space side transport protocol None Space side network protocol None Space side data link protocol Prox-1 data link protocol Space side coding (forward) BCH …. …. 52