Consultative Committee for Space Data Systems Cislunar Networking Working Group

1. Consultative Committee for Space Data SystemsCislunar Networking Working Group Keith Scott JPL Cislunar Workshop 16 June 2004 Pasadena, CA

2. Background • MITRE • Not for profit, non-competitive, chartered in the public interest • Work in partnership with government, applying systems engineering and advanced technology to issues of national importance • The MITRE corporation runs three Federally Funded Research and Development Centers: • DOD • FAA • IRS • Networking Center • Tactical military networks, Navy ForceNet, NCW, SATCOM, MobileIP, … • Previous and current work with NASA/DoD on space communications protocols and tactical applications • Asked by Code-M to lead CCSDS working group on cislunar and in-situ communications

3. CCSDS • Consultative Committee for Space Data Systems (CCSDS) • Members: Various nations’ space agencies • They fund people to work on CCSDS • Develops international standards for communicating with and among spacecraft • Standards enable (international) cross-support • Pool the small market for space communications hardware/software • Adopt, adapt, develop • Product: standards, some prototype implementations • Six main areas within CCSDS: • System Engineering Spacecraft On-board Interfaces • Space Internetworking Space Link • Cislunar Working GroupCross Support • Mission Operations andInformation Management

4. Cislunar Working Group • Kickoff meeting 14 May 2004 at Spring meetings • International participation (ESA, BNSC, CSA, …) • Presentations on: • Environment • Architectures • CCSDS and other protocols / capabilities • Draft Charter • Current Status • CCSDS has voted to form the working group • In the process of allocating resources

5. Cislunar WG Work Items • Define baseline communications architecture to support lunar and in-situ communications • Human and robotic • Reuse (of existing technology, of this technology into future environments, e.g. Mars in-situ) • Examine existing CCSDS protocols to determine how they can be applied to the baseline architecture • Centered on network, transport layers • Update existing standards where appropriate • Issues discovered related to link and application protocols will be referred to relevant CCSDS areas (Space Link Services, Applications) • Research new protocols for adoption by CCSDS* • IETF standards (SCTP, LEMONADE, DCCP, and MIDCOM working groups, …) *Probably not in time for 2008 lunar mission.

6. Lunar Communications Requirements • 1969 Moon shot • Voice • Video • Minimal Data • 2020 Moon shot • Voice • Videoconference • HDTV downlink • “Everyday” applications (email, web, …) • Operation in intermittently- connected environments? • Tele-operation of robots • Lots of “stuff” • Networked architecture, nota bunch of point-to-pointlinks WASHINGTON (CNN) -- Saying "the desire to explore and understand is part of our character," President Bush Wednesday unveiled an ambitious plan to return Americans to the moon by 2020 and use the mission as a steppingstone for future manned trips to Mars and beyond.

7. Networked Architecture • Efficient use of links, especially as the number of users increases vs. • Support for disconnected operations • What if there’s no end-to-end path? • Simplified management: get away from “one spacecraft, one (DTE) link” f f

8. Communications Links Lunar Surface Lunar Lander Lunar Rover Surface EVA(s) Science Inst. Camera Lunar Vicinity Lunar Orbiters Earth Earth Adapted from “LDRM Communication Operations Concept (Laura Hood, JSC)

9. End-to-End Networking Architecture End-to-End Space Applications End-to-End Space Applications Space Application Services Space Application Services Space Transport Services Space Transport Services Networking Services Terrestrial Link Services Terrestrial Link Services Space Link Services Onboard Link Services Onboard Link Services

10. Gatewayed Transport / Networking Architecture End-to-End Space Applications End-to-End Space Applications Space Application Services Space Application Services Space Transport Services Onboard Transport Services Terrestrial Transport Services Terrestrial Transport Services Space Transport Services Onboard Transport Services Terrestrial Networking Services Space Networking Services Onboard Networking Services Terrestrial Link Services Terrestrial Link Services Space Link Services Space Link Services Onboard Link Services Onboard Link Services App App Ground Station Gateway Onboard Gateway Internet

11. End-to-End Space Applications Space Application Services FTP, CCSDS FP CFDP Space Transport Services UDP TCP Space Networking Services CCSDS Path IPSec, CCSDS SP IPv4, IPv6, CCSDS NP Space Networking Services CCSDS AOS, TM, TC CCSDS Proximity 1 Currently Unspecified CCSDS AOS/TM/TC Coding CCSDS Prox-1 Coding Currently Unspecified CCSDS RF & Mod CCSDS RF & Mod Currently Unspecified Space Long Haul Space Proximity Space Surface

12. Protocols Lunar Surface Lunar Lander Surface Proximity Link Lunar Rover Surface EVA(s) Science Inst. Camera CCSDS Prox-1 Lunar Vicinity CCSDS Advanced Orbiting Sytems (AOS), TC/TM Lunar Orbiters Existing Radios Earth Earth Existing Ground Equip. [CCSDS TC/TM CCSDS AOS] Ground Network (NASA /commercial) Space Network (TDRS) Deep Space Network (DSN) [CCSDS TC/TM CCSDS AOS] [CCSDS TC/TM CCSDS AOS]

13. Existing CCSDS Capabilities • Availability • Commercial companies support CCSDS protocols • Speed • CCSDS TC/TM/AOS Telemetry Processors available up to 400Mbps • CCSDS Prox-1 implementation speeds? • Application support • Support for streaming applications (voice) • Support for applications built over IPv4, IPv6 • Cross-Support • Prox-1 cross-support demonstrated at Mars image.gsfc.nasa.gov/publication/ document/dmr/image_dmr_5.html

14. Related Technologies • Lemonade • Enhancements and profiles of Internet email submission, transport, and retrieval protocols to facilitate operation on platforms with constrained resources, or communications links with high latency or limited bandwidth • Datagram Congestion Control Protocol (DCCP) • A minimal general purpose transport-layer protocol providing: • setup, maintenance and teardown of unreliable packet flows • congestion control of those flows. • Stream Control Transmission Protocol (SCTP) • Think of it as “TCP+”: message boundaries, multiple streams, support for multi-homing, … • Middlebox Communications (Midcom) • How end hosts can discover and interact with proxies in the middle of the network • IP-over-DVB (and other link technologies)

15. Participation • CCSDS Information (participation, meeting schedule): • http://www.ccsds.org • Cislunar WG mailing list: • http://mailman.ccsds.org/cgi-bin/mailman/listinfo/sis-csi • Me: • kscott@mitre.org

16. Conclusions • Baseline architecture • Looking at both end-to-end and gatewayed architectures • CCSDS Protocol Suite • Flight-proven hardware and software • Supports target application set • CCSDS protocols installed and running in ground stations • Standards, interoperability, international cross-support • Lunar Relay Orbiter Recommendations • Networked architecture. Go to at least layer 3 (network) in the spacecraft • Because we want to get away from “one spacecraft, one DTE link” • If at all possible, provide the ability to experiment with technologies like CFDP and DTN to support communications over disconnected paths • Support CCSDS AOS and Prox-1protocols for Earth and Lunar element comms., respectively • Existing commercial hardware, Software Defined Radio, …

17. Strawman LRO Capabilities Lunar Surface Lunar Lander Surface Proximity Link Lunar Rover Surface EVA(s) Science Inst. Camera CCSDS Prox-1 Lunar Vicinity CCSDS Advanced Orbiting Sytems (AOS) LRO Earth Earth

18. Questions?

19. Backups

20. Some Data Points • Earth-Moon distance is 384,748 km (~1.28s one-way) • Earth-Mars distance varies between ~4 minutes and ~20 minutes (one-way)

21. IETF Datagram Congestion Control Protocol (dccp) • The Datagram Control Protocol working group is chartered to develop and standardize the Datagram Congestion Control Protocol (DCCP). DCCP is a minimal general purpose transport-layer protocol providing only two core functions: • The establishment, maintenance and teardown of an unreliable packet flow. • Congestion control of that packet flow.

22. IETF LEMONADE • Lemonade is tasked to provide a set of enhancements and profiles of Internet email submission, transport, and retrieval protocols to facilitate operation on platforms with constrained resources, or communications links with high latency or limited bandwidth. A primary goal of this work is to ensure that those profiles and enhancements continue to interoperate with the existing Internet email protocols in use on the Internet, so that these environments and more traditional Internet users have access to a seamless service.

23. IETF SCTP (RFC2960) • SCTP is a reliable transport protocol operating on top of a connectionless packet network such as IP. It offers the following services to its users: • acknowledged error-free non-duplicated transfer of user data, • data fragmentation to conform to discovered path MTU size • sequenced delivery of user messages within multiple streams, with an option for order-of-arrival delivery of individual user messages • optional bundling of multiple user messages into a single SCTP packet • network-level fault tolerance through supporting of multi-homing at either or both ends of an association. • The design of SCTP includes appropriate congestion avoidance behavior and resistance to flooding and masquerade attacks.

24. Middlebox Architectures • IETF midcom working group • As trusted third parties are increasingly being asked to make policy decisions on behalf of the various entities participating in an application's operation, a need has developed for applications to be able to communicate their needs to the devices in the network that provide transport policy enforcement. Examples of these devices include firewalls, network address translators (both within and between address families), signature management for intrusion detection systems, and multimedia buffer management. These devices are a subset of what can be referred to as 'middleboxes.' • SCPS-TP Gateways

25. End-to-End Space Applications Space Application Services Space Transport Services Space Networking Services SPACE PROTOCOL MODEL Space Networking Services Space Link Services Space Long-Haul Data Link Space Proximity Data Link Space Surface Data Link Space Long-Haul Coding Space Proximity Coding Space Surface Coding Space Long-Haul Channel Space Proximity Channel Space Surface Channel Space Long Haul Space Proximity Space Surface

26. End-to-End Data Flow

27. CCSDS Multiplexing Service: Switches packets in/out of CCSDS Frames CCSDS Virtual Channel Access Service: Relays a block of octets across link via CCSDS Frame End-to-End Data Flow CCSDS Path Service: Provides efficient managed end-end data transfer CCSDS Encapsulation Service: Wraps delimited data units for space link transfer CCSDS Bitstream Service: Relays a stream of bits across link via CCSDS Frame CCSDS Virtual Channel Data Unit Service: Interleaves CCSDS Frames from different spacecraft CCSDS Internet Service: Provided IP or IP-like end-end data transfer Email, Web, Chat Application Services Path Service Bitstream Service Virtual Channel Access Service Packet Transfer Internet Path Protocol Packet Transfer Virtual Channel Data Unit CCSDS Insert Service: Transfers small block of octets isochronously Internet Service Internet Internet Voice Insert Service Encapsulation Service IP Subnet Subnet Subnet Subnet Encap. Multiplexing Bit stream Virtual Channel Physical Channel Onboard Network Space Link Subnetwork