© 2004 The MITRE Corporation. All rights reserved Consultative Committee for Space Data Systems Cislunar Networking Working Group Keith Scott JPL Cislunar Workshop 16 June 2004 Pasadena, CA

© 2004 The MITRE Corporation. All rights reserved 2 Background n MITRE –Not for profit, non-competitive, chartered in the public interest n 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: n DOD n FAA n IRS –Networking Center n Tactical military networks, Navy ForceNet, NCW, SATCOM, MobileIP, … n 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

© 2004 The MITRE Corporation. All rights reserved 3 CCSDS n Consultative Committee for Space Data Systems (CCSDS) –Members: Various nations’ space agencies n They fund people to work on CCSDS –Develops international standards for communicating with and among spacecraft n Standards enable (international) cross-support n Pool the small market for space communications hardware/software n Adopt, adapt, develop n Product: standards, some prototype implementations –Six main areas within CCSDS: n System Engineering Spacecraft On-board Interfaces n Space Internetworking Space Link ­Cislunar Working Group Cross Support n Mission Operations and Information Management

© 2004 The MITRE Corporation. All rights reserved 4 Background (cont’d) –Cislunar Working Group n Support upcoming lunar exploration (human / robotic) n If at all possible, re-use technology for Mars exploration n Held a Birds of a Feather (BOF) Meeting 14 May 2004 n Commitments of international support

© 2004 The MITRE Corporation. All rights reserved 5 Motivation for Cislunar Working Group n Increased interest in human and robotic exploration of the Moon and Mars n Near-Earth comms: can be “Internet-like” n Deep-Space: –CCSDS Telemetry / Telecommand (TM / TC) –CCSDS File Delivery Protocol (CFDP) –Delay Tolerant Networking (DTN) n What about lunar distances? (~2.5 sec RTT) –End-to-End TCP sees severe performance limitations –Human exploration comes with stringent requirements –Very high rate, voice/video (HDTV), reliability, availability –Humans want ‘everyday’ applications: , web, …

© 2004 The MITRE Corporation. All rights reserved 6 Cislunar Working Group n Kickoff meeting 14 May 2004 at Spring meetings –International participation (ESA, BNSC, CSA, …) –Presentations on: n Environment n Architectures n CCSDS and other protocols / capabilities –Draft Charter n Current Status –CCSDS has voted to form the working group –In the process of allocating resources

© 2004 The MITRE Corporation. All rights reserved 7 Cislunar WG Work Items n 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) n 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) n Research new protocols for adoption by CCSDS* –IETF standards (SCTP, LEMONADE, DCCP, and MIDCOM working groups, …) *Probably not in time for 2008 lunar mission.

© 2004 The MITRE Corporation. All rights reserved Requirements

© 2004 The MITRE Corporation. All rights reserved 9 Lunar Communications Requirements n 1969 Moon shot –Voice –Video –Minimal Data n 2020 Moon shot –Voice –Videoconference –HDTV downlink –“Everyday” applications ( , web, …) –Operation in intermittently- connected environments? –Tele-operation of robots –Lots of “stuff” n Networked architecture, not a bunch of point-to-point links 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.

© 2004 The MITRE Corporation. All rights reserved 10 Networked Architecture n Efficient use of links, especially as the number of users increases vs. n Support for disconnected operations –What if there’s no end-to-end path? n Simplified management: get away from “one spacecraft, one (DTE) link” ff

© 2004 The MITRE Corporation. All rights reserved 11 n Mission Critical –24x7 voice for human exploration n Robust n Extensible n Relay Comms n High rate –HDTV –Big science (SAR, multi-spectral imaging, …) n Lots of “stuff” –Networked architecture, not a bunch of point-to-point links

© 2004 The MITRE Corporation. All rights reserved 12 Link and Physical Technologies n , etc. –Certainly worth exploring n Software defined radios –Great; buys future expandability / interoperability –Choose particular protocol later –Issues: n Frequency n Achievable data rate n Optical –Needs good link layer protocol / coding, especially for DTE

© 2004 The MITRE Corporation. All rights reserved Baseline Architecture

© 2004 The MITRE Corporation. All rights reserved 14 Communications Links Adapted from “LDRM Communication Operations Concept (Laura Hood, JSC) Surface EVA(s) Lunar Rover Lunar Lander Science Inst. Lunar Surface Earth Lunar Vicinity Lunar Orbiters Camera Earth

© 2004 The MITRE Corporation. All rights reserved 15 Networking Services Space Transport Services Space Application Services End-to-End Space Applications Space Transport Services Space Application Services End-to-End Space Applications End-to-End Networking Architecture Terrestrial Link Services Terrestrial Link Services Space Link Services Onboard Link Services Onboard Link Services

© 2004 The MITRE Corporation. All rights reserved 16 Terrestrial Link Services Terrestrial Networking Services Terrestrial Transport Services Space Application Services End-to-End Space Applications Onboard Link Services Onboard Transport Services Space Application Services End-to-End Space Applications Terrestrial Transport Services Space Transport Services Space Transport Services Onboard Transport Services Space Networking Services Onboard Networking Services Terrestrial Link Services Space Link Services Space Link Services Onboard Link Services Gatewayed Transport / Networking Architecture Ground Station Gateway Internet Onboard Gateway App

© 2004 The MITRE Corporation. All rights reserved CCSDS Protocols

© 2004 The MITRE Corporation. All rights reserved 18 Space Networking Services Space Networking Services Space Transport Services Space Application Services TCP CCSDS AOS, TM, TC CCSDS AOS/TM/TC Coding CCSDS RF & Mod CCSDS Proximity 1 CCSDS Prox-1 Coding CCSDS RF & Mod Currently Unspecified End-to-End Space Applications CCSDS Path IPSec, CCSDS SP FTP, CCSDS FP CFDP UDP IPv4, IPv6, CCSDS NP Space Long HaulSpace ProximitySpace Surface

© 2004 The MITRE Corporation. All rights reserved 19 Protocols Space Network (TDRS) Deep Space Network (DSN) Ground Network (NASA /commercial) Surface EVA(s) Lunar Rover Lunar Lander Science Inst. Lunar Surface Earth Lunar Vicinity Lunar Orbiters Camera Earth Surface Proximity Link CCSDS Advanced Orbiting Sytems (AOS), TC/TM CCSDS Prox-1 [CCSDS TC/TM CCSDS AOS] [CCSDS TC/TM CCSDS AOS] [CCSDS TC/TM CCSDS AOS] Existing Ground Equip. Existing Radios

© 2004 The MITRE Corporation. All rights reserved 20 Existing CCSDS Capabilities n Availability –Commercial companies support CCSDS protocols n Speed –CCSDS TC/TM/AOS Telemetry Processors available up to 400Mbps –CCSDS Prox-1 implementation speeds? n Application support –Support for streaming applications (voice) –Support for applications built over IPv4, IPv6 n Cross-Support –Prox-1 cross-support demonstrated at Mars image.gsfc.nasa.gov/publication/ document/dmr/image_dmr_5.html

© 2004 The MITRE Corporation. All rights reserved New Protocols

© 2004 The MITRE Corporation. All rights reserved 22 Related Technologies n Lemonade –Enhancements and profiles of Internet submission, transport, and retrieval protocols to facilitate operation on platforms with constrained resources, or communications links with high latency or limited bandwidth n Datagram Congestion Control Protocol (DCCP) –A minimal general purpose transport-layer protocol providing: n setup, maintenance and teardown of unreliable packet flows n congestion control of those flows. n Stream Control Transmission Protocol (SCTP) –Think of it as “TCP+”: message boundaries, multiple streams, support for multi-homing, … n Middlebox Communications (Midcom) –How end hosts can discover and interact with proxies in the middle of the network n IP-over-DVB (and other link technologies)

© 2004 The MITRE Corporation. All rights reserved 23 Participation n CCSDS Information (participation, meeting schedule): – n Cislunar WG mailing list: – n Me:

© 2004 The MITRE Corporation. All rights reserved 24 Conclusions n Baseline architecture –Looking at both end-to-end and gatewayed architectures –CCSDS Protocol Suite n Flight-proven hardware and software n Supports target application set n CCSDS protocols installed and running in ground stations n Standards, interoperability, international cross-support n Lunar Relay Orbiter Recommendations –Networked architecture. Go to at least layer 3 (network) in the spacecraft n Because we want to get away from “one spacecraft, one DTE link” n 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-1 protocols for Earth and Lunar element comms., respectively n Existing commercial hardware, Software Defined Radio, …

© 2004 The MITRE Corporation. All rights reserved 25 Strawman LRO Capabilities Surface EVA(s) Lunar Rover Lunar Lander Science Inst. Lunar Surface Earth Lunar Vicinity LRO Camera Earth Surface Proximity Link CCSDS Advanced Orbiting Sytems (AOS) CCSDS Prox-1

© 2004 The MITRE Corporation. All rights reserved Questions?

© 2004 The MITRE Corporation. All rights reserved 27 Backups

© 2004 The MITRE Corporation. All rights reserved 28 Some Data Points n Earth-Moon distance is 384,748 km (~1.28s one-way) n Earth-Mars distance varies between ~4 minutes and ~20 minutes (one-way)

© 2004 The MITRE Corporation. All rights reserved 29 IETF Datagram Congestion Control Protocol (dccp) n 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.

© 2004 The MITRE Corporation. All rights reserved 30 IETF LEMONADE n Lemonade is tasked to provide a set of enhancements and profiles of Internet 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 protocols in use on the Internet, so that these environments and more traditional Internet users have access to a seamless service.

© 2004 The MITRE Corporation. All rights reserved 31 IETF SCTP (RFC2960) n 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. n The design of SCTP includes appropriate congestion avoidance behavior and resistance to flooding and masquerade attacks.

© 2004 The MITRE Corporation. All rights reserved 32 Middlebox Architectures n 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.' n SCPS-TP Gateways

© 2004 The MITRE Corporation. All rights reserved 33 Space Networking Services Space Transport Services Space Long-Haul Data Link Space Long-Haul Coding Space Long-Haul Channel Space Proximity Data Link Space Proximity Coding Space Proximity Channel Space Surface Data Link Space Surface Coding Space Surface Channel End-to-End Space Applications Space Application Services Space Networking Services Space Link Services Space Long HaulSpace ProximitySpace Surface SPACE PROTOCOL MODEL

© 2004 The MITRE Corporation. All rights reserved 34 End-to-End Data Flow

© 2004 The MITRE Corporation. All rights reserved 35 Subnet Path Service Bitstream Service Virtual Channel Access Service Virtual Channel Data Unit Insert Service Physical Channel Virtual Channel Subnet Multiplexing Bit stream Packet Transfer Onboard NetworkSpace Link Subnetwork IP Internet Path Protocol Internet Service Application Services Encap. Encapsulation Service Internet Packet Transfer End-to-End Data Flow , Web, Chat Voice CCSDS Internet Service: Provided IP or IP-like end-end data transfer CCSDS Path Service: Provides efficient managed end-end data transfer CCSDS Encapsulation Service: Wraps delimited data units for space link transfer 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 CCSDS Virtual Channel Data Unit Service: Interleaves CCSDS Frames from different spacecraft CCSDS Insert Service: Transfers small block of octets isochronously CCSDS Bitstream Service: Relays a stream of bits across link via CCSDS Frame