1. April 20051 Space Link Services AREA REPORT 15 April 2005

2. April 20052 SLS AREA REPORT CONTENTS A.CURRENTLY ACTIVE WGs AND BOFs WITHIN AREA B.SUMMARY TECHNICAL STATUS OF EACH WG & BOF C.CROSS-AREA TECHNICAL ISSUES D.OTHER ISSUE AND CONCERNS E.PROPOSED AREA RESOLUTIONS/ACTION ITEMS SLS Area WGs meet from 11 to 14 April. New Res & Recs will be reviewed at the SLS Plenary on 15 April.

3. April 20053 1.SLS-RFM - RF & Modulation WG 2.SLS-RNG – Ranging WG 3.SLS-TCC – Telecommand Channel Coding WG 4.SLS-C&S – Coding & Synchronization WG 5.SLS-LDPC - New Codes : Low Density Parity Check Codes BOF 6.SLS-LEC - Long Erasure Codes BOF 7.SLS-SLP – Space Link Protocols WG 8.SLS-PROX – Proximity Links-1 Build-2 WG 9.SLS-DC – Data Compression WG 10.SLS-HDRU – High Data Rate Uplink A.LIST OF CURRENT WGs AND BOFs WITHIN AREA SLS AREA REPORT

4. April 20054 B.SUMMARY TECHNICAL STATUS 1.SLS - RF&Modulation WG Goal: align 401.0-B with WRC-03, SFCG-23/24/25 Working Group Status: Active Working Group Summary Situation: Working Group Summary progress: Three recommendations processed. Rec 2.4.18 awaiting SFCG decision in Oct 2005. Three last items are GMSK imbalance, 7/26 GHz turnaround ratio and data rate stability for suppressed-carrier modulation. Work completion Nov 2005. status:OKCAUTIONPROBLEM comment:Good progress SLS AREA REPORT

5. April 20055 B.SUMMARY TECHNICAL STATUS 1.SLS-RFM WG Problems and Issues: Pink sheets produced Nov’04 are still not published for agency review Green Book containing Earth station characteristics (411.0-G-3) will not be maintained any longer CMC decision)  Taken over by IOAG but commitment of IOAG not clear Outputs: RES + AI publication of Pink sheet 2.4.11 for agency review RES + AI publication of Red Rec 2.5.1.B for agency review RES + AI deletion of Rec 2.6.12 SLS AREA REPORT

6. April 20056 B.SUMMARY TECHNICAL STATUS 2.RANGING WG Goal: issue blue book on novel ranging techniques Working Group Status: Active Working Group Summary Situation: Working Group Summary progress:  Independent theoretical analysis and simulation results on most regenerative PN ranging specs available from two Agencies;  Five different ranging schemes identified as possible candidates for regenerative ranging; status:OKCAUTIONPROBLEM comment:Good progress SLS AREA REPORT

7. April 20057 B.SUMMARY TECHNICAL STATUS 2.RANGING WG Working Group Summary progress (cont.):  White book (Issue 1) to be issued by July 2005 is being written with focus on regenerative PN codes;  Transparent PN codes will be addressed after WB issue 1 is out.  Simulation work and breadboarding initiated with one agency. Problems and Issues:  None so far SLS AREA REPORT

8. April 20058 B.SUMMARY TECHNICAL STATUS 3.SLS-TCC: Telecommand Channel Coding WG Goal: Development of a Telecommand Channel Coding Green Book. Working Group Status: Active Working Group Summary Situation: Working Group Summary progress:  Green Book undergoing final WG review.  Rids to BB 231 processed Outputs RES + AI publish Pink Sheets on BB 231. RES indicates that draft GB is available in support to pink sheets review status:OKCAUTIONPROBLEM comment: Good progress SLS AREA REPORT

9. April 20059 B.SUMMARY TECHNICAL STATUS 4.SLS-C&S: Coding & Synchronization WG (1) Goal : - Issue TM Channel Coding GB - Issue new codes experimental (orange) book(s) Working Group Status: Active Working Group Summary Situation: Working Group Summary progress :  See next slide status:OKCAUTIONPROBLEM comment:X SLS AREA REPORT

10. April 200510 B.SUMMARY TECHNICAL STATUS 4.SLS-C&S: Coding & Synchronization WG (2) Telemetry Channel Coding Green Book formating problems resolved by secretariat. To be published soon. One RES on book title & numbering Orange Book on GSFC LDPC Codes: Book was discussed, update to be performed according to comments received. Outputs RES + AI to change title and numbering of TM Channel Coding GB Future Work The WG should take-up the two new proposed Orange Books (see New Codes BOF report) SLS AREA REPORT

11. April 200511 B.SUMMARY TECHNICAL STATUS 5.SLS- LDPCC: New Codes : LDPCC BOF (1/2) Goal: Identify requirements for future codes, define evaluation criteria and possibly select a family of Codes according to identified requirements. BOF Status: Active BOF Summary Situation: Working Group Summary progress:  Requirements & Evaluation Criteria Doc was produced by UniBo and was reviewed and updated at April’05 meeting status:OKCAUTIONPROBLEM comment: X SLS AREA REPORT

12. April 200512 B.SUMMARY TECHNICAL STATUS 5.SLS- LDPCC: New Codes : LDPCC BOF (2/2) Working Group Summary progress:  NASA proposed standardisation of a set of LDPC codes or alternatively as a fall-back specifically two codes (rate ½ & 7/8); no consensus reached  Update of RECD showed further divergences between agencies approaches; no consensus reached  NASA proposed production of a second Orange Book on JPL family of LDPCC  ESA proposed to submit an Orange Book reporting on ESA work on SCCC Conclusion:  Goal has been achieved as far as identification of requirements from each agency is concerned. Currently no consensus on common needs.  Decision not to proceed with the BOF  Issue can be readressed in the future if supported by well-identified mission needs SLS AREA REPORT

13. April 200513 B.SUMMARY TECHNICAL STATUS 6.SLS-LEC: Long Erasure Codes (‘tornado codes’) BOF Goal: Make, if conclusive, a proposal for the creation of a WG on application of long erasure-correction codes. BOF Status : Active BOF Summary Situation: Working Group Summary progress:  Work restarted by NASA. ESA work ongoing.  LEC outage mitigation capabilities have been identified. To be checked at next meeting against practical operational scenarios.  Decision on creation of WG to be taken after Fall’05 meeting. status:OKCAUTIONPROBLEM comment: work in progress SLS AREA REPORT

14. April 200514 B.SUMMARY TECHNICAL STATUS 7.SLS-SLP : Space Data Link Protocols WG (1/2) Goal: - Adapt, Adopt, and Create link layer Protocols for space data systems - Develop Link Layer Green Books for CCSDS Link Layer Protocols Working Group Status: Active Working Group Summary Situation: Working Group Summary progress:  Pink Sheet to Space Link Identifiers Blue Book to add Prox-1 Port ID Values. Under agency review by May 30, 2005.  Pink Sheet to AOS Space Data Link Protocol Blue Book to augment frame sequence counter. Under agency review by May 30, 2005.  RED-2 Version of the Encapsulation Packet Service to modify the header to be 32-bit compatible. Under agency review by May 30, 2005.  Overview of Space Link Protocols GB and the Space Data Link Protocol GB submitted to secretariat for publishing on web site.  Current work on Reviewing the Draft Proximity-1 Space Link Protocol GB. New edition due by Sept. 2005 status:OKCAUTIONPROBLEM comment:Work in progress SLS AREA REPORT

15. April 200515 B.SUMMARY TECHNICAL STATUS 7.SLS-SLP : Space Data Link Protocols WG (2/2) Problems and Issues:  Need further iteration on the Proximity-1 GB to ensure that non-expert users can understand it  Need a mechanism to display onto the CCSDS web site the Executive Summaries of the CCSDS link layer protocols that Tim Ray has written to date (COP-P, AOS, TC, TM, etc) also including the TBD Proximity-1 Executive Summary Is there any way Frequently Asked Questions (FAQ)s can be placed on the CCSDS Web Site concerning the existing specifications as an introduction of the blue books for the user? SLS AREA REPORT

16. April 200516 B.SUMMARY TECHNICAL STATUS 8.Prox-1-Build-2 WG (1/2) Goal: Update the Proximity-1 Space Link (3) books to be in sync with the first generation of Prox-1 spacecrafts Working Group Status: Active Working Group Summary Situation:  The only remaining item in this WG, is to resolve the following physical layer requirements: 1) data rate offset, 2) short and long term data rate stability, 3) symbol to symbol stability. Working Group Summary progress :  Pink Sheets created for Prox-1 Physical Layer BB to cover those three requirements above. Under agency review. status:OKCAUTIONPROBLEM comment:Deadlock on pink sheets SLS AREA REPORT

17. April 200517 Prox-1-Build-2 WG (2/2): –Problems and Issues: BNSC and NASA/JPL do not agree with the value for the symbol to symbol deviation in the proposed requirements. Action on NASA/JPL to provide results to the WG that shows that dithering provides slight (~.1 dB) degradation in performance by July 1, 2005 Action on BNSC to provide results to the WG that shows that dithering provides a large performance hit (~1.5dB) degradation in performance by July 1, 2005.

18. April 200518 9.Data compression WG (1/5) Goal: Specify an image compression algorithm fulfilling identified space mission requirements Develop a subsequent recommendation together with the supporting information (performances, usage, reference software, etc …). Working Group Status: Active X Idle ____ Working Group Summary Situation: status:OKCAUTIONPROBLEM comment:Good progress SLS AREA REPORT

19. April 200519 Data compression WG (2/5) Working Group Summary progress: Red book issue 1 has been reviewed : 23 RIDS received and closed.  Prepare RB-2 Green book is being assembled; editing leadership has been split among WG members; major chapters completed. target : BB & GB release at the same date (cf. planning);  Complete GB draft and WG review Cross verification of recommendation being conducted: 4 independent S/W implementations, one of these will be chosen as reference software, needed for compliance testing and performance evaluation.; 3 S/W under verification with 50% completed  Complete S/W cross-verification  Total 14 WG Action Items created SLS AREA REPORT

20. April 200520 Data compression WG (3/5) Problems and Issues: WG decides to strictly separate compression and data transport issues. Synchronization markers will not be provided by the compression rec. : for bitstream oriented services, it will be up to the users to insert synchronization marker aligned with each compressed segment. Reference software should be part of the final recommendation, therefore it is desirable that it is available from the CCSDS website together with the BB, as an open source software with appropriate S/W license. WG appreciates significant contributions from ESA in the past and invites continued ESA participation SLS AREA REPORT

21. April 200521 Data compression WG (4/5) Planning : Complete GREEN BOOK draft July, 2005 Complete S/W cross-verification July, 2005 Issue RED BOOK-2, July, 2005 Release reference S/W, October, 2005 Issue GREEN BOOK, October, 2005 Issue BLUE BOOK, October, 2005 Begin agency review of 121.0-B-1: Lossless Data Compression Blue Book issued 1997 for either confirmation, update or retirement, October, 2005 Decision on new Compression BOF, Fall meeting 2005 SLS AREA REPORT

22. April 200522 Data compression WG (5/5) Outputs: RES Reference SW will be owned by an external body and made available on an external web site as an open source Long- term commitment for SW availability is questionable RES Request CESG to inform CCSDS agencies to provide input on future needs for data compression (e.g. multi-/hyper- spectral, radar, …..) in the Fall meeting delete RES Request CESG to call for reinforced participation to DC WG for completion of Image Compression Book. SLS AREA REPORT

23. April 200523 B.SUMMARY TECHNICAL STATUS 10.SLS- High Rate Uplink BOF (1/2) Goal: Space agencies are demanding higher uplink data rates. Provide CCSDS recommendations for high rate uplink missions addressing RF&Mod, channel coding, and link layer protocol issues. Working Group Status: BOF Charter Drafted and Approved by AD Working Group Summary Situation: Working Group Summary progress:  Need amongst agencies is to be identified. BOF charter approved by SLS-AD and distributed via SLS-area CCSDS web site. status:OKCAUTIONPROBLEM comment:BOF charter approval SLS AREA REPORT

24. April 200524 B.SUMMARY TECHNICAL STATUS 10.SLS- High Rate Uplink BOF (2/2) SLS RES [SLS-R-0504-001] : CESG to survey agencies on their need for high data rate capability for E-S links in the future. delete SLS AREA REPORT

25. April 200525 A.Proximity-1 Physical Layer Data Rate Stability Requirements (RF& MOD and Prox-1-Build-2)  Concensus on the average stability requirement (long and short term) as well as data rate offset requirement  No agreement on the value for the symbol to symbol difference C.INTRA-AREA TECHNICAL ISSUES SLS AREA REPORT

26. April 200526 A.Secure Communications Joint meeting SLS Area – Security WG held 11 April  Discussion on potential BOF creation for secure RF&modulation techniques and secure Data Link protocols  Interest of agencies for common (internationaly standardized and open) solutions still questionable in this field although agencies have agreed on a common set of threats to protect against C.CROSS-AREA TECHNICAL ISSUES SLS AREA REPORT

27. April 200527 D.OTHER ISSUES AND CONCERNS - SLS AREA REPORT

28. April 200528 Next SLS Area Meetings Fall’05 Sept.05 / Atlanta not possible for all WGs WGs meetings spread over the Sept – Nov period SLS ‘Plenary’ by email/telecon early Dec’05 Essential cross-WG meetings are secured SLS AREA REPORT

29. April 200529 Resolutions and Action Items Resolutions reference format SLS-WWW-R-0504-nnn Action Items reference format SLS-WWW-A-0504-nnn WWW:WG code SLS AREA REPORT