RFC 829

Packet Satellite Technology Reference Sources 🛰️✨

okay bestie, the title block first! 🎀 This is RFC 829, from the Network Working Group, dated November 1982. It was written by Vinton G. Cerf at DARPA (the Defense Advanced Research Projects Agency). There's no category listed, and it doesn't obsolete or update anything. 💅

ABSTRACT 💖

ok so this paper gives a quick tour of the packet satellite tech that DARPA and a few other participating orgs in the U.K. and Norway developed 🌸 It also comes with a bibliography of relevant papers for researchers who want to dig into the experimental and operational experience with this dynamic satellite-sharing technique. main character research energy 🦋

INTRODUCTION 🧚

Packet satellite tech grew out of early packet switching work on multiaccess radio channels at the University of Hawaii, which was supported by DARPA. 🌈 The big difference between the earlier packet-switched ARPANET [1, 2] and the ALOHA system at Hawaii [3] was the idea of multiple transmitters dynamically sharing one common, directly-accessible radio channel 🔥

Now the ARPANET version: traffic sources put packets into the network through packet switches called Interface Message Processors (IMPs) 🍓 The IMPs used high speed point-to-point full-duplex telephone circuits [4] on a store-and-forward basis. All packet traffic for a given telephone circuit got queued in the IMP if needed, then sent as soon as the packet hit the front of the line. On full duplex circuits there's exactly one transmitter and one receiver in each direction. very structured, very neat 💅

ALOHA was a totally different vibe 🫶 It assigned a common transmit channel frequency to ALL radio terminals! A computer at the University of Hawaii received packet bursts from the remote terminals sharing that "multi-access" channel. Each terminal, run by a small processor, transmitted whenever it had traffic, then waited for an acknowledgement on a different frequency dedicated to the service host. If no ack came back, the terminal processor transmitted again at a randomly chosen time 🎲 The system assumed no store-and-forward or radio relay was needed. Later, the Hawaii researchers showed the ALOHA concept worked on a satellite channel linking Hawaii and Nasa-Ames through NASA's ATS-1 satellite [5, 6] 🛰️ A bunch of fancier satellite channel assignment strategies were also developed and analyzed in the early 1970's [7-13, 31] 🤓

THE ATLANTIC PACKET SATELLITE EXPERIMENT (SATNET) 🌍

In 1973, DARPA started developing a packet satellite system that would let many ground stations share one common, high speed channel 💜 The Atlantic Packet Satellite experiment used an INTELSAT-IV satellite and was carried out with the cooperation and support of the British Post Office, COMSAT Corporation, Linkabit Corporation, and Bolt Beranek and Newman Corporation. Later on, the Norwegian Telecommunication Administration and the Norwegian Defense Research Establishment (NDRE) joined in too 🇳🇴 Along with University College London and COMSAT Laboratories, NDRE became one of the major users of the SATNET system.

From 1975 to 1978, SATNET went through a broad range of performance evaluations and tests 📊 Since 1979 it's been a stable support for international experiments and demos of command and control tech that's of interest to DARPA, NDRE, and the U.K. Royal Signals and Radar Establishment (RSRE). Late in 1982, a ground station was added to connect the German Aeronautics and Space Research Establishment (DFVLR) 🇩🇪

The early development of SATNET is outlined in [14]. The system design is documented in [15-22]. Experience with operating SATNET is reported in [23-24], and experimental results are in [25-26]. Potential services that this tech might support are discussed in [27] 🦋

The integration of packet satellite tech into a larger, multiple packet network context is discussed in [28-29] 🧩 The system is expected to keep going to support joint research by DARPA, RSRE, NDRE, DFVLR, and UCL. DARPA and the U.S. Defense Communications Agency are experimenting with a 3 megabit/second domestic packet satellite system, to find out whether packetized voice and data services can be integrated economically with this tech 🎙️ And DARPA and the U.S. Naval Electronic Systems Command recently demoed a Mobile Access Terminal Network (MATNET). It uses packet satellite techniques to support ship-ship and ship-shore communication over a shared FLTSATCOM satellite channel [30] ⚓

ACKNOWLEDGEMENTS 🫶

Packet Satellite tech involved a lot of institutions and individuals, but special credit for making SATNET and its successor systems happen goes to Dr. Robert E. Kahn, Director, Information Processing Techniques Office, DARPA 👑 He gave continuous support and technical contributions throughout the development and maturation of this tech. iconic 🙌

REFERENCES 📚

1. L.G. Roberts and B.D. Wessler, "Computer Network Development to Achieve Resource Sharing," Spring Joint Computer Conference, AFIPS Proceedings, Vol. 36, 1970, pp. 543-549.
2. R.E. Kahn, "Resource Sharing Computer Networks," Proceedings of the IEEE, Vol. 60, No. 11, November 1972, pp. 1397-1407.
3. N. Abramson, "The Aloha System - Another Alternative for Computer Communications," AFIPS Conference Proceedings, Vol. 36, 1970, pp. 295-298.
4. F.E. Heart, et al, "The Interface Message Processor of the ARPA Computer Network, Spring Joint Computer Conference, AFIPS Proceedings, 1970, pp. 551-567.
5. R. Binder, et al, "Aloha Packet Broadcasting--a retrospect," AFIPS Conference Proceedings, National Computer Conference, 1975, pp. 203-215.
6. N. Abramson and F. Kuo, Editors, Computer Communication Networks, Prentice Hall, Englewood Cliffs, N.J., 1973.
7. L. Kleinrock and S. Lam, "Packet Switching in a Slotted Satellite Channel," AFIPS Conference Proceedings, NCC, 1973, pp. 703-710.
8. L. Kleinrock and F. Tobagi, "Random Access Techniques for Data Transmission over Packet Switched Radio Channels," AFIPS Conference Proceedings, NCC, 1975, pp. 187-201.
9. L. Kleinrock and S.S. Lam, "Packet Switching in a Multiaccess Broadcast Channel: Performance Evaluation," IEEE Transactions on Communication, Vol. COM-23, 1975, pp. 410-423.
10. L.G. Roberts, "Aloha Packet System with and without Slots and Capture," ACM SIGCOMM, Computer Communication Review, Vol 5, No. 2, April 1975.
11. S.S. Lam and L. Kleinrock, "Packet Switching in a Multi-access Broadcast Channel: Dynamic Control Procedures," IEEE Transactions on Communication, Vol Com-23, September, 1975.
12. L.G. Roberts, "Dynamic Allocation of Satellite Capacity through Packet Reservation," AFIPS Conference Proceedings, NCC, 1973, pp. 711-716.
13. N. Abramson, "Packet Switching with Satellites," AFIPS Conference Proceedings, NCC, 1973, pp. 695-702.
14. R.E. Kahn, "The Introduction of Packet Satellite Communications," National Telecommunications Conference, Nov. 1979, p. 45.1.1-45.1.8.
15. I.M. Jacobs, et al, "CPODA - A Demand Assignment Protocol for SATNET," Fifth Data Communications Symposium, Snowbird, Utah, 1977.
16. I.M. Jacobs, et.al, "General Purpose Satellite Networks," Proceedings IEEE, Vol 66, No. 11, November 1978, pp. 1448-1467.
17. I.M. Jacobs, et al, "Packet Satellite Network Design Issues," Proceedings, NTC, November 1979.
18. L. Palmer, J. Kaiser, S. Rothschild and D. Mills, "SATNET Packet Data Transmission," COMSAT Technical Review, Volume 12, No. 1, Spring 1982, pp. 181-212.
19. Weissler, et al, "Synchronization and Multiple Access Protocol in the Initial Satellite IMP," COMPCON, September 1978.
20. Hsu and Lee, "Channel Scheduling Snychronization for the PODA Protocol," ICC, June 1978.
21. E. Killian and R. Binder, "Control Issues in a PODA Voice/Data Satellite Network," ICC, June 1980.
22. C. Heegaard, J. Heller and A. Viterbi, "A Microprocessor-based PSK Modem for Packet Transmission over Satellite Channels," IEEE Transactions on Communications, COM-26, No. 5, May 1978, pp. 552-564.
23. P. Cudhea, D. McNeill, D. Mills, "SATNET Operations," AIAA 9th Communications Satellite Systems Conference, Collection of Technical Papers, 1982, pp. 100-105.
24. D.A. McNeill, et al, "SATNET Monitoring and Control," Proceedings of the NTC, November 1979.
25. P.T. Kirstein, et al, "SATNET Applications Activities," Proceedings of the NTC, November 1979.
26. W.W. Chu, et al, "Experimental Results on the Packet Satellite Network," Proceedings of the NTC, November 1979.
27. E.V. Hoversten and H. L. Van Trees, "International Broadcast Packet Satellite Services," ICCC Conference Proceedings, Kyoto, Japan, September 1978.
28. V.G. Cerf and R.E. Kahn, "A Protocol for Packet Network Intercommunication," IEEE Trans. on Comm., Vol. COM-23, May 1974, pp. 637-648.
29. V.G. Cerf and P.T. Kirstein, "Issues in Packet Network Interconnection," IEEE Proceedings, Vol. 66, No. 11, Nov 1978, pp. 1386-1408.
30. L. Evenchik, D. McNeill, R.P. Rice, F. Deckelman, et al, "MATNET, an Experimental Navy Shipboard Satellite Communications Network, " IEEE INFOCOM 82 Proceedings, March, 1982.
31. M.L. Molle and L. Kleinrock, "Analysis of Concentrated ALOHA Satellite Links," Sixth Data Communications Symposium, Nov 27-29, 1979, pp. 87-95.