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Network Working Group                                     Poorer RichardRequest for Comments: 1216                             Almanac Institute                                                           Prof. Kynikos                                                   Miskatonic University                                                            1 April 1991Gigabit Network Economics and Paradigm ShiftsStatus of this Memo   This memo proposes a new standard paradigm for the Internet   Activities Board (IAB) standardization track.  Distribution of this   memo is unlimited.1. Introduction   The history of computer communication contains many examples of   efforts to align the capabilities of processors to that of   communication media.  Packet switching is the classic case of a   careful tradeoff between the costs of memory, processing, and   communications bandwidth.   With all of the attention and publicity focused on gigabit networks,   not much notice has been given to small and largely unfunded research   efforts which are studying innovative approaches for dealing with   technical issues within the constraints of economic science.  This   memo defines one such paradigm.2. Contemporary Network Economics   Recent cost estimates predict a continuing decline in the cost for   processing, memory, and communication.  One recent projection put the   decline for $/bit and $/MIP at 99% per decade and put the decline for   $/bps at 90% per decade.  Scalable parallel processor designs may   accelerate the cost declines for CPU and memory, but no similar   accelerated decline should be expected in the cost of communications.   Such a decline would imply eventual declines in the cost of 56Kbps   service used for voice, resulting in a negative rate of return for   telecommunications carriers, an unlikely eventuality even if free-   market forces are carried to their logical extreme.   Increases in processing power create additional demand for   communications bandwidth, but do nothing to pay for it.  While we   will sell no paradigm before its time, the 9% difference,   particularly after compounding is taken into account, will bankrupt   the internet community unless a paradigm shift takes place.Richard & Kynikos                                               [Page 1]

RFC 1216     Gigabit Network Economics and Paradigm Shifts    April 19913. The ULS Paradigm Shift   The ULS paradigm shift breaks the downward spiral by concentrating on   end-to-end datagrams and virtual circuit services operating in the   .01 uGbps region, namely Ultra Low Speed networking.   However,   "The worlds best technological paradigm shifts are useless unless   they (a) are economically viable, (b) have clear applicability, (c)   are technically feasible."           --Milton John in "Paradigms Lost"3.1 Economic Viability   Cost projections indicate that individual ULS circuits can be   provided at a cost of <$.03/month due to the unusually high   multiplexing that will be possible on Gbit links.  The 10 THz   bandwidth of existing optical fibers will be able to support on the   order of 1 TUser, handling population growth, and even internet   growth, for some time.  Moreover, if $.03/month is a significant   barrier to entry, substantial discounts appear to be economically   feasible.3.2 Clear Applicability   A fundamental principle of networking is that network speed must   match the application.  We have identified a number of critical   applications that are matched to ULS technology.  Below we itemize a   few of these, but we provide a brief description for only the first;   the match for the others should be equally obvious.   - Low priority facsimile: A large percentage of documents and letters     are sent via facsimile not because they need sub-minute delivery,     but because they carry signatures or graphics.  In these cases, a     three-hour delivery (comparable to the value reliably achieved on     many of today's packet-based email systems) is sufficient.  With     proper compression, this delivery time can be achieved over a     ULSnet.   - Real time data (e.g., tracking glaciers)   - US postal service   - Contracting for research   To be truly viable, ULS networking must scale, and indeed it does.Richard & Kynikos                                               [Page 2]

RFC 1216     Gigabit Network Economics and Paradigm Shifts    April 1991   With some effort, we envision extending the technology to the   extremely-low-speed regime.  Applications that scale from the ULS   applications above are:   - Real time data (e.g., gravity wave detectors)   - Italian postal service   - Congressional budget process3.3 Technical Feasibility   The hardware issues are well in hand.  The remaining issues are   protocol related.  To examine them, we must extrapolate backward from   some well known networking principles.   "Gigabit networks require new protocols."   The clear inference here is that ULS will require old protocols, so   as we recede into the future, we should expect the following:   ULS will require minimal development.  Although we may need research   in storage technology to recover the software from old media such as   decayed magnetic dump tapes, paper tape, and partially recycled card   decks, this effort will be more than offset by the savings.   ULS protocols will be well documented, amenable to verification, and   suitable for MSI implementation in Silicon, or even Germanium or   relays.  In particular, the alternating bit protocol [1] is a leading   contender.   "Bad news travel fast."   Therefore, ULS gives preferential treatment to good news.  While this   will delay the delivery of bills, notices from timeshare   condominiums, and contest announcements, it will also produce   immediate productivity gains on several mailing lists.3.4 Problems Requiring Work   ULS is not without problems.   Some other well-known protocol suites are well ahead of ULS in   exploring the desired performance operating point.  We note our   concern about the dearth of domestic (U.S.-based) research and   development in this important area.  This is particularly disturbing   in light of the level of work now underway in other countries.   Efficiency is a problem:Richard & Kynikos                                               [Page 3]

RFC 1216     Gigabit Network Economics and Paradigm Shifts    April 1991   - All ULS protocols incorporate slow-start.   - Lower data rates mean fewer errors.   - Whereas modern protocols use 32 bit sequence numbers,     acknowledgment fields, etc., ULS headers can be quite small (1 bit     sequence numbers for the alternating-bit protocol).  Thus the     header/data ratio shrinks.   The net result is "creeping efficiency" which tends to push us away   from the proper ULS operating point.  While we have no definitive   solution, there are several promising palliatives:   - Forward Error Insertion (FEI)   - Negative window scaling factors   - New protocol layers   - Multiple presentation layers4. Conclusions   The road to Ultra Low Speed (ULS) technology is long, slow, and easy.REFERENCES and BIBLIOGRAPHY   [1] Lynch, W. "Reliable full-duplex file transmission over half-       duplex telephone lines", CACM, pp. 407-410, June 1968.Security Considerations       Security issues are not discussed in this memo.Authors' Addresses       Dr. Poorer Richard       Almanac Institute       Center against Misoneoism       Campo Imperatore, Italy       EMail:  none       Prof. Kynikos       Miskatonic University       Arkham, MA.       Email: Kynikos@Cthulu.Miskatonic.EDURichard & Kynikos                                               [Page 4]