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network working group b. rajagopalanrequest for comments: 3251 tellium, inc.category: informational 1 april 2002electricity over ipstatus of this memothis memo provides information for the internet community. it doesnot specify an internet standard of any kind. distribution of thismemo is unlimited.copyright noticecopyright (c) the internet society (2002). all rights reserved.abstractmostly pointless lamp switching (mplamps) is an architecture forcarrying electricity over ip (with an mpls control plane). accordingto our marketing department, mplamps has the potential todramatically lower the price, ease the distribution and usage, andimprove the manageability of delivering electricity. this documentis motivated by such work as sonet/sdh over ip/mpls (with apologiesto the authors). readers of the previous work have been observedscratching their heads and muttering, "what next?". this documentanswers that question.this document has also been written as a public service. the "sub-ip" area has been formed to give equal opportunity to those workingon technologies outside of traditional ip networking to writecomplicated ietf documents. there are possibly many who arewondering how to exploit this opportunity and attain high visibility.towards this goal, we see the topics of "foo-over-mpls" (or mplscontrol for random technologies) as highly amenable for producing acountless number of unimplementable documents. this documentillustrates the key ingredients that go into producing any "foo-over-mpls" document and may be used as a template for all such work.1. conventions used in this documentthe key words "must", "must not", "do", "don't", "required", "shall","shall not", "should", "should not", "recommended", "may", "may be"and "optional" in this document do not mean anything.rajagopalan informational [page 1]rfc 3251 electricity over ip 1 april 20022. pre-requisite for reading this documentwhile reading this document, at various points the readers may havethe urge to ask questions like, "does this make sense?", "is thisfeasible?," and "is the author sane?". the readers must have theability to suppress such questions and read on. other than this, nospecific technical background is required to read this document. incertain cases (present document included), it may be required thatreaders have no specific technical background.3. introductionit was recently brought to our attention that the distributionnetwork for electricity is not an ip network! after absorbing theshock that was delivered by this news, the following thoughtsoccurred to us:1. electricity distribution must be based on some outdated technology(called "legacy distribution system" or lds in the rest of thedocument).2. an lds not based on the internet technology means that twodifferent networks (electricity and ip) must be administered andmanaged. this leads to inefficiencies, higher cost andbureaucratic foul-ups (which possibly lead to blackouts incalifornia. we are in the process of verifying this usingsimulations as part of a student's ms thesis).3. the above means that a single network technology (i.e., ip) mustbe used to carry both electricity and internet traffic.4. an internet draft must be written to start work in this area,before someone else does.5. such a draft can be used to generate further drafts, ensuring thatwe (and ccamp, mpls or another responsible working group) will bebusy for another year.6. the draft can also be posted in the "white papers" section of ourcompany web page, proclaiming us as revolutionary pioneers.hence the present document.4. terminologymplamps: mostly pointless lamp switching - the architectureintroduced in this document.lamp: an end-system in the mplamps architecture (clashes with theietf notion of end-system but of course, we don't care).ler: low-voltage electricity receptor - fancy name for "lamp".rajagopalan informational [page 2]rfc 3251 electricity over ip 1 april 2002es: electricity source - a generator.lsr: load-switching router - an mplamps device used in the coreelectricity distribution network.lds: legacy distribution system - an inferior electricitydistribution technology that mplamps intends to replace.rsvp: rather screwed-up, but router vendors push it - an ip signalingprotocol.rsvp-te: rsvp with tariff extensions - rsvp adaptation for mplamps,to be used in the new deregulated utilities environment.crldp: for crying out loud, don't do rsvp - another ip signalingprotocol.ospf: often seizes-up in multiple area configurations - ahierarchical ip routing protocol.isis: it's not ospf, yet it somehow survives - another routingprotocol.ospf-te, isis-te: ospf and isis with tariff extensions.cops: policemen. folks who scour all places for possibilities toslip in the common open policy service protocol.vpn: voltage protected network - allows a customer with multiplesites to receive electricity with negligible voltage fluctuation dueto interference from other customers.sub-ip: substitute ip everywhere - an effort in the ietf to getinvolved in technical areas outside of traditional ip networking(such as mplamps).itu: international tariffed utilities association - a utilities tradegroup whose work is often ignored by the ietf.5. backgroundwe dug into the electricity distribution technology area to get somebackground. what we found stunned us, say, with the potency of abare 230v a/c lead dropped into our bathtub while we were still init. to put it simply, electricity is generated and distributed alonga vast lds which does not have a single router in it (lsr orotherwise)! furthermore, the control of devices in this network ismostly manual, done by folks driving around in trucks. afterrajagopalan informational [page 3]rfc 3251 electricity over ip 1 april 2002wondering momentarily about how such a network can exist in the 21stcentury, we took a pencil and paper and sketched out a scenario forintegrating the lds network with the proven internet technology. thefundamental points we came up with are:1. ip packets carry electricity in discrete, digitized form.2. each packet would deliver electricity to its destination (e.g., adevice with an ip address) on-demand.3. mpls control will be used to switch packets within the core lds,and in the edge premises. the architecture for this is referredto as mostly-pointless lamp switching (mplamps).4. the mplamps architectural model will accommodate both the overlaymodel, where the electricity consuming devices (referred to as"lamps") are operated over a distinct control plane, and the peermodel, in which the lamps and the distribution network use asingle control plane.5. rsvp-te (rsvp with tariff extensions) will be used forestablishing paths for electricity flow in a de-regulatedenvironment.6. cops will be used to support accounting and policy.after jotting these points down, we felt better. we then noted thefollowing immediate advantages of the proposed scheme:1. switches and transformers in the lds can be replaced by lsrs,thereby opening up a new market for routers.2. electricity can be routed over the internet to reach remote placeswhich presently do not have electricity connections but have onlyinternet kiosks (e.g., rural india).3. electrical technicians can be replaced by highly paid ip networkadministrators, and4. the ietf can get involved in another unrelated technology area.in the following, we describe the technical issues in a vague manner.6. electricity encodingthe discrete voltage encoding (dve) scheme has been specified in itustandard g.110/230v [2] to digitize electrical voltages. in essence,an electricity source (es) such as a generator is connected to a dvencoder that encodes the voltage and current, and produces a bitstream. this bit stream can be carried in ip packets to variousdestinations (referred to as lers - low-voltage electricityreceptors) on-demand. at the destination, a dv decoder produces theright voltage and current based on the received bit stream. it is tobe determined whether the real-time transport protocol (rtp) can berajagopalan informational [page 4]rfc 3251 electricity over ip 1 april 2002used for achieving synchronization and end-to-end control. we leavedraft writing opportunities in the rtp area to our friends andcolleagues.7. mplamps architecture7.1 overviewin an lds, the long-haul transmission of electricity is at highvoltages. the voltage is stepped down progressively as electricityflows into local distribution networks and is finally delivered tolers at a standard voltage (e.g., 110v). thus, the lds is ahierarchical network. this immediately opens up the possibility ofospf and isis extensions for routing electricity in a transmissionnetwork, but we'll contain the urge to delve into these productiveinternet draft areas until later. for the present, we limit ourdiscussion merely to controlling the flow of electricity in an ip-based distribution network using mplamps.under mplamps, a voltage is equated to a label. in the distributionnetwork, each switching element and transformer is viewed as a load-switching router (lsr). each ip packet carrying an electricity flowis assigned a label corresponding to the voltage. electricitydistribution can then be trivially reduced to the task of label(voltage) switching as electricity flows through the distributionnetwork. the configuration of switching elements in the distributionnetwork is done through rsvp-te to provide electricity on demand.we admit that the above description is vague and sounds crazy. theexample below tries to add more (useless) details, without removingany doubts the reader might have about the feasibility of thisproposal:example: turning on a lampit is assumed that the lamp is controlled by an intelligent device(e.g, a (light) switch with an mplamps control plane). turning thelamp on causes the switch to issue an rsvp-te request (a path messagewith new objects) for the electricity flow. this path messagetraverses across the network to the es. the resv message issued inreturn sets up the label mappings in lsrs. finally, electricitystarts flowing along the path established. it is expected that theentire process will be completed within a few seconds, thereby givingthe mplamps architecture a distinct advantage over lighting a candlewith a damp match stick.rajagopalan informational [page 5]rfc 3251 electricity over ip 1 april 20027.2 overlay vs peer modelsas noted before, there are two control plane models to be considered.under the overlay model, the lamps and the distribution networkutilize distinct control planes. under the peer model, a singlecontrol plane is used. a number of arguments can be made for onemodel versus the other, and these will be covered in the upcomingframework document. we merely observe here that it is the lampvendors who prefer the peer model against the better judgement of thelsr vendors. we, however, want to please both camps regardless ofthe usefulness of either model. we therefore note here that mplampssupports both models and also migration scenarios from overlay topeer.7.3 routing in the core networkthe above description of the hierarchical distribution systemimmediately opens up the possibility of applying ospf and isis withsuitable extensions. the readers may rest assured that we arealready working on such concepts as voltage bundling, multi-areatariff extensions, insulated lsas, etc. future documents willdescribe the details.7.4 voltage protected networks (vpns)vpns allow a customer with multiple sites to get guaranteedelectricity supply with negligible voltage fluctuations due tointerference from other customers. indeed, some may argue that theentire mplamps architecture may be trashed if not for the possibilityof doing vpns. whatever be the case, vpns are a hot topic today andthe readers are forewarned that we have every intention of writingseveral documents on this. specifically, bgp-support for vpns is anarea we're presently eyeing with interest.8. multicastit has been observed that there is a strong spatial and temporallocality in electricity demand. itu study group 55 has studied thisphenomenon for over a decade and has issued a preliminary report.this report states that when a lamp is turned on in one house, it isusually the case that lamps are turned on in neighboring houses ataround the same time (usually at dusk) [3]. this observation has aserious implication on the scalability of the signaling mechanism.specifically, the distribution network must be able to handle tens ofthousands of requests all at once. the signaling load can be reducedif multicast delivery is used. briefly, a request for electricity isnot sent from the lamp all the way to an es, but is handled by thefirst lsr that is already in the path to another lamp.rajagopalan informational [page 6]rfc 3251 electricity over ip 1 april 2002support for this requires the application of multicast routingprotocols together with rsvp-te shared reservation styles and thedevelopment of mplamps multicast forwarding mode. we are currentlystudying the following multicast routing protocol:o dvmrp: discrete voltage multicast routing protocol - this protocolworks over existing voltage routing protocols but the danger here isthat electricity is delivered to all lamps when any one lamp isturned on. indeed, the switching semantics gets annoying - all lampsget turned on periodically and those not needed must be switched offeach time manually.other protocols we will eventually consider are current-based tree(cbt) and practically irrelevant multicast (pim). an issue we aregreatly interested in is multicast scope: we would like support fordistributing electricity with varying scope, from lamps within asingle christmas tree to those in entire cities. needless to say, wewill write many detailed documents on these topics as timeprogresses.9. security considerationsthis document must be secured in a locked cabinet to prevent it frombeing disposed off with the trash.10. summarythis document described the motivation and high level concepts behindmostly pointless lamp switching (mplamps), an architecture forelectricity distribution over ip. mplamps utilizes dve (discretevoltage encoding), and an mpls control plane in the distributionnetwork. since the aim of this document is to be a high-visibilityplace-holder, we did not get into many details of mplamps. numerousfuture documents, unfortunately, will attempt to provide thesedetails.11. references1. a. malis, et al., "sonet/sdh circuit emulation service over mpls(cem) encapsulation", internet draft, work in progress.2. international tarriffed utilities association draft standard, itug.110/230v, "discrete voltage encoding", march, 1999.3. international tarriffed utilities association technical report,itu (sg-55) tr-432-2000, "empirical models for energyutilization", september, 2000.rajagopalan informational [page 7]rfc 3251 electricity over ip 1 april 200212. disclaimerthe opinions expressed in this document are solely the author's.company's opinions, as always, are proprietary and confidential andmay be obtained under appropriate ndas.13. author's addressbala rajagopalantellium, inc.2 crescent placeocean port, nj 07757phone: 732-923-4237email: braja@tellium.comrajagopalan informational [page 8]rfc 3251 electricity over ip 1 april 200214. full copyright statementcopyright (c) the internet society (2002). all rights reserved.this document and translations of it may be copied and furnished toothers, and derivative works that comment on or otherwise explain itor assist in its implementation may be prepared, copied, publishedand distributed, in whole or in part, without restriction of anykind, provided that the above copyright notice and this paragraph areincluded on all such copies and derivative works. however, thisdocument itself may not be modified in any way, such as by removingthe copyright notice or references to the internet society or otherinternet organizations, except as needed for the purpose ofdeveloping internet standards in which case the procedures forcopyrights defined in the internet standards process must befollowed, or as required to translate it into languages other thanenglish.the limited permissions granted above are perpetual and will not berevoked by the internet society or its successors or assigns.this document and the information contained herein is provided on an"as is" basis and the internet society and the internet engineeringtask force disclaims all warranties, express or implied, includingbut not limited to any warranty that the use of the informationherein will not infringe any rights or any implied warranties ofmerchantability or fitness for a particular purpose.acknowledgementfunding for the rfc editor function is currently provided by theinternet society.rajagopalan informational [page 9]
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