Movatterモバイル変換

Network Working Group                                     B. RajagopalanRequest for Comments: 3251                                 Tellium, Inc.Category: Informational                                     1 April 2002Electricity over IPStatus of this Memo   This memo provides information for the Internet community.  It does   not specify an Internet standard of any kind.  Distribution of this   memo is unlimited.Copyright Notice   Copyright (C) The Internet Society (2002).  All Rights Reserved.Abstract   Mostly Pointless Lamp Switching (MPLampS) is an architecture for   carrying electricity over IP (with an MPLS control plane).  According   to our marketing department, MPLampS has the potential to   dramatically lower the price, ease the distribution and usage, and   improve the manageability of delivering electricity.  This document   is motivated by such work as SONET/SDH over IP/MPLS (with apologies   to the authors).  Readers of the previous work have been observed   scratching their heads and muttering, "What next?".  This document   answers 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 working   on technologies outside of traditional IP networking to write   complicated IETF documents.  There are possibly many who are   wondering how to exploit this opportunity and attain high visibility.   Towards this goal, we see the topics of "foo-over-MPLS" (or MPLS   control for random technologies) as highly amenable for producing a   countless number of unimplementable documents.  This document   illustrates 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 document   The 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 document   While reading this document, at various points the readers may have   the urge to ask questions like, "does this make sense?", "is this   feasible?," and "is the author sane?".  The readers must have the   ability to suppress such questions and read on.  Other than this, no   specific technical background is required to read this document.  In   certain cases (present document included), it may be REQUIRED that   readers have no specific technical background.3. Introduction   It was recently brought to our attention that the distribution   network for electricity is not an IP network!  After absorbing the   shock that was delivered by this news, the following thoughts   occurred to us:   1. Electricity distribution must be based on some outdated technology      (called "Legacy Distribution System" or LDS in the rest of the      document).   2. An LDS not based on the Internet technology means that two      different networks (electricity and IP) must be administered and      managed.  This leads to inefficiencies, higher cost and      bureaucratic foul-ups (which possibly lead to blackouts in      California.  We are in the process of verifying this using      simulations as part of a student's MS thesis).   3. The above means that a single network technology (i.e., IP) must      be 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 that      we (and CCAMP, MPLS or another responsible working group) will be      busy for another year.   6. The draft can also be posted in the "white papers" section of our      company web page, proclaiming us as revolutionary pioneers.   Hence the present document.4. Terminology   MPLampS: Mostly Pointless Lamp Switching - the architecture   introduced in this document.   Lamp: An end-system in the MPLampS architecture (clashes with the   IETF 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 2002   ES: Electricity source - a generator.   LSR: Load-Switching Router - an MPLampS device used in the core   electricity distribution network.   LDS: Legacy Distribution System - an inferior electricity   distribution technology that MPLampS intends to replace.   RSVP: Rather Screwed-up, but router Vendors Push it - an IP signaling   protocol.   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 signaling   protocol.   OSPF: Often Seizes-up in multiPle area conFigurations - a   hierarchical IP routing protocol.   ISIS: It's not oSpf, yet It somehow Survives - another routing   protocol.   OSPF-TE, ISIS-TE: OSPF and ISIS with Tariff Extensions.   COPS: Policemen.  Folks who scour all places for possibilities to   slip in the Common Open Policy Service protocol.   VPN: Voltage Protected Network - allows a customer with multiple   sites to receive electricity with negligible voltage fluctuation due   to interference from other customers.   SUB-IP: SUBstitute IP everywhere - an effort in the IETF to get   involved in technical areas outside of traditional IP networking   (such as MPLampS).   ITU: International Tariffed Utilities association - a utilities trade   group whose work is often ignored by the IETF.5. Background   We dug into the electricity distribution technology area to get some   background.  What we found stunned us, say, with the potency of a   bare 230V A/C lead dropped into our bathtub while we were still in   it.  To put it simply, electricity is generated and distributed along   a vast LDS which does not have a single router in it (LSR or   otherwise)!  Furthermore, the control of devices in this network is   mostly manual, done by folks driving around in trucks.  AfterRajagopalan                  Informational                      [Page 3]

RFC 3251                  Electricity over IP               1 April 2002   wondering momentarily about how such a network can exist in the 21st   century, we took a pencil and paper and sketched out a scenario for   integrating the LDS network with the proven Internet technology.  The   fundamental 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., a      device 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 referred      to as Mostly-Pointless Lamp Switching (MPLampS).   4. The MPLampS architectural model will accommodate both the overlay      model, where the electricity consuming devices (referred to as      "lamps") are operated over a distinct control plane, and the peer      model, in which the lamps and the distribution network use a      single control plane.   5. RSVP-TE (RSVP with Tariff Extensions) will be used for      establishing paths for electricity flow in a de-regulated      environment.   6. COPS will be used to support accounting and policy.   After jotting these points down, we felt better.  We then noted the   following 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 places      which presently do not have electricity connections but have only      Internet kiosks (e.g., rural India).   3. Electrical technicians can be replaced by highly paid IP network      administrators, and   4. The IETF can get involved in another unrelated technology area.   In the following, we describe the technical issues in a vague manner.6. Electricity Encoding   The Discrete Voltage Encoding (DVE) scheme has been specified in ITU   standard G.110/230V [2] to digitize electrical voltages.  In essence,   an Electricity Source (ES) such as a generator is connected to a DV   encoder that encodes the voltage and current, and  produces a bit   stream.  This bit stream can be carried in IP packets to various   destinations (referred to as LERs - Low-voltage Electricity   Receptors) on-demand.  At the destination, a DV decoder produces the   right voltage and current based on the received bit stream.  It is to   be determined whether the Real-time Transport Protocol (RTP) can beRajagopalan                  Informational                      [Page 4]

RFC 3251                  Electricity over IP               1 April 2002   used for achieving synchronization and end-to-end control.  We leave   draft writing opportunities in the RTP area to our friends and   colleagues.7. MPLampS Architecture7.1  Overview   In an LDS, the long-haul transmission of electricity is at high   voltages.  The voltage is stepped down progressively as electricity   flows into local distribution networks and is finally delivered to   LERs at a standard voltage (e.g., 110V).  Thus, the LDS is a   hierarchical network.  This immediately opens up the possibility of   OSPF and ISIS extensions for routing electricity in a transmission   network, but we'll contain the urge to delve into these productive   internet draft areas until later.  For the present, we limit our   discussion 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 distribution   network, each switching element and transformer is viewed as a load-   switching router (LSR).  Each IP packet carrying an electricity flow   is assigned a label corresponding to the voltage.  Electricity   distribution can then be trivially reduced to the task of label   (voltage) switching as electricity flows through the distribution   network.  The configuration of switching elements in the distribution   network is done through RSVP-TE to provide electricity on demand.   We admit that the above description is vague and sounds crazy.  The   example below tries to add more (useless) details, without removing   any doubts the reader might have about the feasibility of this   proposal:   Example: Turning on a Lamp   It is assumed that the lamp is controlled by an intelligent device   (e.g, a (light) switch with an MPLampS control plane).  Turning the   lamp on causes the switch to issue an RSVP-TE request (a PATH message   with new objects) for the electricity flow.  This PATH message   traverses across the network to the ES.  The RESV message issued in   return sets up the label mappings in LSRs.  Finally, electricity   starts flowing along the path established.  It is expected that the   entire process will be completed within a few seconds, thereby giving   the MPLampS architecture a distinct advantage over lighting a candle   with a damp match stick.Rajagopalan                  Informational                      [Page 5]

RFC 3251                  Electricity over IP               1 April 20027.2  Overlay vs Peer Models   As noted before, there are two control plane models to be considered.   Under the overlay model, the lamps and the distribution network   utilize distinct control planes.  Under the peer model, a single   control plane is used.  A number of arguments can be made for one   model versus the other, and these will be covered in the upcoming   framework document.  We merely observe here that it is the lamp   vendors who prefer the peer model against the better judgement of the   LSR vendors.  We, however, want to please both camps regardless of   the usefulness of either model.  We therefore note here that MPLampS   supports both models and also migration scenarios from overlay to   peer.7.3 Routing in the Core Network   The above description of the hierarchical distribution system   immediately opens up the possibility of applying OSPF and ISIS with   suitable extensions.  The readers may rest assured that we are   already working on such concepts as voltage bundling, multi-area   tariff extensions, insulated LSAs, etc.  Future documents will   describe the details.7.4 Voltage Protected Networks (VPNs)   VPNs allow a customer with multiple sites to get guaranteed   electricity supply with negligible voltage fluctuations due to   interference from other customers.  Indeed, some may argue that the   entire MPLampS architecture may be trashed if not for the possibility   of doing VPNs.  Whatever be the case, VPNs are a hot topic today and   the readers are forewarned that we have every intention of writing   several documents on this.  Specifically, BGP-support for VPNs is an   area we're presently eyeing with interest.8. Multicast   It has been observed that there is a strong spatial and temporal   locality in electricity demand.  ITU Study Group 55 has studied this   phenomenon for over a decade and has issued a preliminary report.   This report states that when a lamp is turned on in one house, it is   usually the case that lamps are turned on in neighboring houses at   around the same time (usually at dusk) [3].  This observation has a   serious implication on the scalability of the signaling mechanism.   Specifically, the distribution network must be able to handle tens of   thousands of requests all at once.  The signaling load can be reduced   if multicast delivery is used.  Briefly, a request for electricity is   not sent from the lamp all the way to an ES, but is handled by the   first LSR that is already in the path to another lamp.Rajagopalan                  Informational                      [Page 6]

RFC 3251                  Electricity over IP               1 April 2002   Support for this requires the application of multicast routing   protocols together with RSVP-TE shared reservation styles and the   development of MPLampS multicast forwarding mode.  We are currently   studying the following multicast routing protocol:   o DVMRP: Discrete Voltage Multicast Routing Protocol - this protocol   works over existing voltage routing protocols but the danger here is   that electricity is delivered to all lamps when any one lamp is   turned on.  Indeed, the switching semantics gets annoying - all lamps   get turned on periodically and those not needed must be switched off   each time manually.   Other protocols we will eventually consider are Current-Based Tree   (CBT) and Practically Irrelevant Multicast (PIM).  An issue we are   greatly interested in is multicast scope: we would like support for   distributing electricity with varying scope, from lamps within a   single Christmas tree to those in entire cities.  Needless to say, we   will write many detailed documents on these topics as time   progresses.9. Security Considerations   This document MUST be secured in a locked cabinet to prevent it from   being disposed off with the trash.10. Summary   This document described the motivation and high level concepts behind   Mostly Pointless Lamp Switching (MPLampS), an architecture for   electricity distribution over IP.  MPLampS utilizes DVE (discrete   voltage encoding), and an MPLS control plane in the distribution   network.  Since the aim of this document is to be a high-visibility   place-holder, we did not get into many details of MPLampS.  Numerous   future documents, unfortunately, will attempt to provide these   details.11. References   1. 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, ITU      G.110/230V, "Discrete Voltage Encoding", March, 1999.   3. International Tarriffed Utilities association technical report,      ITU (SG-55) TR-432-2000, "Empirical Models for Energy      Utilization", September, 2000.Rajagopalan                  Informational                      [Page 7]

RFC 3251                  Electricity over IP               1 April 200212. Disclaimer   The opinions expressed in this document are solely the author's.   Company's opinions, as always, are proprietary and confidential and   may be obtained under appropriate NDAs.13. Author's Address   Bala Rajagopalan   Tellium, Inc.   2 Crescent Place   Ocean Port, NJ 07757   Phone: 732-923-4237   EMail: braja@tellium.comRajagopalan                  Informational                      [Page 8]

RFC 3251                  Electricity over IP               1 April 200214. Full Copyright Statement   Copyright (C) The Internet Society (2002).  All Rights Reserved.   This document and translations of it may be copied and furnished to   others, and derivative works that comment on or otherwise explain it   or assist in its implementation may be prepared, copied, published   and distributed, in whole or in part, without restriction of any   kind, provided that the above copyright notice and this paragraph are   included on all such copies and derivative works.  However, this   document itself may not be modified in any way, such as by removing   the copyright notice or references to the Internet Society or other   Internet organizations, except as needed for the purpose of   developing Internet standards in which case the procedures for   copyrights defined in the Internet Standards process must be   followed, or as required to translate it into languages other than   English.   The limited permissions granted above are perpetual and will not be   revoked 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 ENGINEERING   TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING   BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION   HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.Acknowledgement   Funding for the RFC Editor function is currently provided by the   Internet Society.Rajagopalan                  Informational                      [Page 9]