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Networking Power Science Technology

New Computer Powered By PoE 354

BlakeCaldwell writes "BBC News is reporting about a new PC that's powered via a network cable rather than through a wall socket. The computer only requires 12 watts, lower than the upper limit of 15.4 watts that power over ethernet (PoE) can supply. FTA: 'PoE could end up being a universal power supply system as the cables and connectors for it are the same all over the world. By contrast power sockets and plugs differ by country.'"
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New Computer Powered By PoE

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  • Almost Brilliant (Score:4, Insightful)

    by AKAImBatman ( 238306 ) * <{akaimbatman} {at} {gmail.com}> on Friday April 29, 2005 @10:19AM (#12383076) Homepage Journal
    I was thinking that this had to be one of the most brilliant ideas ever, right up until I realized that users are moving toward WIFI for connectivity. If this had srrived two to three years ago, we might all be using it now. But at this juncture? Likely to be ignored. :-/
    • Well, power over WiFi never really took off with people discovering that mother nature had blessed them with an internal receiver.
    • by terraformer ( 617565 ) <tpb@pervici.com> on Friday April 29, 2005 @10:28AM (#12383201) Journal
      I agree totally, but with one caveat. I work in energy efficiency and specifically that of computers. Business and Enterprise continue to use 10baseT and show no signs of changing that for their desktops (not saying they are not using WiFi...) and a business with 10K pcs spends hundreds of thousands to as much as a million dollars on energy a year for PCs (including monitor). What this eliminates is a power supply per pc and the attendant overhead. Consolidating the power supplies groups of computers (power supplies/transformers have efficiency issues depending on load). Also, this forces them to build a desktop with the usage profile of a highly efficient laptop to get under the 15.4 watt limit. The cost savings of using this technology could be very attractive to business. The WiFi concern is one in home and small business networks primarily.
      • I work for a public university. The people who are accountable for the equipment budget and the people who pay the light bill never talk.

        I recommend flat panel monitors to people based on aesthetics and reliability. Power consumption (30-40 watts for an LCD, 150 for a CRT) is a non-issue with users, since the power bill is paid by a central campus entity and doesn't show up on our departmental budgets at all.

        Actually, I don't know who pays the power bill. Maybe nobody!
        • Re:Almost Brilliant (Score:5, Interesting)

          by mrm677 ( 456727 ) on Friday April 29, 2005 @10:44AM (#12383392)
          I work for a public university. The people who are accountable for the equipment budget and the people who pay the light bill never talk.

          As a student, I worked at several of the computer labs at a large university (40,000 students). One late night when I was closing down, I thought to myself how silly it was to keep the CRT monitors powered on. This was before things automatically shut-off. So I went around to about 200 computers and shut-off the monitors. The next day I got in trouble by my manager...they didn't like my idea at all and didn't care about the heat or electricity savings. Apparently going around to turn them back on in the morning was too much work! I figure for about 6 years (before the advent of auto-shutoff CRTs and LCDs), this university ran > 1000 CRTs 24/7. Anybody care to guestimate how much electricity they could have saved over this time period?

          • Re:Almost Brilliant (Score:5, Informative)

            by RealProgrammer ( 723725 ) on Friday April 29, 2005 @11:02AM (#12383607) Homepage Journal
            this university ran > 1000 CRTs 24/7. Anybody care to guestimate how much electricity they could have saved over this time period?

            (Using conservative figures)
            At 100 watts, a monitor consumes 1200 watts in 12 hours or (at 7 cents per kWh) about $.084 in electricity every night. Call it $25/year.

            1000 monitors waste $25,000/year.

            Depending on your climate, heat dissipation is really hard to figure, since in the winter all those monitors made the buildings easier to heat in the winter, harder to cool in the summer. Not very efficient, but it's there.

            I don't know what effect power cycling a monitor has on its longevity, but I bet doing it once a day for twelve hours would increase useful life, not decrease it on average.

        • This is a common problem (called a split incentive) and why we end up approaching the energy manager and IT at the same time. Anyone can contact me through the website attached to my /. UID and I can get good info to help you get everyone on the same page.
      • I'm kind of going back and forth on this in my head. On one hand, reducing power to 12 watts sounds like a good thing. On another hand, a modern Pentium processor chews through way more than that on a medium load. Would the reduction is system performance be acceptable to the cost savings? Well, let's do some calcs. Let's assume that a modern PC with a CRT takes a constant 100 watts. (On the high side, I know.) Let's figure that out across 30 days:

        30 * 24 * 100 / 1000 = 72 KWh/month

        At the rates in Califor
        • Those look like pretty nice savings, but are they actually sufficient to warrant the switch over to a slower machine?

          Welcome to my hell...
          All jokes aside, it can be if your users don't need that sort of horsepower. And many do not, especially if IT has a very structured system and are conservative about upgrades, you could easily go three years with no image changes. This can make sense if the org is not obsessed with speed and performace which, in my opinion, many skew, needlessly so, that direction.

          • Re:Almost Brilliant (Score:3, Informative)

            by AKAImBatman ( 238306 ) *
            Honestly, the best solution for users that don't need that much horsepower is to switch to thin clients. With the thin clients, power consumption is easily under 12 watts per desktop, users can be centrally managed, and desktop horsepower can be upgraded in a single system replacement.

            I used to admin a Citrix network, and I have to say that the idea makes a lot of sense. Most of the issues with the setup stemmed from the fact that we were on NT 3.51 and not from the fact that our users were on a shared sys
        • Let's assume that a modern PC with a CRT takes a constant 100 watts. (On the high side, I know.)

          You've got to be kidding. 100W is on the low side for a modern PC without a CRT. A PC with a P4 (Northwood core) and a GF3TI200 consumes about 90W when idle. That's without monitor and without a "modern" graphics card which requires extra power.

          When playing a 3D shooter that system draws around 150W, still without monitor.
          • Modern computers go into various power saving modes when not in use. As a result, I'm using the 100 watt figure as a baseline average. Peak power usage on today's machines can easily get as high as 200-300 watts (thanks to the "latest and greatest" video cards).
        • "Those look like pretty nice savings, but are they actually sufficient to warrant the switch over to a slower machine?"

          The better question is do most people need these faster machines? If you are doing data entry and light spreadsheet work do you need more than even a P3? I will be honest I just setup a PIII with a low end Nvidia card and 384 megs of ram running Ubuntu. It is VERY USEFUL for everything but playing high end games. Video playback is and smooth and surfing is fast. For an average user a P4 is
        • Using PoE doesn't "magically" reduce the power usage to 12 watts. PoE can only provide 12 watts. You can't do a whole lot with 12 watts.

          CD/DVD burners are right out, especially rewritable media. Even for a laptop style device you're going to use close to 15 watts, and that leaves no room for anything else. You'll also be stuck with low power flash memory for data storage, which is slow and expensive.

          And unless you plan to provide seperate power, you're stuck with a roughly 6.5" TFT touch screen and nothin
    • Re:Almost Brilliant (Score:2, Informative)

      by cidco ( 240900 )
      POE wasnt really designed for everyday use, it was designed for manufacturers to have an easy way to power small devices on their control network. Seeing as many control networks are now going to ethernet rather than serial communcattions (DH+, Modbus+, etc). This allows them to remove a lot of the extra cabling from their orginal networks.

      Also POE is used in a lot of place s to power the wireless APs for WiFi.
    • rust me it will be adapted for WiFi. These things have a way of working themselves out. ;-)
    • WIFI:
      • great security (and I don't mean your network, I mean the network of Joe MCSE)
      • awesome bandwidth
      • no interference problems, ever
      The only advantage of WIFI is the lack of cabling. Unless you're talking about laptops, this is of little importance in an office as you need _some_ cables. At least until you get that Tesla rig working...
    • by imp ( 7585 )
      Soekris boxes have had power over ethernet for some time now. http://www.soekris.com/ [soekris.com].
  • Whoa... (Score:5, Funny)

    by TheSpoom ( 715771 ) * <slashdot@@@uberm00...net> on Friday April 29, 2005 @10:20AM (#12383098) Homepage Journal
    Was I the only one who saw that as powered by Pieces of Eight? That must be one expensive computer... but at least it recognizes that most people will use it for piracy.

    (Damn, I play Puzzle Pirates way too much. And yes, I know the answer to my question was yes.)
  • I find it more interesting the idea of a new PoE standard that will provide more power. Of course, those of us that have invested millions in the current PoE "standard" for VoIP and wireless will need to forklift everything.
  • by Anonymous Coward
    Nevermore, nevermore! I'll get a job at Best Buy before I support you power whores.
  • by utexaspunk ( 527541 ) on Friday April 29, 2005 @10:21AM (#12383108)
    I wonder which will work better- The Telltale Heart, or The Raven? Maybe The Cask of Amontillado?
  • by Anonymous Coward on Friday April 29, 2005 @10:21AM (#12383110)
    PoE = Peace on Earth. Purity of Essence.
  • Unlikely... (Score:4, Funny)

    by bodfa ( 656636 ) on Friday April 29, 2005 @10:22AM (#12383129) Homepage
    FTA: 'PoE could end up being a universal power supply system as the cables and connectors for it are the same all over the world. By contrast power sockets and plugs differ by country.'"

    This seems to fit somewhere along the lines of IPV6 and enough ip addresses for your toaster to be ip enabled. Yea... No toast today, the network is down.
  • by Hulkster ( 722642 ) on Friday April 29, 2005 @10:22AM (#12383131) Homepage
    Slashdot has discussed "Power over Ethernet: IEEE 802.3af" [slashdot.org] and how the Apple AirPort Base Station supports POE. [slashdot.org] There also appears to be a website dedicated to Power over Ethernet. [poweroverethernet.com] Ummmmm ... maybe I could use POE to power my christmas lights [komar.org] ... although I'd need a bit more than 15 Watts! ;-)
  • by Jurph ( 16396 ) on Friday April 29, 2005 @10:23AM (#12383141)
    ...is that the current equipment out there is probably not actually delivering all of the wattage that the specification calls for. For example, a cable modem draws about 20 [pmb.co.nz] watts from the wall; even if it's delivering all of that to computers on the network with no losses... then it can only support one of these machines without drawing power from somewhere else.

    • A cable modem that doesn't support PoE draws about 20 watts from the wall.

      Network equipment that adheres to the PoE spec has to draw enough power from the wall to power itself and the devices on each of its ports.

  • No GigE support (Score:2, Insightful)

    by nd ( 20186 )
    This works using the "unused" lines of CAT5. Sure, they're unused for 10/100 ethernet, but this will be much less useful once everyone is using Gigabit ethernet (which uses all 4 pairs).
    • by highfreq2 ( 575192 ) on Friday April 29, 2005 @10:45AM (#12383406)
      Actually, it works by put 40VDC between the TX and RX pairs. The coupling transformers block the DC before it gets to the PHY. It is compatible with gigabit. POE allows the use of the unused lines. This is needed for a seperate power injector, which can't touch the signal lines.
    • This works using the "unused" lines of CAT5.


      You can also use it on the Tx/Rx pairs as well.


      Because ethernet uses a differential signal. You can ship a constant DC offset over it, and it doesn't interfere with the signal in the least.
  • single Point of Failure? There, I thought you could.

    (I know that's PoF, not PoE, but hey.)

  • by Tree131 ( 643930 ) on Friday April 29, 2005 @10:25AM (#12383164)
    Not everyone has PoE at home, so this solution would only be ideal for businesses. You can of course always get a PoE cable that will plug in to the wall socket through a transformer and the ethernet jack, thereby combining the power, however that defeats the purpose of PoE, because most devices out there support both 110V and 220V, and they all have universal connectors and power supplies capable of handling whatever voltage you throw at them. An you'll still be plugging it into an electrical socket. You will also need a helluva lot more power to run processor intensive apps, so this would pretty much limit this machine to secretaries and web surfers/majority of home users - see above on why this is not a solution for home.
  • by Anonymous Coward on Friday April 29, 2005 @10:25AM (#12383169)
    So in the future everyone will be getting their power from ethernet cables and their connectivity through power lines [slashdot.org]?
  • PoE (Score:5, Informative)

    by karvind ( 833059 ) <karvind@gm[ ].com ['ail' in gap]> on Friday April 29, 2005 @10:27AM (#12383197) Journal
    I am not sure why is this a new news when the idea is around for sometime.

    The Power over ethernet [poweroverethernet.com] website which has links to articles and products (check the dates on some of the articles).

    A good article about ins and outs of PoE [nycwireless.net]

    Don't confuse PoE with Perl Object Environment [slashdot.org] or Poe Puzzle [slashdot.org]

    Nevertheless it is a good concept with lot of benefits (as well as drawbacks)

    Cost savings. PoE significantly reduces the need for electricians to install conduit, electrical wiring, and outlets throughout the facility. In larger installations, these items can be relatively expensive. Consider an installation of 50 or more access points. This requires lots of conduits, outlet boxes, electrical wiring and the time of a qualified electrician. The low costs of deploying PoE compared to traditional electrical circuits leads to worthwhile returns on investment.

    Flexible access point locations. With PoE, a wireless LAN designer has greater freedom to locate access points. You don't need to depend on only locations within short distances from AC outlets. The independence from AC outlets also makes it easier to relocate access points in the future if needed to fine-tune RF coverage or increase capacity. Thus, PoE enables companies to more easily maximize the performance of a wireless LAN.

    Higher reliability. Systems with fewer wires tend to be more reliable. With WLANs not using PoE, cleaning people may unplug an access point to use its AC outlet to power vacuum and buffing equipment. Electricians rewiring electrical circuits could inadvertently cut power to an access point. PoE eliminates the possibility of situations that disrupt the operation of the network.

    Enhanced operational support. Many PoE devices implement SNMP (simple network management protocol), which enables support staff to remotely manage the electrical power supplied to the access points. For example, support staff can disable a PoE-enabled access point by shutting off its power after detecting a breach of security. The temporary disabling of the access point can protect against an intruder from continuing unauthorized access to corporate systems. Other SNMP-based features enable the monitoring of the condition and consumption of power, which enhances the ability to ensure smooth and efficient network operations.

    Simpler international development. For manufacturers, PoE offers the benefit of the vendor not needing to provide different power cords for various countries. This not only helps keep the cost of access points done -- it's one less piece of equipment that installers need to worry about

    • So, if I use the power lines for broadband ethernet [hometownconnections.com], will I still be able to use this technology to power my computer, or does it only work for ethernet cables?
    • So, how much more will PoE network equipment and PC's cost than just putting in the electrical plugs?

      This might work in a new layout for wifi access points, but then you'll be restricted to WiFi components that fit this motif. Just bite the bullet and keep things flexible. The few sites that install this gear will be ripping up the place later to install power lines when they realize the new gear needs special PoE cat 5 (with 16 gauge wires)
  • By contrast power sockets and plugs differ by country.

    Which is why I carry one set of adapters for my laptop, and then charge my cell, palm, blackberry, and iPod via the USB on the laptop. Sure PoE might provide enough power to run a laptop, but it wouldn't provide enough juice to recharge the laptop batteries and all the other devices I need charged.

  • by Digital_Quartz ( 75366 ) on Friday April 29, 2005 @10:31AM (#12383242) Homepage
    "PoE could end up being a universal power supply system as the cables and connectors for it are the same all over the world."

    Don't you need a hub or switch which supports PoE? Ethernet sockets may be the same all over the world, but how many PoE-enabled ethernet sockets have you seen on a day to day basis?
  • We already have PoU [Power over USB] which was a rehash of PoS [power over serial/parallel] etc...

    I think it's good that we can use something like an already existing cat-5 network to power a computer though..

    In my case my USB powered 3-port cat-5 switch was handy when I was in France last as a quick-and-dirty means to a network. Can get ~50Mbit/s off it which isn't bad for 2.5 watts.

  • FTA: 'PoE could end up being a universal power supply system as the cables and connectors for it are the same all over the world.

    FTA?? That meaning F*ck the article??.

    Seriously, it would be nice to be able to charge your Laptop battery with the Network cable, although current notebooks have a 120~230 AC adapter, I think it is cumbersome when I need to connect: 1. the laptop AC adaptor; 2. the laptop network adaptor; 3. the 2 or 3 USB devices I have (camera, external HD, etc). I end with so much cables
  • PoE could end up being a universal power supply system as the cables and connectors for it are the same all over the world. By contrast power sockets and plugs differ by country.

    That's awesome! It solves the cable problem! I'll just plug my universal AC/DC power supply into....d'oh!
  • It's not like we don't already have power outlets near our workstations. It's not like 15 watts is going to power your computer AND your monitor. So, who really cares? This article could have just as easily been titled "New energy-saving computer produced - now you can lower your electricity bill this summer!"

    The general idea could apply, however, in situations where we already use PoE technology: places where it's a lot more convenient not to call the electritian in addition to the low voltage cabler. Li

  • Idea is great ! But doesnot seems to be practical with Computer having moitor,dvd drive,cd drive....etc. Even If we use USB device which is drawing power from the PC and ultimately from the network which can only supply a limited power. So no of USB devices connecting to the computer will also be very limited. Theoretically if a computer consumes Microwatts it can get power over wireless LAN...So no more Cables!
  • Just because you can, doesn't mean you should.

    While there are certain specialized applications where "power over X" is convenient, it shouldn't be used when normal power is available.

    • I know this is /. but maybe you could actually give some, you know, reasons? There may be some, but if you don't say we don't know.

      • How about safety, simplicity, cost and noise? As a general rule, I like to keep power lines isolated from signal lines. That allows each to be optimized for a single task. It keeps noise from being coupled from the power distribution system to the transmission lines used by signals. It keeps large current flows off of cables and connectors that were not designed for power distribution. It allows the use of standard (cheap) parts that have proven performance and reliability.
  • I was thinking this might be some sort of companion software to CRM114 [sourceforge.net].

    So many projects, so few acronyms.

  • Nice idea, but... (Score:3, Insightful)

    by Cyn ( 50070 ) <cyn.cyn@org> on Friday April 29, 2005 @10:39AM (#12383349) Homepage
    an ethernet plug is a lot more fragile and prone to 'not snapping in properly' than your average power plug. If some critical control system is powered properly, and disappears from the network, you plug it back in. If it was getting power over that same cable, it now has to boot back up, reinitialize, and figure out where it left off.

    Don't get me wrong, it's a nice thought - but personally I've run into a fair variety of RJ45 jacks. Maybe this would finally snub out those people making the shitty ones, so I'm all for that.
  • The REAL solution (Score:3, Insightful)

    by zakezuke ( 229119 ) on Friday April 29, 2005 @10:41AM (#12383367)
    Establish a GLOBAL standard for power and just go with it. Why not just 12V DC, the already established standard for autos. PoE is such a mickey mouse solution as others have already pointed out will likely confuse people. Pick a plug... anything in the 10mm size should be just dandy.

    Perhaps someone who has wired their house for low voltage would share their solutions. IIRC you couldn't have low and high voltage in the same gang box according to the NEC (National Electrical Code - USA), which is unfortunate as that would be the obvious way to get wall current and convert it to low voltage which is apparently a NO NO.
    • Re:The REAL solution (Score:3, Informative)

      by belg4mit ( 152620 )
      12V is no longer standard for cars [technologyreview.com]
    • well, first of all, the loss of power is much greater with voltages like 12 V than 230 V and so on, besides I prefer to have 1-2 amps to my computer instead of 20.
    • Re:The REAL solution (Score:3, Interesting)

      by epall ( 632054 )
      I actually have a small-scale solar power setup that powers my 17W server, our gateway router, my Palm charger, and a few other things all directly at 12 volts. The whole setup is 12V and we have "power busses" throughout out house for LED and stuff. They are two strips, one of copper, one of aluminum. The positive side is copper with female spade connectors. The negative side is aluminum with female bullet connectors. Sound safe? Yeah, it's pretty homebrew but I make pretty real-time graphs and it works we
  • by sysadmn ( 29788 ) <.sysadmn. .at. .gmail.com.> on Friday April 29, 2005 @10:41AM (#12383370) Homepage
    for the vendor. What this overlooks is that there is a reason designers select proprietary power and data cable connections. It gives that vendor a head start in selling you all the other useful things that plug into that port. The worst offenders are cell phone and pda makers. Notebook vendors are almost as bad. Commodity players might have a reason to adopt a standard to drive costs down, but lots of others do not.
  • by adzoox ( 615327 ) * on Friday April 29, 2005 @10:45AM (#12383402) Journal
    I've always liked the iPod ACs that used firewire cables to charge the iPod & thought Apple (to save money and promote firewire) should standardize all their ACs to this spec and same look.
    • You can do the same with USB and RS232 [iirc] and Parallel by sinking off a status bit or two (limited to like 25mA though).

      Back in the day I've seen things like sound cards working on game ports, serial or parallel. People used what they had available ;-)

      The big change in IEEE1934 and USB is that the power draw is actually standard [e.g. 500mAh for USB] and not just "common".

      My Creative Micro-Zen player charges either off an AC adapter or a USB connection. It uses one connection though on the player [
    • I've always liked the iPod ACs that used firewire cables to charge the iPod

      Old technology really, but mentioning Apple got you your mod points ;-) I've had charging USB devices for at least three years, and an access point that uses PoE for at least as long. The AP mains adapter terminates with a box with two cat-5 sockets on it. One goes to the switch, one to the AP (with power). I've often wondered what would happen if I plugged it in the wrong way and sent the power to my NIC/switch... :-)

  • by WaterBreath ( 812358 ) on Friday April 29, 2005 @10:48AM (#12383441)
    Wait a minute! I thought the next big thing was ethernet over power, not power over ethernet!

    What's going on!?

    Oh no... I've entered some sort of "Bizarro World" haven't I??? A world where technologies are turned backwards and inside out without warning! What a terrifying prospect!
  • It's a very cool idea, but I don't know much about PoE so take this with a grain of salt... if you're putting out DC power over a network cable, won't it be quite limited in the distance it can go?

    However the idea of carrying around a battery-less computer and just plugging it into a network is kind of interesting..
    Though I'm having a hard time thinking of *serious* advantages.
    • Re:distance limit? (Score:2, Interesting)

      by ajnsue ( 773317 )
      I wonder with time whether this will have applications in the server room. Heats a major issue in most high capacity rack systems. The idea of not having to add more HVAC capacity and PDU access for every additional server is pretty cool. Plus no big issue with power hogs like CPU's and disk drives -as long as you keep the storage separate.
  • There are lots of PoE-powered computers: switches, access points, etc. Many of them have processors running at over 100MHz and many megabyte of RAM--more than powerful enough to run software satisfying the computing needs of most people.

    So, the only reason why a PoE-powered computer is "amazing" is because what is sold as a PC these days requires a lot of power, and it requires a lot of power because Windows requires a lot of memory, disk space, and CPU.
  • PoE is a kludge! (Score:5, Insightful)

    by wowbagger ( 69688 ) on Friday April 29, 2005 @10:55AM (#12383529) Homepage Journal
    PoE is just another kludge being standardized because the industry is too lazy and stupid to define a proper standard.

    Ethernet cables were designed to carry DATA, not power. Running a 12W computer off PoE with any kind of distance to the power providing hub is going to require about 20W of input to make it work - with the 8W difference going to heat the cables.

    With all the concern over the leakage current of wall warts, this is an improvement?

    Consider the history of bad decisions like this:
    • "Power Points" in cars. Lighter sockets were designed for lighters, not laptops. They have poor mechanical retention (because the lighter needs to be able to pop out when hot), high contact resistance (so what if the contacts get hot? They are SUPPOSED to get hot!), and a really nasty failure mode (Lil' Billy dropping a penny in them while he waits for mommy to get out of the store). But rather than defining a sensible power connection, the automobile industry lazily continue to push lighter sockets as a power point.
    • USB port powered devices which provide no USB functionality. USB Humidifiers? [thinkgeek.com] Cup Warmers? [thinkgeek.com] Christmat trees? [thinkgeek.com] Ash trays? [thinkgeek.com] Cell phone chargers? [calcellular.com] USB was designed to allow your computer to *control* things, not act as a glorified wall-wart!

    Now we have this stupid idea. "But Ethernet is standard world-wide, and power jacks aren't!"

    So? How about coming up with a standard power/data services jack and deploying it? It's not like Ethernet jacks were a natural phenominon - they were a standard which was created and deployed.

    A nice standard power/data jack, with a standardized supply voltage high enough to move a reasonable amount of power through reasonably sized wires, and a data services jack designed to *move data* would be so much nicer in the end.

    Also, consider this: You have your plant with a bunch of these PoE computer terminals, each tapping power from your central hub. Each computer will inject a small amount of noise onto the line - that's just a fact of life. How much will that noise start to degrade the network signal - especially when you start talking about gigabit Ethernet?

    What if we just standardize on, say, a pair of Anderson Power Pole [andersonpower.com] connectors supplying 24VDC at 2A max, right under a standard RJ-45 Ethernet jack. Devices which want to pull power and data have a combined plug which mates to both sets of connectors, standard Ethernet devices use the top port only. Standardize on using 14 gauge wire for power.

    Now you have a sensible standard power port that can be used internationally, still requires the user to just plug one thing in, and isn't a kludge!

    (O.T. What is with /. suddenly deciding to replace </li> elements with </li><li> ? It screws up making proper HTML lists!)
    • A nice standard power/data jack, with a standardized supply voltage high enough to move a reasonable amount of power through reasonably sized wires, and a data services jack designed to *move data* would be so much nicer in the end.

      Yeah, so now what we all need is another different cable/connector standard so we have to make holes through the houses/companies... also, if you remember Ethernet/RJ-45 connectors where not "Universally proposed defacto standards", they are more acquired standards, and what P
    • by mpe ( 36238 )
      Ethernet cables were designed to carry DATA, not power.

      Using the same cable to carry both data and power has been going on for a century.

      Running a 12W computer off PoE with any kind of distance to the power providing hub is going to require about 20W of input to make it work - with the 8W difference going to heat the cables.

      This isn't a problem with telephone cables. Which tend to be both longer and of poorer overall quality than network cables. Ethernet has a maximum length of 100 metres as opposed t
  • POET (Score:3, Informative)

    by belg4mit ( 152620 ) on Friday April 29, 2005 @10:58AM (#12383556) Homepage
    The only thing I could fond on their site POET [dspdesign.com]. Apparently stands for Power Over Ethernet Touchscreen.
  • by MsWillow ( 17812 ) * on Friday April 29, 2005 @10:59AM (#12383566) Homepage Journal
    Power Oveer Etheernet. Makes sense, I guess. Far more sense than what I thought. :-/

    The last time I'd seen "POE" was in my favorite movie, "Dr. Strangelove," when the whack-job Air Force General launched a nuclear attack on Rusia, using "POE" as the code on the CRM119(? may have the number wrong) discriminator to verify that any radio signals were correct.

    POE came from two phrases the general had scribbled on his note pad - "Peace On Earth" and "Purity Of Essence." I was trying to figure out just how a computer could be powered by Purity Of Essence, especially given all the pr0n online these days :)

    My bad.
  • FYI on PoE (Score:2, Interesting)

    by smilheim ( 804292 )
    You have a few options with PoE.

    One thing that I really like is a lot of our resellers just purchase one large UPS for the PoE switches. If the power to the building goes out no need for remote devices to be plugged into indivual UPS's.

    Mid-Span hubs, for those who don't want to upgrade their core switches install these between (mid-span) backbone switches and PoE devices. Usually having data and data+power ports. There are also PoE switches where all ports can be configured to support PoE.
  • This sounds like the perfect type of computer to use as a thin client, such as LTSP [ltsp.org] or perhaps ThinStation [sourceforge.net]. No local maintenance, not even any local power requirements. Just plug into any PoE jack and go.
  • Great! (Score:3, Funny)

    by apilosov ( 1810 ) <alex@pilosoft.com> on Friday April 29, 2005 @11:18AM (#12383767) Homepage
    Now I can replace my entire datacenter facility breaker/PDU/rectifier bank with a single 6509 and PoE blades! Plus, it'll also route packets!
  • by hal2814 ( 725639 ) on Friday April 29, 2005 @11:22AM (#12383804)
    A few years ago, our department was too cheap to give us proper CAT5 testing tools. We used to stick our tongue to the wire to see if it was connected to the switch. Glad nobody implemented PoE back then or we would've been in for a shock.
  • Description (Score:5, Funny)

    by Spy der Mann ( 805235 ) <spydermann.slashdot@ g m ail.com> on Friday April 29, 2005 @11:33AM (#12383919) Homepage Journal
    (In case it gets /.'ed)
    Here's a layout of the keyboard used by this low-power computer:

    123 =
    0.C CE
  • by Momoru ( 837801 )
    Thats alot different then most computers which are powered by a PoS (Windows)
  • No (Score:4, Informative)

    by RzUpAnmsCwrds ( 262647 ) on Friday April 29, 2005 @11:41AM (#12384025)
    "By contrast power sockets and plugs differ by country."

    Wrong wrong wrongedy wrong.

    Yes, different countries use different mains sockets, and they use different voltages / frequencies.

    However, nearly every computer built in the last 10 years has a multivoltage / multifrequency power supply, and they always have the standard IEC socket.

    When building a rack system, computers are connected to special power strips that have IEC sockets. Regardless of country, the cabling stays the same.

    With Active-PFC power supplies, the voltage selection is automatic. Most notebook power supplies have automatic voltage selection as well. Heck, even my cellphone can run on 220V/50Hz.
  • For broad general adoption EoP makes more sense to me than PoE. Every single room in the US has a power outlet in it. So, run the network through the power wiring and make devices that can access it.

    Cat5 is more expensive and less plentiful than electrical wiring and parts. Everything needs power.

Houston, Tranquillity Base here. The Eagle has landed. -- Neil Armstrong