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New Computer Powered By PoE
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.'"
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. :-/
Javascript + Nintendo DSi = DSiCade
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.)
It's better to vote for what you want and not get it than to vote for what you don't want and get it.
- E. Debs
Nevermore, nevermore! I'll get a job at Best Buy before I support you power whores.
I wonder which will work better- The Telltale Heart, or The Raven? Maybe The Cask of Amontillado?
PoE = Peace on Earth. Purity of Essence.
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.
Slashdot has discussed "Power over Ethernet: IEEE 802.3af" and how the Apple AirPort Base Station supports POE. There also appears to be a website dedicated to Power over Ethernet. Ummmmm ... maybe I could use POE to power my christmas lights ... although I'd need a bit more than 15 Watts! ;-)
...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 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.
I know you were kidding, but wireless power Does exist. T
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).
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.
So in the future everyone will be getting their power from ethernet cables and their connectivity through power lines?
is 35 watts enough to run most laptops?
Considering that my iBook uses a 65 watt charger, I'd say that 35 is probably sufficient for anything short of the "Desktop Replacement Laptops" (relly more of a portable desktop). My guess is that the laptop will most often run below 35 watts, then trickle-charge the excess to the battery. If the computer needs extra power in the short term, the battery will provide it.
Javascript + Nintendo DSi = DSiCade
The Power over ethernet 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
Don't confuse PoE with Perl Object Environment or Poe Puzzle
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
"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?
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!
Uh, fewer cables and redundant AC/DC converters (wall warts)? Why does every single device need to have a heavy power-processing unit to do the same task of AC/DC conversion? Do it once and make many devices share the low-voltage supply.
[
The ethernet port *is* the power input. RJ-45s have 8 connectors. PoE uses some of the spare conductors to provide power, the rest still do data.
ObRTFA:
Power-over-Ethernet (PoE) works because when data is sent down network cables it is represented by voltages. PoE uses spare wires in cables that link computers back to network hubs and pump power down these, separate from data traffic.
Random and weird software I've written.
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.
cyn, free software and *nix operating systems enthusiast.
easy, plug in more lan cards.
This signature is a waste of 42 characters
No. Gigabit ethernet uses the same pairs as 10/100 ethernet.
No. 1000Base-T (802.3ab), or Gigabit Ethernet, does indeed require all four pairs (8 conductors) of the cable.
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.
There is no sanctuary. There is no sanctuary. SHUT UP! There is no shut up. There is no shut up.
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.
Envy my 5 digit Slashdot User ID!
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.
Yell & scream & rant & rave... it's no use... you need a shaaaave ~ Bugs Bunny
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.
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!
You sound like Nikola Tesla!
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:
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 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
www.eFax.com are spammers
The only thing I could fond on their site POET. Apparently stands for Power Over Ethernet Touchscreen.
Were that I say, pancakes?
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.
Lemon curry?
While neat in theory, and useful in certain applications, in general there are a few practical problems with making "many devices share the low-voltage supply":
1. Current flow goes up as voltage goes down (to get the same number of Watts). You don't want to be transmitting a high DC current because series resistance will eat your lunch: Current * Resistance = Voltage drop (aka V=IR, aka Ohm's law).
2. Following on #1, all the devices sharing one supply need to be relatively close to it.
3. Even for low current applications, different devices need different and sometimes multiple voltage rails. Do you supply them all, or just some of them make the target derive the others?
4. Following on both #1 and #3, DC voltage and more importantly, power requirements change over time, so in the end, you'd likely end up with what you have now... multiple DC supplies, some for older devices, some for newer devices.
Now, a number of these problems could be avoided if you used a high enough DC voltage (let's say 48V), but now you have a safety issue if high currents can be delivered, not to mention that each device would need to step down the 48V - so you end up with the same thing you have now.
-- PGP keyID: 0x4C95994D
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.
Sean Milheim
iDREUS Corporation
It's not expensive, but it may be a bit messy...
The revolution will NOT be televised.
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!
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.
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.
(In case it gets /.'ed)
Here's a layout of the keyboard used by this low-power computer:
789+-
456*/
123 =
0.C CE
------
"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.
Nice for some applications (think of public phone charging points / laptop tables with power + wifi) but its only just wireless. It's more like plugless, you have to be on the pad (though I wonder if it could be scaled up to power electric cars for instance, think about an electric highway!)
Tesla had a more practicle wireless power solution in his tower. That crystal radio that you built as a child is wireless power in my book, even if it is only a trickle. (You're not a geek until you build a crystal radio. Hope we never switch over exclusively to digital)
I have heard rumours about someone living under a transmitter being prosecuted after he was found with a large number of coils in his roof, using them to provide heat, but i have my doubts about this one.
Philip
Signatures are broken