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ReLik writes "The BBC has an article regarding power supply via networks. 'Instead of needing adapters, computer networks could soon be supplying the devices they interconnect with both data and power. Some makers of network equipment are already putting the power via data cable system into their products. The basic plugs for computer networks are the same all over the world, raising the possibility that powered data cables could become a universal back-up power supply.'" We've talked a little about specific 802.3 spec advances previously.
What about all the physical threat this brings up to a common user? Hullo!
... he'll re-define the term "firewall"
Now we just need to make it wireless for the power and the data and the keyboard and the mouse... whoo hoo!
This just calls for ddos attacks on LAN ;-)
There better be some good power overcharge protection included ^_^
I wonder if they'll be sending it as straight binary or xml.
Firewire? USB?
Both HIGH SPEED/POWER, AND FULL SPEED/POWER... and the as-yet-unreleased LUDICROUS SPEED/POWER.
This is just another case of the Brits trying to steal our momentum... those bastards.
Black and grey are both shades of white.
states that if you rub two sticks together you get fire.
Seriously, how long have did it take people to release there is a current in their ethernet cable? I known of products (home made and retail) that have been around for years that utilise this power supply.
How effective would this in a world striving to move to wireless protocols?!
It wouldn't get the chance to make a scratch let alone a mark.
There are two kinds of egotists: 1) Those who admit it 2) The rest of us
I admit I don't quite know the exact ins and outs of this technology, but a few things do come to mind:
Wouldn't supplying substantial amounts of power through network cable (lets say cat5) make enough EMI to scramble the data going through the other pairs?
Also, would this work in situations using coax cable, where there is no other pair?
Lastly, can you put 120VAC along wires that thin without causing lots of power loss and making a lovely fire hazard?
If you can't see the value in jet powered ants you should turn in your nerd card. - Dunbal (464142)
Here is some info by POE from NYCWireless...
Now just give me wireless repeater base stations powered by tesla coils and I'll be in heaven.
Yup, you'll now have to get a licensed electrician to punch down that patch panel, unless you don't mind fried IT people piling up at the bottom of your 19" rack.
-- Thou hast strayed far from the path of the Avatar.
no one plugs in legacy equipment
*sounds of sizzling and a faint smell of burning plastic
...is now as simple as feeling how warm the ethernet cable is.
Imagine, getting the power your laptop needs over a wireless network - that would keep you on your toes!
Golden rule of data cable laying:
Avoid power cables! If you've gotta go near the buggers, cross 'em at right angles.
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
> The fact that network devices are sitting only
> on a data cable makes it easier to manage them
> and reboot them remotely, said Mr Lehr.
huh? What does the POE (power over ethernet) do
to help a remote reboot? Many devices that use
POE (Eg 802.11 Access Points) can anyway be
rebooted using the web interface or SNMP!
The real advantage is in terms of space saving
and cost saving (not needing a power outlet in
every place you put an AP), having to drag just
one cable to the false ceiling behind which your
AP resides!
These guys make a GSM/GPRS base station that is powered over Ethernet.
Cool huh?
-- Mike
Call Roto-rooter!
Also, the available power will be pretty minimal. IIRC it's a max of 65W, and the gauge of Cat5/6 cable isn't up to high current applications.
Oh and I can't see this working with Base-FX either, funnily enough.
"God, root, what is difference?" - Pitr, userfriendly
So.. we have power over data lines and data over power lines..
:)
What a world, I'm so glad to be alive in 2003
Excuse me, I don't mean to impose, but I am the ocean
Did I RTFA right? Why does an electric shaver need an RJ45 connector? Why does it even need more than one cable (the power cable)??
WTF is all this "Alter Relationship" all over the place?
Anyone know how much current the new spec allows? (yes, I did rtfa and it's not in there) I don't think Cat-5 (or similar) cable could carry much current, but I could be wrong. Since it can power a razor, I assume it would be enough to power basic ethernet devices, but I'd still like to know the exact specs.
An Indian-American Hindu committed to non-violent thought/speech/action alarmed by the global explosion of radical Islam
We'll have all the power any device will need in a tiny antimatter cell.
-Libertarian secular transhumanist
This does not look like it will be used for anything larger then small hand helds and other similary sized devices. Cat 5 is normally 24 AWG which has very high resistance per foot making long runs useless. at around 50ft you might have about 4 or 5 ohms. Unless you have 2 or 4 pair cat 5 with a pair of 18awg or larger in the same jacket it doesent have much use for anything drawing more than 10 watts or less. although making such a cable wouldent be such a bad idea.
Would be cool to have some type of hybrid connector that carries 12V @ 10 or 20A (or maybe more volts to carry more power) with ethernet and switches can become both ethernet and power supplies. Small server farms or disk arrays etc. could be attached using just one cable for all functions.
Ok, so maybe this wasn't exactly what they were talking about. It's still kind of fun though...
The Etherkiller
REAL Ultimate Power!!!
EEs are sooooooooooo sweet that I want to crap my pants.
Facts:
1. EEs are mammals.
2. EEs solve equations ALL the time.
3. The purpose of the EE is to flip out and write MATLAB code.
I can imagine it now, power suddenly fails, PC & other devices start using their ethernet to provide power to their machines, switches would probably think thats alright, but the poor UPS that power the stacks of switches might just go BANG .. so, largish company, 150-300 devices, powered by a UPS... really?
heh.
-Rob
-Rob
"The RJ45 connector is a universal outlet," he said. "It's the only one identical in Asia, Europe and the US."
The same is true for FireWire and USB, and those are far more widely available. In fact, USB is increasingly becoming the standard for recharging portable devices, with USB power cables for most PDAs and cell phones available. FireWire might be better for this than USB because it can deliver more power, but maybe the USB standard will catch up.
You can even get a USB toothbrush.
The RJ-45 connectors used with Ethernet really don't do it for me; I think both USB and FireWire connectors are far better designed. I think POE (Power over Ethernet) will remain a niche market.
There have been quite a few posts so far about how running power over data lines is a bad idea and would cause all sorts of bad EMI, killing the data signal. But it actually doesn't. The power going through these is low-voltage DC (I think 12v), *not* high-voltage AC like wall power. AC produces changing magnetic fields which cause EMI, while DC produces a static magnetic field, so the data could care less. This is the same way that USB works (at 5v) and even POTS (plain old telephone systems...those have a full 48V DC...not always very nice when you forget that fact doing wiring). I haven't actually played with any of the equiptment myself, but from what I've read everything is low-voltage and low-power enough not to cause any sorts of problems at all.
Now this could be interesting. I worked on a system that toasted three Ethernet cards before we got a clue and stuck an isolating piece in the middle. It was on a long loop of thinnet cable which connected several buildings at a high school.
I suspect many of the buildings had separate power feeds and therefore different grounds due to being built gradually over the course of 40 years or so. The potential eventually got us, and cost us a few bucks and a lot of lost hair.
They had better be very careful with this stuff. Interconnecting building grounds over your network cables is a good way to fry equipment and unsuspecting people.
Check out the prelimary specs for 802.1u - power over wireless ethernet. They are planning on using microwaves to send the data and power to wireless devices around the home and office.
When information is power, privacy is freedom.
You know, this is a cool idea, but the true killer app is when they bring this technology to 802.11.
Oh wait...
Doesn't it seem practical that separating data from power is an essential property for data security? Ever seen The Recruit:
http://us.imdb.com/Title?0292506
Sounds like Ice9 to me.
-=- Many seek good nights and lose good days.
Wouldn't supplying substantial amounts of power through network cable (lets say cat5) make enough EMI to scramble the data going through the other pairs?
If it's DC only and well filtered/buffered, no. If it's RF, or DC that's not well filtered(noise is generated from any kind of switching, even in low power ICs). Buffering it isn't that tough- you can sorta think of it like a bucket under a faucet. As long as your average water needs over time don't exceed the flow out the faucet, you can take whatever you want, even large amounts suddenly, without causing pressure changes in the rest of the house. Now, imagine drawing a cup of water every once in a while from a faucet directly and shutting the water off really hard- helloooo water hammer!(similar things happen when you switch on/off power down a long line, or to/from an inductive component.)
Also, would this work in situations using coax cable, where there is no other pair?
Actually, Dallas Semiconductor(now part of Maxim) came up with what they call the One Wire protocol; it only needs one line for power+data(hence the name, even though you still need some sort of ground.) It's a pretty well set up system, works nicely- plenty of info on the web and their site, and there's even guides on designing a proper network- and shows the effects of cable length on things like pulse smoothing, noise, etc caused by communications and device power draw. It's VERY thorough.
Lastly, can you put 120VAC along wires that thin without causing lots of power loss and making a lovely fire hazard?
Actually, power loss is less with higher voltages- that's why high tension wires are tens of thousands of volts. P = I * V; 100W at 120V is .83 amps, but at 12v, it's 8.3A.
This is important, because the higher the current, the higher the voltage drop; V = I * R. All wire(except superconducting) has some resistance, and the lower the current, the lower the voltage drop end-to-end, and the lower the amount of power(heat) the wire absorbs. Wire(or perhaps more accurately, cable) is rated in terms of maximum voltage mostly from the insulation type(its dielectric strength) and current- its gauge, or thickness of the solid or stranded bundle(larger #'s = smaller thickness).
This is one reason automotive manufacturers want to go to 48V systems; the wiring between the battery and main bus/alternator can be much thinner, for example. Take a look at your battery cables some time- they're VERY heavy gauge. Also, as previously mentioned, stuff like dirt on contacts and corrosion between clamps+terminals or in splices are much less bothersome at lower currents.
Please help metamoderate.
To achieve reasonable distances and power, the voltage will need to be highish.
This reminds me of an incident that happened about 15 years ago. We had an ethernet cable between two buildings. The cable was terminated on computer chassis on each end. Unfortunately the two buildings were powered from different phases, so when I opened a connector I became part of the ground loop passing mains. This was not in USA, but was in a country with real (>200V) power.
Engineering is the art of compromise.
Umm, hello...
Can anyone please tell me what the point of putting real juice down Ethernet would be? Isn't Ethernet like 30 years old? Why don't we come up with a new FireWire/USB type plug with a configurable interface, set it up with +5V, +12V, Ground, Data Send and Data Check, set up generic, open hardware-level frames capable of wrapping all other protocols and a spankin' new cable/plug combo which would shield the voltage lines? I mean, Christ, let's move on. Why are people still talking about Ethernet? Oh, and a better endplug would be nice; one that releases with a sharp jerk, stays put with a slow tug and has a satisfying, soft "click" when engaged.
I realize I will get downmodded for this, but I am being quite serious.
One problem, and maybe its been mentioned already, but its pretty darn easy for flesh to make contact with the copper on an RJ-45... I know that I'd have a great deal more respect for the patch panel if I thought I could get 120V AC at multiple amps just by being careless with the Cat5.
Yeah, big deal... let me know when they develop power-over-WiFi.
I don't care if it's 90,000 hectares. That lake was not my doing.
and by saying "utilise" he sounds like an ignorant dolt repeating the jargon he's been indoctrinated with (...imho...)
MacWireless.com sells a cable setup to allow you to do this now with your base station.
At $30 a port it is a LOT cheaper than going with a Cisco POE solution for base stations.
What, me worry?
Seems to be some interest, so here's a few comments:
:)
802.3af is a nice little spec; it covers a number of different options. I'm not an electrical guy, so I can't spec the power, but it's low voltage, low wattage. You have to do this for all sorts of reasons, not the least of which is that if the voltage is high, you run into local municiple code issues!
Us networking types don't want to get taking over by IBEW.
The most common usage is power on pin 4,5,7 & 8: the pairs not used by ethernet. This is the type of power most commonly provided by in-line power addition devices, becuase you're "pretty sure" there's nothing on the other side on those wires (unless there's gige in use, of course). The spec says that this is the recommended type when a device injects power between the switch and end device.
A growing usage is to provide power on 1,2,3&6, which the detailed reader will note is also the pairs used for 10baseT and 100baseTX. The trick here is that, just like a switch/hub looks for a link pulse before it brings up link, it also looks for a specific tone to be looped back by the device before it provides power. No loopback tone, no power back, no dead ethernet card.
The biggest confusion with this technology, though, is pre-standard implementations. Cisco's existing Cisco Inline Power standard is very very close, but as usual, not exactly the same (it depends on CDP for some aspects to function, and you have to license CDP, so...).
Many use the unused pairs; this isn't so bad. Few things can be hurt by that.
Cisco's 76xx IP phones can take it both ways, over the unused pairs or data pairs.
There IS a catch with those phones, though-- I'm told they reverse the pins for power compared to the spec, so an dongle is required in line for your IP phone so that it gets the right power from a TRUE 802.3af compliant provider. I'll ask arround-- a coworker has the dongle, but I'm not 100% sure which cisco product it's for (for those wondering, this is different than the power-injection device).
with swiches, 802.11 APs and with IP phones.
s 663/products_data_sheet09186a00800924d0.html & http://www.cisco.com/en/US/products/hw/wireless/ps 4570/prod_quick_installation_guide09186a00800a3fe1 .html for examples.
See http://www.cisco.com/en/US/products/hw/switches/p
so the RIAA can blow up your PC?
Your PC blows up the RIAA!
FIREWIRE
:)
:)
Been there, done that. GREAT IDEA though...
With that said -- yes, I know that my 10Mbit Internet running at 5Ghz is back feeding the antenna power. Yeah, it's nice to see 900K/sec @ home -- and it's slowly taking over our branch offices as well.
I had one office that wanted a whole bunch of Snap! servers (cute, but I personally don't find their file system to be enough). Instead of trying to having umteen million power adaptors plugged in I rigged power originating @ the switch to feed the servers. On the server end just added in Radio Shack wired plugs. Not a big deal as I usually cut my own network cables/test to this day.
Forget the ratings -- a good Amp meter, a little time, and powering everything on together tells all you need. What the amps and voltage is voltage. About time.
Wait, PRIOR ART, did I patent the idea? Damn. Could have sued.
My only potential concern in the future would be trying to mix already network powered devices with this new fangled technology.
Garbage In Garbage Out
.350 A = 16.8 watts
The article talks like this is new, it is not Cisco and Symbol have done it to power APs for years.
It can not be 120 / 240 AC the connector is wrong.
an RJ connector can not handle much current.
So the POWER (volts * amps) will be limited. So you are not going to power you internet enabled stove from it. A lap to may be a strech.
my Sony 19.5V * 3A = 58.5 watts
prev post 48v *
Nope
"The humble RJ45 could have a big future" That would be an appropriate statement for the late '80s, yes. (unsure of the exact date of RJ45 standard )
So if I have ethernet over my power lines, and power over my ethernet lines, I dont' need either right cord to have both? err.....
ok, can't you see your PHB actually wondering that?
So, now: slashdotting = firebombing someone's house or server room. Once 900 trolls hop on the bandwagon, a server will literally go up in flames!
The very first time someone plugs power over ethernet into a non-power over ethernet hub or switch.
-ted
It means some one stuck a pea up your ass last night. I am sure this raises more questions than it answers.
Oh great,
"So we want to make sure that some of them are different..."
I love the possibility of different countries opting for different voltages. That way you can chance frying your laptop every time you travel.
Xix.
"Everything is adjustable, provided you have the right tools"
I'll be impressed, and get a warm fuzzy feeling, when they have power over wireless ethernet.
Laugh while you can, monkey-boy!
Check out Lemo for endplugs (warning: flash). They make the best, hands-down. I once soldered up a patch panel with 1200 of these things...it was a work of art.
Great! So, now, when my power goes out, my computer can instead draw power from the network cable. That cable will in turn receive its power from the hub, which is plugged into... umm... the wall... with no power. Hmmm...
No, no, the hub will get its power from the network cable from my DSL router! And the DSL router will get power from the phoneline providing the DSL. Hmmm... no, wait, not enough power.
Oooh oooh! I know. The DSL router will obtain power from its network connection to the hub, which will get its power from the network connection to my computer, which gets it from...
im looking under my desk now at a full power strip - im seeing a few pounds of wires and a huge mess
and then i have those network cables of course
well - i guess apple will be the first - let us see how it should be
http://en.wikipedia.org/wiki/2004_U.S._Election_c
Ok, so there's power over ethernet, and broadband over power, and voice over IP. Convergence?
Does this mean I could harvest all my spam and use it to power my house?!?
...this maybe? Very nice POE converter by NYC wireless. Tested out to 250 feet. Not exactly the same thing but still cool, and proves you can put useful power in the pairs without causing issues.
Just wait until some intern or **ERe*HEM*manager**COUGH** kills an older (router without the Power over ethernet ports) Cisco "Washing machine" or "refrigerator" series router by plugging this into the Giga-bit ports :) God will my job be fun...spraying it with the fire extinguisher, then running from the halon extinguishing system while saving the intern from the inferno, calling an ambulance, pulling the intern's mangled corpse from the flames, submitting a price estimate, buying a new router, having to lift the router up without the aid of an intern, configuring the router, finding a new intern...then repeating. I think Cisco stock is about to skyrocket! And think of the job market! Our troubles have ended, we can all be interns!
Note to Cisco: Should this fly, sell a RJ-45 port protector and code name it "downyball" to protect the "washing machines"!!
It will be interesting to see what the range of this is. If it is sufficiently large it should make home automation networks much easier to do.
You would string ethernet everywhere and then would be able to add sensors, switches etc. without having to get power to them by another route.
Microcontrollers with embedded ethernet are now pretty cheap (and small). The home automation network could then use the same wiring as the home computing netwoek.
Yeah... and since it's the same type of connector all over the world, why don't we start to manufacture fridges which plug into the network-cable, only to get power.
- What if you're on WiFi?.
I'd guess that you still have to use an ac-adapter for those moments. But if it'd be possible to standardize so that you plug the network-cable into the ac-adapter, and the ac-adapter in the laptop... a bit clumsy but it's only for the times when no power is available through the network. When it is, plug the network cable directly in the computer. No adaptaer between.
h
A lot of USB devices pull their power through the cable...this isn't revolutionary.
When I am king, you will be first against the wall.
POTS lines have always done this.
Thx for the link... Now I want one.
a wireless protocol so I can tap on my neighboor's electric network :)
-- Leeeter than leet
I'll finally get rid of this mass of cables resembling a 'Borg cube's innards behind my desk running to my KVMs. I'll replace them all with a mass of CAT5 that will look much nicer won't it?
Well, at least it will be about half the number of cables to keep track of.
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