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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 know you were kidding, but wireless power Does exist. T
So in the future everyone will be getting their power from ethernet cables and their connectivity through power lines?
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
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.
Who are you? The new #2 Who is #1? You are #617565. I am not a number, I am a free man! Muhahaha.
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.
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