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IP Telephony Drives in Power over Ethernet
GuitarNeophyte writes "The Channel Register states that although the idea for Power Over Ethernet has been around for a long time, the stage may finally be set for it to become an essential factor in our technical lives. One of the main reasons is because of the emergence of ip telephony. 'Telephones need to work in an emergency including when there is a power failure. Traditional telephones do, but IP phones will only do so if there is an uninterrupted power supply (UPS). The only practical way of guaranteeing power supply to a large number of IP phones is PoE.' Will IP telephones bring in PoE?"
...given the migration to Wifi, that is.
If you really want to keep 911 available, your solution is to invest this money into lots of wireless nodes instead, all with battery-backup, so that EVERYBODY has access regardless of the circumstance.
--
Why didn't you know?
Soon we can have power over wireless too.. yay. No batteries do not count as power over wireless
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I work for a school system in Maryland (Charles County) and we're implementing system-wide IP telephony at all 30-something of our schools (20 elementary, 7 middle, 7 high, plus several education centers and other facilities.) All our IP phones use PoE, so half the ports in each school are PoE capable.
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Tim
I wonder if this means we can have a better sound quality coming out of the telephones or if they are just going to keep the quality the same to use less power.
Apparently, my cousin has Ethernet over Power, that was installed by The Internet Service Guy...
...or maybe they would cancel each other out, and you'd just get regular ethernet? ...or maybe it would be like a divide-by-zero, and your NIC would explode? :P
It would be interesting to see what happens if you ran Ethernet over Power on a system powered by Power over Ethernet... who would win? an epic battle, to be sure!
It has at my office. It powers our phones and nothing else. We haven't had any fried motherboards or nics, but I'm waiting... hopefully in vain.
This will require UPS to be built into the Ethernet switch / router right? Or is it voodoo magic? :)
If there is a power outage, you still need a UPS and/or a generator. If switches don't have power, how can the phones have power? Just my measly 2 cents
It's all just part of the trend towards having one "wire" to take care of communication needs in normal and emergency times, so it'll probably become standard quickly, as long as you keep those magic words: "cost-effective"
That'll be great when there's a storm, and trees bring down the power lines.
I can't wait for the first virus that electrocutes the poor soul who has VOIP but forgot to get all of the hotfixes for Windows XP and still uses IE.
They had a major meltdown that lasted weeks for some of their customers.
And they're just one example. All VOIP providers have had significant problems at one point or another.
Yes, IPT will bring PoE, but it won't be good for much other than powering phones and WiFi AP's. You can only put a few watts on each switch port, or you end up with a switch that's more of a heater than anything else.
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I work for [Big Co. Inc.] and we have IP-telephones all over the place here that all use PoE. However, they simply use injectors right before each phone rather than use PoE from the switch.
Maybe someone can explain why PoE is so expensive. I wanted to get a 24-port managed Gig switch with PoE for my home but had to give up on that, the cheapest good one I found was around $1500, might have even been in the $2k range. Once I dropped the PoE requirement I got one for $500. I mean, this is simple DC injection isn't it, how can it possibly be so expensive to implement?
Although I have all my networking equipment on a UPS already, whenever the power goes out, so does the cable. Probably because whatever equipment down the street which supplies my cable internet feed runs on the same power my house does.
Getting power from my cable company won't help if they depend on the same power source my house does.
I'd say that we will eventually have PoE, but I don't think it will be a necessary consequence of VoIP or telephony. I have VoIP, but I use it exclusively for the three hours a day I work as a call desk support monkey for my company. If I had an emergency, I have my cell phone on me as well.
This is something I've wondered about a lot: how many slashdotters out there use VoIP as their primary telecommunications resource? How many would use telephony once x gets improved?
#define CLUE 0
I imagine we'll be seeing plenty of useless (but pretty) little blinkinlites and other silly gadgets built on RJ45 plugs, for keeping the dust out of unused router ports.
How about we run IP phones over modems on phone lines? Maybe if the telcos just had DSL to every home there wouldn't be an issue, then it would just be a matter of building the phones.
I remember a while back there was an article on Slashdot about how PoE can become an universal power standard. While there are different plugs and voltages used around the world, PoE has a standard jack. Sure PoE is low powered but with miniaturization, many of our devices can be powered off of PoE. With VoIP driving the spread of PoE, I hope this will build momentum in making the prediction come true. Imagine going to another country and needing to bring just a CAT 5 cable instead of a power adapter.
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Just wait for the first virus that electrocutes the poor soul who has VOIP but forgot to get all of the hotfixes for Windows XP and still uses IE.
humm i don't know about you but all the nice ip phones i have used are PoE - they might also have a power block option but they all work fine on PoE
it is quite nice.. mix it whit my cisco 2900-24 and it is like i have a siwtch and a pbx all in one..
now if only i could plug the t1 right into the switch - that would save me some time
'...if only "Jumping to a Conclusion" was an event in the Olympics.'
So what about wireless? I love my wireless router, and I don't think I could go back to wired connections unless I had to (I use a laptop, and it's easy to roam around my house without worrying about cables).
WTF ?
Power over Ethernet ?
Broadband over power ?
Has the world really gone topsy turvy ?
Quidquid latine dictum sit, altum videtur
Correct me if I'm wrong, but PoE would still require the power to come from somewhere. During a power outage, where will this power come from? Both the DSL modem as well as the Cable modem require power. The computer requires electricity to power the NIC. So unless you have a UPS, or you have a notebook, or you plug an inverter into the car, I would stick with a cellphone.
whats the point here? And PBX based "digital" phone lines pack more juice than a home line already. I don't like this 911 thing either... for 911 to work "right" they have to know right where you are right away... I don't like the idea of my IP being in a DB at the local cop shop 24x7x365, I know they can get it any time they want it now, but they have to take the trouble to go ask, this way, anyone in that call center has everyone in the area's IP addresses right in front of them constantly.
While VoIP will certainly push PoE, for us the big factor pushing it was deploying wireless APs. Pretty much none of the locations we were putting the units in had AC (not many outlets 8-10 feet up the wall), so being able to power them over the ethernet run was a major time and money saver.
We were facing the same problem and found it cheaper to inject POE right at the phone untill we found that you could buy a 24 port power injector for a couple hundred dollars off of ebay. Put these things next to your switch and inject it there.
Something is wrong with the math currently because a 24 port switch with POE is almost three times as expensive than a 24 port switch & a 24 port POE injector.
IP telephony drives PoE? Next they'll say that SUVs drive the oil industry.
Runnin' On Empty
At my office we've already switched over to new Cisco VoIP phones, which are powered via the ethernet cable. There is an optional DC plug for a wall wart if it can't power up via the ethernet cable. On a related note, when I called my parents today my call was dropped because their VoIP connection was too busy. So I still don't entirely trust the technology to be reliable, especially in emergencies, not to mention power outages in rural areas where when the power goes out, the ISP provider's (cable company's) equipment also goes down. If you have VoIP, I suggest a cellphone as a backup. But if you have cellphone with a reasonable plan, do you even NEED VoIP?
I worked for a large company, during my time there we made the switch to VOIP, with the nice Cisco phones. The whole deal was set up with POE to all the phones, which was great for a couple reasons: Power outages we could still use the phone (as mentioned in the article), one fewer cord on our desk (no power cord), one less stolen slot on the power bar.
/LOVE/ to see is POE being used on the desktop to maintain power to your RAM during a power outage. Obviously there is a chain of things that would need to support this in order for it to work, but on an enterprise level I think it sounds like a good investment. Once the power is restored everyone's machine turns on to it's previous state.
The server room manager guy was a big fan of this system because it allowed him to reduce the number of UPS protected outlets outside of the server room (some models of the desk phones used at the help desk required their own power supply), and since it was now his problem a boost to his budget.
Something I would
paul reinheimer
Now if I could just get that POE to Firewire to USB adapter to work....
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We've got to call those fighters back!
We want to have phones ( not just 911 ) available in case of power failure, so our network just got upgraded for just this thing. i hope it drives it because buying IEEE Std equipment still seems to carry an excessive price.
My office just completed moving to a new office building, and one of the things planned from the beginning was VoIP phones.
For VoIP phones to be useful in any way they had to be no more intrusive than a regular phone, but provide benefits. Power over Ethernet keeps the requirements for the phone down to a single CAT-5e cable, and a capable backend switch (we ended up going with an end-to-end Cisco solution for both phones and general network switching, which has worked out perfectly.) That and the system provides an on-phone phonebook for numbers as well as advanced message logging and voicemail abilities, all managed through a PoTS bridge, and the Cisco server.
This let us put only ethernet jacks in the majority of offices, and lets us plug the phone into ANY port and it works instantly.
So you might say that VoIP and PoE go hand in hand; PoE needs VoIP to justify itself, and VoIP needs PoE to make the devices unintrusive compared to regular phones.
Reading the article indicates that a UPS is still required at the switch.
What concerns me is if the FCC makes a ruling to the effect of "all VoIP solutions must continue to operate (to provide emergency services) during a power outage."
Will this force all of the moms-and-pops who are running VoIP on their home computer to buy and install a UPS before they'll be allowed to connect to a VoIP service provider?
- Dell SC800 - running Debian with Asterisk
- TDM400P - In the Dell server
- Netgear FSM7326P - 24+2port POE one of the first large POE switches (yes i know, cisco, but they are mega bucks)
- Grandstream GXP2000's for everyone
:)
- APC 1500XL UPS - runs all of the above during a power outage
That setup has worked perfectly during our frequent poweroutages ( we have one about every month for about 45min )If POE hadnt been avaiable we wouldnt have even been able to consider converting to VOIP!
"I reject your reality, and substitute my own" - Adam Savage
We recently implemented a medium size lot at our shop...around 160 IP phones.
One thing that's really annoying is the 'bridging' factor in the phones. Seems most people freak at the cost of needing twice the Ethernet switch (not to mention if a large number of catV runs are required), so these phones bridge the connection from the PC.
In our phones, when you bounce the phone you bounce the network connection to the PC due to this bridging approach. Not fun when you have many folks working on open files.
Anyway, I'm sure there are implementations where this isn't the case, but just from asking around, the logistical and logical requirement of doubling the ethernet connections is something most people don't think about.
My phone line has rarely gone down if ever. I can't come close to saying that about my internet connections, cable or DSL. The fact that we have two small children means when I pick up that phone in an emergency, I want it to work. I don't want to be mucking around rebooting computers and routers. That's why I've stayed away from VOIP over my existing internet connection.
Any thoughts on the reliability of this? Will VOIP ever be as solid as good old copper? I mean, you have issues (DDOS) with VOIP you just don't have with traditional PSTN service.
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Bah, I can't wait for POWF - Power Over WiFi. Now that would be pretty darn cool!
...this still would have some holes. Is the cable company going to also UPS the distribution point where it splits out? Around KY, the cable goes out before the power (most of the time), so you'd lose your IP over cable, and PoE wouldn't help unless all the communication points were similarly UPS'd.
Tim
Telephones need to work in an emergency including when there is a power failure. Traditional telephones do
The majority of phones today are cordless and practically none work without power.
I used to buy cordless phones that had a speaker on the base unit for this very reason, but alas, those also don't work anymore without power, on most modern phones.
I think you misspelled "minorities"
Depending on the size of the setup, this would likely not hold. With a hosted key solution like Silhouette , every piece of network hardware between your phones and your provider would need to be on a UPS in order for your phones to remain not just powered on, but useful during an power outage. If the call gateway were located inside the office, it too would have pretty hefty power requirements for a UPS along with the network hardware. That being said, it's possible that VoIP could help push Power-over-Ethernet, just by simplifying one of many points of failure during a power outage... and all the Mitel IP phones seem to support PoE.
I'm one of those people who doesn't like cell phones. My land-line is basically already for emergencies only. I'm just as quick to use VoIP as I am the land line.
So I'm one of those people who would gladly ditch the land-line in favor of VoIP once [x] gets improved, where [x] in my case is reliability. VoIP depends on (a) Internet and (b) the power grid, neither of which are near the reliability of POTS.
Even so, I'm still pretty close to ditching the land-line in favor of Vonage. Unfortunately I think it's likely that cell phones will reach POTS price levels before VoIP reaches a POTS level of reliability, so once that happens I may end up going cellular instead of VoIP.
Dlugar
Computer Go: Writing Software to Play the Ancient Game of Go
With the proliferation of cordless telephones in the 80s and 90s, most people today don't even remember that a phone can work without power. And those that do probably don't even have a regular corded phone around the house anymore. I don't think telephone service during a power outage is important to that many people..
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I would love to see a connector that included a substantially gauged section for power, and pins for data.
This way one could plug in any network device with only one connection.
We've been using PoE for IP Telephony rollouts at corporate offices for years, for the exact reasons stated.
I suppose this is driving other uses of it as well, but PoE is neither new, nor unknown. Its just not an OMG kind of technology so it doesn't get a lot of airtime.
Particularly in installations where an existing PBX is being replaced with VoIP technology, its easy and cost effective to attach the call servers and PoE switches to existing UPS setups. Most companies have their IDF on UPS anyways, so it is fairly seamless and provides the same emergency features people have come to expect from PSTN and PBXes.
There are people who don't understand how to correctly wire their stereos, televisions, and VCRs. I would not trust my life in their ability to wire a broadband modem, router, VoIP phone and UPS. I am comfortable relying on the telephone company for 911 service because their CYA department has had years to ensure they will have power when the lights go out.
Are we talking about power over ethernet or power over broadband? If the cable/dsl modem becomes cable/dsl-powered with enough power for all subsequent ethernet connections via power over ethernet, then the 911 system could be expected to work in an idiot-proof fashion.
I'll be your candy shop of infinite deliciousity if you'll be my discotheque of endless rump-shaking.
Am I missing something, or does this not actually make any difference? You'd still have to have a UPS for your hub and your Cable/DSL modem, it just means your IP phone could be somewhere else in the house. Now if we had a PoE connection from the phone company or something, that would be different, but that 100MBps ethernet drop from SBC hasn't been installed yet.
XeoMage
What the hell are you talking about?
The article is discussing power over ethernet, not power over IP.
Dude, seriously, are you high?
-- If I were a fish, I'd be wet
That's obviously what I meant.
The standard seems to be around 220v @ 50 or 60hz AC. I'm not sure I want that kind of load on four twisted pair of cable (CAT5). Besides, being the RJ45 connection could be standard eithernet, what's to prevent your casual user from making a BIG mistake. Jokes aside, it could cause one's battery in a laptop to explode with the force of a stick of TNT.
For power ratings around the world, check out http://kropla.com/electric2.htm
Life is not for the lazy.
Even with PoE a few well placed and clearly marked land lines combined with near ubiquitous cell phones add an extra layer of insurance for 911 and for more mundane VoIP issues.
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Will IP telephones bring in PoE?
I use Comcast's Digital Phone service, and they used to have a box inside the house with a 6 AH gel-cel battery to run it in case of power failure. Well, I moved (only about 10 miles away) last year, and went back to Comcast for my phone service. Now they have a separate infrastucture built out for the phone system with its own power supply (90 VDC on the lines, I was told) so no battery box inside the house. Supposedly it's independent of the lines used for TV and broadband.
The higher the technology, the sharper that two-edged sword.
That is, assuming that people want to use hardware handsets for VoIP.
Next question?
Look at 3Com's NJ200 line.
It replaces a entire wallplate, takes a POE powered backhaul inside the wall, and provides a four-port VLAN-capable (sorta) switch, With POE passthrough on one of the ports, and a couple of keystone blanks for whatever you want.
Umm, why are you rebooting your phones during working hours? That seems like a bad idea.
--
Phil
My refrigerator has Internet, but my ice cream keeps melting.
paintball
PoE (802.3af) is incredibly useful in for business deployments of video cameras and wifi access points, not to mention mini-switches and outdoor wireless bridge equipment. You can even power a laser link with PoE. It makes life easier for those averse to paying out huge amounts of cash to have an electrician come in and put in new outlets. I've been playing with PoE splitters recently to power non PoE gear at 5 & 12V DC - the splitters are $35 ea and are switchable between voltages.
What would happen if I were to, say, plug in my laptop (which is obviously not powered by the CAT5e cable) into a PoE port? Would it have the chance to fry my NIC? I may have to be careful where I stick in my NIC from now on ... either that or follow the experts as use protection, but that's only if the slot's been sleeping around a lot.
Wait. What were we talking about again?
He's just going after the ones who submit GNAA posts.
That's a bad idea, and here's a few reasons why:
#1. WiFi phones are still a ways off, so there are no enterprise level products as of yet.
#2. How do you tell where a call is coming from? An Ethernet jack can be linked to a physical location (i.e. Ethernet Jack 5234-6 is IP address xxx.xxx.xxx.xxx and located on Floor 3 Cube G2-5). It IS possible to triangulate the position of a WiFi phone, but that's done with a large measure of error, and you need good signal strength from more than one AP. There's a reason E911 for cell phones approximates location to a 100-foot radius or so.
#3. WiFI can be jammed. Want to knock out 911 service in a 100-foot radius? Just blast a crapload of power around 2.4 GHz.
Where I work we generally use cisco PoE switches.(3550-SMI-24PWR). Not only do we use them for IP Telephones, but also for our WAPS, which support the 802.3af standard. The WAPs, because they are running cisco's prorietary Discovery Protocol (CDP) are able to regulate how much power (watts) are used by the switchport they are connected to (and obviously by the WAP). This saves a small amount of electricity and is pretty neat.
I would venture guess that most companies which makes switches for the enterprise market will be switching to all poe switches and blades with in the next few years, or atleast make a move too.
Surely wireless power can't be too far off! And we thought our brains were being slightly heated by radio waves...
But only if you have nonzero...ahem...only if you have power and you have ethernet.
All of Nortel's IP phones use PoE and stick to standards such as 802.3af, unlike Cisco.
There are two reasons for this whole process.
The first is the one-wire cost factor you speak of. As opposed to running multiple lines everywhere, you have one ethernet jack- one wire- which will operate a phone. Perfect.
The second, and what was driving it before, always has been wireless. There is not enough power over IP to operate modern equipment. The idea is mainly access points. I can run one ethernet wire to an area a couple feet from the ceiling in the hallway of a hotel or office. I don't need to also get an electrician to run a plug there. Suddenly I can put my access points in places without power- outside, on ceilings, brought up through floors, etc. where power is not conventionally found.
Run one cable to each access point, plug it in, and it works.
when you see the word 'Linux', drink!
We have an extremely large VoIP installation with all of our phones PoE... one thing we found out early on is that just about every PoE capable switch we looked at could not provide enough power to run all ports supporting Class III devices. A 48 port switch realistically could only support 30 or so devices, and that was with some super new higher wattage power supplies. That made our finance people see red as we kept asking for more and more PoE switches, and having to tell them that 18 ports per switch are unusable...
Smart way to link to your own website with the UPS link.
Not that there's anything wrong with that!
The filesystem is the package manager
Now call me crazy... but here is my concern... if you have been around working on computers for individuals for very long you know that the phone lines are the #1 source of power surges. Now with that said... aren't we just adding more fuel to the fire by putting a power inlet there? I mean... if lightning hits... it not only would take out your phones thru the data/voice segments.. but also spike along the power lines blowing regulators and caps all over... PoE or not they still have to isolate the circuit to protect it and what happens is the surge protector takes the hit.. and needs replaced.. guess what... not as easy as just plugging in the ol' tele...
Now with that said I use wireless for my Internet Access (yes not dsl nor cable but wireless 802.11b connection to a couple of shared T1's (hey only thing I can get here) with this setup I use PoE and I use it alot.. I have several routers all around the neighbor hood to share the connection all over with and they all go over PoE.
Umm, why are you rebooting your phones during working hours? That seems like a bad idea.
Couple reasons...one, it's a relatively new technology and sometimes the phones reboot themselves. This has gotten rarer as the implementation has progressed, but it seems a bit odd to put that many points of failure out there when it affects completely unrelated functional systems.
Also, we are not the typical 9-5 shop. There are people working from 7 to midnight, and much of that is very important financial production work. Sure, they can tweak the phone system during the remaining hours, but this is difficult...again...particularly during early implementation when lots of tweaking takes place.
My point is that before combining the two worlds, a messed up phone system is a messed up phone system. Now that has the capacity to whack the PCs and the network too.
Not to mention the fact that it makes network guys phone guys--as if they don't already have enough to do.
IP phones will only do so if there is an uninterrupted power supply (UPS). The only practical way of guaranteeing power supply to a large number of IP phones is PoE.'
Because POE doesn't require an UPS during a power failure? The Ethernet just keeps on working without power? And the power keeps working because the ethernet is working, right?
Or.... you have a big honkin' UPS in the basement that powers the ethernet and the POE?
Modern FTTP installations require a significant battery to keep your fiber-transported dialtone working during an outage. Now you add some central UPS to keep you IP telephony working? At some point, don't you just start outfitting houses with battery arrays and generators?
So you take the industrial solution already used by the telco and put it in a small package for the individual home.
Which would be what you've got with POTS- they keep these huge-assed banks of batteries at the CO to power the landline phones for days without AC power to run them. They tried to accomplish this with ADSL services so they could make that leap without major re-work (I know, they attempted to make a low enough power consumption single chip solution at TI- they never could quite make it...)- the problem is that ADSL speeds weren't enough and they couldn't do the power thing (the chip drew about 100-200ma too much from what I understand...) so they went ahead with fiber and are putting the batteries out at the premises. PoE's kind of silly, when you think about it- how is the signal getting into the neighborhood? Fiber. How is fiber going to carry power with the levels of optical and electrical tech we have these days? Now, if they could have made the leap with the copper loops with something like Ethernet over phone lines (which they have, but it doesn't work in all locations because of what they've done over the years to the loops...) they probably could have managed the jump with no probs. In fact, I'm surprised they went the fiber route- it's not much better than the long-haul Ethernet over POTS loops, but it doesn't give them the ability to meet the emergency services requirements.
I am not merely a "consumer" or a "taxpayer". I am a Citizen of the State of Texas
I wanted to make sure that the phones stayed up at all times, so I bout a decent UPS for the wiring/server rack, installed netgear POE switches ($119 for 4port POE, 4port non-POE) and connected up all of the IP phones (polycom IP-500 and sipura 841). Since the cost of the POE switch was so low, I decided to do it this way for the comfort of being able to dial 911 at any time in any room.
Yes, it is overkill for the home, but I like it and my phones have stayed up all of the time. Several of the offices I work for use centrex and there phones are plugged into normal power. They have had several outages since the installations 3-4 months ago.
--Keith
Now that's thinking.
...[bland music]... CLICK... "Thank you for molding! While you are becoming lichen, we are wallowing in protopasm. But rest assured, our staphlococci think your cholera is very important. Please continue to mold." CLICK... [bland music]...
A thousand cell phones with a thousand batteries costs how much, and performs how well, compared to PoE phones? The tower, the switch, whatever, there's a bottleneck somewhere. In a major emergency [earthquake] it will ALL go down anyway.
All pass beyond reach of medicine. None pass beyond the reach of love.
Why bother to do power over Ethernet when you can make tesla's dream come true and do power over thin air. Just do wireless power and all of you can stop bitching, wired this and ups that..blah blah blah.
My ISP (Charter) offers a $40/mo phone connection. Why is it worth more than Vonage's $25/mo service? According to the phone rep , because it includes a UPS so it works when the power goes out. Must be a heck of a UPS for $15/mo.
Memex?
Get your Unix fortune now!
Setup one of these instead.
Midnight Special
Change the Wifi from <1 watt to >1000 watt. Now that would be HOT, and still cool to the touch. And you will have plenty of power. Go ahead and set up anything in the beam.
Sometimes POE does simplify things, but wireless access points can be powered by wall-warts just fine, and they're reliable as long as the rest of your building has power. (And if your building loses electricity for very long, most of your computers will die, though laptops get you an hour or two of extra time if you don't mind working in the dark.)
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
My part of town has the utilities buried, and doesn't have much of a flooding problem except when street construction crews do stupid things. But we still have momentary power outages 4-5 times a year, and occasionally have longer outages every year or two. The phones are a bit more reliable, but they've still gone down.
Cell phones make a fine backup - and it wouldn't be that hard for somebody to make a VOIP box with fallback cellphone service and a battery good for an hour of talk time, without the same size and weight constraints as a portable phone.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
That would be a bad thing if they required it. But typical businesses have a PBX or key system that also needs power. VOIP phones without POE mean there's another thing to plug in at your desk besides your computer, and if you don't have a built-in UPS (like the one in your cellphone), then the phone won't work if the power's down, but in a typical office building you're not going to get much work done in the dark with your computer down. So you can use your cell phone while you walk outside with your coworkers.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
We used to have broadband over ethernet, power over power lines.
Now we have power over ethernet and broadband over power lines.
There are other codecs that start with a higher sample rate, typically 11kHz or 22kHz (natural for Soundblaster-like PC sound cards) and compresses them. Skype uses some codecs from Global IP Sound, and I think that's one of the options they're using. There are other ways to get higher-than-telco fidelity - 7KHz audio with 48kbps ADPCM was an old standard that had better sound than PCM but still used very low CPU horsepower (the ADPCM codecs are simple adaptive compressors that model the sound waveform, as opposed to the complex perceptual modeling tricks used in tighter codecs.)
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
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Is this assumption that our power supply cannot be hardened in the same way as the Telco system thus making this whole discussion moot since power would then be just as reliable as telephone service. And before you say cost I have to call bull shit. Every major metro area buries its plumbing and those systems of tunnles are more than large enough and comprehensive enough to run wires everywhere that power runs above ground now.
Also if you do large underground connecting tunnles you introduce the possibility of just being precise about it and enabling laser power transmission systems. Or perhaps beaming microwaves down a metal pipe. Wonder if that would work ? After all the metal walls of a microwave contain the emmissions of the magnetron, not abosrb it. Imagine its efficiency would have something to do with the absobtion of power by the air in the tunnel unless you created a vacume....
Hmm science experiment... a metal tube a few cm in diameter (large enough to contain the wave), with a magnetron at one end and a 2.4ghz antenna at another attached to a multimeter to measure power transmission efficiency. The recieving antenna would have be capable of absorbing as much energy was was being out put... otherwise you would probably harm the magnetron.
I don't ask you to be me. I only ask you not expect me to be you.
Does a phone with a backup battery count?
Of course a UPS is required for VOIP to work in an emergency. But then I don't know anyone who is enough of a geed to get VOIP who doesn't have their computers protected by UPS anyways.
I don't think this is sufficient motivational force. With cell phone penetration into the market, it's more likely that someone will already have a cell phone than a UPS power supply on their computers. Considering that cell phones already have an E911 requirement with GPS location transmission with the E911 call, the point is moot.
Given another decade plus, land based phones will be something reserved for call centers, office complexes, and a minority of the world population.
My phone, PDA and MP3 player all recharge from USB...
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Just to think... Most of my secondary systems are only connected to power and network... How cool would it be to connect them to only one cable, while the main system has over 30? Seems rather amusing...
We run the Cisco IP Phones (like the ones in 24 and every other TV show and movie lately).
About half the switches in our company inject power... one small catch is if you disconnect the phone and plug something else in too quickly... I find most standard NICs don't like 48 volts running through them.
We have had them for years (since early 2001 I think) and over the years we have lost power several times. Bit of a pain but we have our own gateway to POTS both at our head office as well as one of our branch offices overseas so if the internet drops out the phones still work.
This may have been already covered, but can anyone explain to me why it's called "Power over Ethernet" when - to me at least - it should be called "Power over Cat-5"? The power delivery has nothing what-so-ever to do with Ethernet, has it? Can you run token-ring over Cat-5? If so, in that case could you have "Power over token-ring" or PoTR?? :)
Internet over telephone lines (dialup/DSL).
Telephony via the internet (VOIP).
Internet via Cable.
TV via internet.
Internet via wireless.
Internet radio.
IP via Avian protocol (see the RFC).
Birds on the internet (will not provide any links).
Internet via power lines.
Power to the People, via the web (Power to the People).
${YEAR+1} is going to be the year of Linux on the desktop!
BTW, suck my cock!
How about power over fiber? :-)
The only way I would see to get it to work would be to come up with a new jack for the connection. That would render millions of existing ethernet jacks obsolete. This could be like trying to get the USA to switch from Standard to Metric again. The only difference is that it would be on a global scale. Europe would want to have their standard (read France), then there would be the correct US standard, then others like China and Tiawan. Then it would get political. About a year later we would find out that Amazon has a patent on it somehow.
The phone company (the one that powers traditional phones) certainly isn't going to provide POE lines, which means you need a POE capable switch ... that plugs into the wall. D'oh! Not much good in a (power loss type) emergency.
I have been a network infrastructure engineer for the past six years, working for professional services companies that are Cisco resellers. PoE was news about four years ago, and I cannot think of a single customer of ours in the last two years that has not looked at including PoE in orders for new switches. And of them, the vast majority have included it, even for deals where they were not looking to install IPT right away.
I am not saying it is everywhere, but to say that IPT will make PoE big is false. IPT has already made PoE big.
PoE has tremendous value, especially when you're installing equipment in difficult locations. It wouldn't surprise me if the electrician's union reps got wind of this and sent their thugs out to do some re-education. "We can't have no non-union IT guys installin' power over *any* wires, cuz that's a union job. Got it?" Yes, they still have thugs.
... eh, don't get me started. Suffice it to say that "I don't like USB."
PoE should have killed off USB. I hate the fact that the USB connector doesn't have a positive locking mechanism. The RJ-45 is amazingly well designed from a connector perspective - cheap, easy to use, reliable as all hell. I understand that one of USB's aims was to be "painless for the used to install," which is a noble goal. However, the protocol stack and other cruft associated with it makes it expensive to implement in embedded systems (where most of the target devices live.) I'd much rather have PoE with a proper network protocol than USB and it's
This article and many of the replies seem to confuse residential vs. business phone service. When one makes the statement "traditional phones never go out when the power goes out," what they really mean is that residential phones don't go out because they're powered by the central office and business phones don't go out because the company's PBX is on a UPS/backup generator. The article seems to address business uses of VOIP, describing routers & switches that are POE enabled (provided by a UPS in the event of a power failure.) But what about home use? A major issue regarding VOIP is 911 service during power failures. Just where is the power going to come from for POE in the home? The cable modem? The home router? Magic? This bring us back to having to have a UPS to keep the equipment up during a power failure? So what's the point?
I visited an AT&T long distance center in California some years back. They had a room full of lead-acid cells ready to keep everything up.
The lesson here is: have a system that isn't dependant on the power company.
The clearance system sounds logical. It is not. It is completely arbitrary. -- John Bolton
Does'nt power over ethernet require a pair from the 8 wires in order to work? If so..that would conflict with Gigabit over Ethernet which uses all 8 wires in a cat5/6 cable.
You can't do POE with 1000TX though.
d igest09186a0080091a86.html
http://www.cisco.com/en/US/tech/tk389/tk214/tech_
So, there is that downside.
Casca
It's too bad that they didn't sieze the opportinity to use a new connector that doesn't have the disadvantages of the current acrylic modular connector. It would be great to have a robust retention mechanism that can't break of snag (yes I know there are some snag free designs out there). It would also be nice to have a non-proprietary weatherproof version.
I am becoming gerund, destroyer of verbs.
Back in the late 90s cell phones ceased to be a status symbol of the self-important. Today they are cheaper than land lines (and that is before you add in things like voicemail that are extra on the land line) for many people, and just work. Today the cell phone is just a different phone, one that you have with you when you want it. It isn't about me anymore, it is about getting things done that need the phone, no matter where I am.
I give my cell phone out to anyone who might want to call me. When I don't want to talk I look at the caller-id (included) and then hit cancel.
I just switched my Verizon landline to SunRocket. $16.58 a month ($199 a year), all those bells and whistles included, and no extra fees, monthly or otherwise. Plus, cancel any time and get the unused months fully refunded. Also, a free 2-handset cordless phone. And E911. And $3 of international calling and two directory services calls per month included in that price. And a second incoming number free.
Isn't USB just SCSI commands over a different physical transport?
There: Something at a specific location.
Their: Owned by someone.
Please make sure your english compiles.