I was happy to see this article paid some attention to the technical hurdles - namely interference - that BPL poses. Though I'm a little upset to see in
the article that, "experts say these issues have been worked out and that interference is no longer a problem." This is simply not true. I'd love to know
who their experts are.
As a radio hobbyist and
student in electrical engineering, I feel this potential is really more of a certainty - its fundamental to
the technology. It's not just a little kink to be worked out.
That said, I certainly see nothing wrong with broadband over power lines (BPL) being given a chance
to succeed or fail on its own merits, under sensible and objective oversight by the Federal
Communications Commission. Unfortunately, the Commission is falling down on the job.
The FCC has allowed BPL to operate under Part 15 of the FCC rules. These are the rules you often see
printed on the back of remote controls, calculators or digital alarm clocks. They say simply that the
device can't be used if it causes interference, and that it is afforded no protection from interference
from other devices.
The big difference between an alarm clock and BPL should be pretty obvious. Small electronics are
very low power, localized, and operate intermittently. Most of them shouldn't be emitting radio waves
at all. BPL, on the other hand, works by injecting a strong radio signal into power lines (read:
antennas). It operates over a wide area, with high power, 24 hours a day. Part 15 was never designed to
deal with a system like this. Cable TV, for example, is governed by a very strict and specific set of
regulations to ensure non-interference.
For Part 15 to work, there really needs to be a pretty reasonable expectation that devices don't pose any
real risk before they're released into the wild. Such an expectation might be established through field
tests or studies. Several such studies have been conducted, but since the outcomes weren't too
favorable, the Commission has largely ignored them, and has contented itself by simply amending Part
15 to require that BPL operators have the capability to apply "mitigation techniques" to reduce, but not
eliminate, interference after the fact.
But if those don't provide an adequate solution, then what? I don't think for a second that a BPL
provider, with millions of dollars riding on its service, will just shut down its operations as the rules
would seem to require. More likely, responses would range somewhere from outright denial of the
problem, to definitional arguments over what constitutes "harmful interference." Such arguments could
drag on for years. In fact, this is already happening in Manassas, VA and has been for some time.
This sort of deploy first, clean up the mess later strategy is a ridiculous way to allow an industry to
operate. The rationalization seems to be that BPL is just too "exciting" a technology to be hindered
with the gravity of sound technical analysis, and that it must be deployed even if it means
compromising the Commission's obligation to protect licensed spectrum users from interference. But
an effective Commission can't let catchy marketing monopolize its judgment.
It's also because he almost always throws in a couple of fanatical anti-Microsoft rants.
Yes... this is called pandering. He does that because he thinks it makes him look "cool" in the eyes of the community he wishes to attract. If you read many of his anti-Microsoft rants (along with most everything he ever writes) you will discover that many of the statements he makes don't actually make sense.
I couldn't have said it better myself.
Really, don't you think the fact that he has to tell you "why you should pay attention to him" is enough evidence of this by itself? Most people who I pay attention to don't need to remind me why. I pay attention to them because they have accomplishments to their name which demonstrate that their words are worth something.
My HDTV set has a DVI input, I would assume that your expensive plasma TV does also. Just plug in your plasma TV to a computer with a DVI output capable of displaying a full resulution picture for your screen (1920x1080 for 1080i, though DVDs are only 480p). Plug that computer into your network, and you're golden. It should be the same quality as if you were playing from a normal DVD player (which can also be found in varieties with a DVI out).
If your set doesn't have a DVI input (so sad) you ought to be able to get an adapter that will give you a component video signal from your computer to put into the TV.
There should be no loss of quality over a DVD player.
It's too bad the the requirement is down to 5wpm now.
Mod this down.
Can't you find someplace else to whine about the reduction of the code requirement? You've got a right to your opinion, but this really isn't the place for it. I'm tired of seeing every forum discussion having anything remotely to do with ham radio devolve into a code vs. no-code debate. It's happened! Can't we just move on? (For the non-hams out there, if you could harness the energy dissapated by all the flames in all the flamewars on this topic, the resulting fireball would make the sun look like a cigarette butt).
Watching folks opreate code who are very skilled is indeed impressive. There are still lots of ham operators who enjoy using morse code on it's own merits. It will live on, required or not.
A properly set up station does not pose a health risk, even at 10 or 1000 watts of power.
BPL is not a health risk, I'm not sure why the original poster added that in. BPL is, however, a very real interference problem.
I agree that MPE limits and RF burns should not be a problem. I'm not sure where the original poster got that from - I also don't see it on the ARRL site.
HOWEVER, the interference concern is VERY real. 250mW can go a long way - I'm not sure where you get your "few hundred meters" figure from. I know people who operate "QRP", a low-power mode, who regularly use similar power levels to talk to ham operators hundreds of miles away!
Let's not forget, a "transmission line" at 60 Hz is much more like an ANTENNA at HF! Powerlines will radiate VERY well.
What's so different about the interference from BPL is that its broadband - that is to say the signal is several tens of MHz wide, spanning all of the HF bands. A spur from another local noise source or unlicensed device is less of a problem because you can simply use another frequency - with BPL this is not possible.
Make no mistake, BPL poses a real problem to HF communication.
I'm not quite so ready to believe the health-realated concerns, but the interference problems that will result from an implementation of BPL are very real. I've seen a demonstration of BPL's interference at a local hamfest here in the Washington, DC area (For those interested, AMRAD will also be giving a presentation at the DC area Winterfest hamfest in February). BPL makes a lot of noise on an HF receiver, across the entire tuning range! But what is potentially even worse is that a relatively small amount of power (I believe they gave the example of 10 watts into a dipole at reasonable proximity) is enough to cause a link to fail.
Undoubtedly, a ham radio operator's neighbors, and perhaps the power company, will put a lot of pressure on him to cease operating a ham radio. This is totally backwards! Let's revisit the Part 15 rules for a minute - the regulations that apply to unlicensed services, including BPL. It says that an unlicensed device MAY NOT cause harmful interference to a licensed service but an unlicensed device must accept any harmful interference received.
This basically means that the burden for resolving any interference problem is on the head of the unlicensed service, in this case, the power company - at least in theory. I have a hard time believing it will play out this way though. In fact, when the FCC asked for comments on a notice of inquiry with regards to relaxing part 15 standards, many power companies claimed that NO INTERFERENCE PROBLEM EXISTS, and it is up to other users to PROOVE it, before they should be required to act on it. This is a total reversal of the roles established by Part 15! And that is leaving aside the fact that there are several studies done by hams, including a very good one from AMRAD, that do proove, both empiracally and mathematically, the interference threat. BPL promoters, including the heads at the FCC, have turned a blind eye.
HF radio is used to provide long-distance communications during disasters by many groups, including ham radio organizations, and FEMA. (FEMA has recently weighed in on the debate) It also carries shortwave broadcast from other countries, which would be sqaushed by interference.
It does not make sense that the FCC should allow an unlicensed user to render this huge chunk of spectrum totally useless to it's intended users. It's selfish and shortsighted.
Please write your congressperson. Make them aware of the problems BPL could bring.
After a bit of thought, I've decided that if I wrote pieces for my 12th grade english class like Robert X. Cringely writes his columns, I'd receive terrible grades.
Why? His writing never supports its claims with actual evidence beyone the anecdotal. You can't base a business plan off of an afternoon daydream, just the same way you can't "bounce" a Wi-Fi signal over a mountain with a +15dBm power level (see links).
The point is, Cringely may have some interesting ideas, but he fails to back them up or do any sort of research to try to ascertain their feasibility in the real world, other than spouting off a few random statistics. You'd think Robert might wish to find others that support his opinions. Surely if his ideas are so wonderful, others in the know would validate them. Perhaps talking to an executive from a "failed" Wi-Fi company might have been appropriate for this article.
Cringely may think he knows everything, see his about page on his website. "On Why You Should Pay Attention to Him: When it comes to information technology, I know what I am talking about. Twenty years in and around the PC business have earned me wisdom, if not wealth." As most of us know, a thousand years in the tech industry won't earn you wisdom, and some of the wisest people are those who realize that they don't know everything.
My question is, "Why does Cringely get paid to write his columns?" Week after week of faulty analysis doesn't seem like it makes Cringely a very good columnist. PBS needs to wise up.
Globalising companies are not expanding to the third world to "send much needed money into the country". They are looking to exploit the quality-of-life and legislative differential between 1st and 3rd world countries. Corporations don't like anti-exploitation, safety laws, environmental protection laws -- it cuts potential profits.
Corporations only exist and only work towards making a profit for their owners. That is all they do. Ethics do not come into it.
It's quite naive of anyone to make the suggestion that corporations go into other countries out of charity, and I don't think this is what your parent was suggesting. As you say, they do it to better their business. This is what companies do in capitalism, if they don't cut costs to increase profit, a competitor will, and the company will die.
So maybe companies are greedy and go to third world countries for the wrong reasons. It really doesn't matter. It still gets "much needed money" to the place it needs to go. Albeit for very selfish motives - but mutual self-interest is the force that drives capitalism.
Note that I say "mutual" self-interest. If poor countries and poor people in those countries did not also stand to benefit, they simply wouldn't take part in our globalization system. Why would they?
The standard of living does not go down because of foreign investment. Globalization does not make the poor poorer.
Foreign investment is the ONLY way that poor countries will ever become more wealthy. There is no other place for wealth to come from other than from the places it already exists.
I've never liked Robert Cringley's style or manner, which basic can be summed up as observing the obvious, then claiming all the credit or screaming "SCANDAL" where there really is none. But what made me really dislike him forever is his total lack of journalistic ethics a.k.a. MAKING SHIT UP.
He has a history of INVENTING stories that simply do not exist. IMHO he should meet the same fate as Jayson Blair. I do not know why PBS hasn't caught on.
No, it simply would not work. It is very difficult to bounce a rather narrowband morse code signal off of the moon, with incredibly large directional antennas and very high power. Due to many of the problems on that page which you link to, it would simply destroy a wideband data signal like 802.11, which is between 10 and 20MHz wide!
This simply cannot work, for a multitude of reasons.
Assuming the network actually could be constructed, the number of hops to get from one place to another would be enourmous. Latency would be incredible, and routing would be a nightmare. How would a packet know where to go?
Not to mention that 802.11 is a half-duplex system. It uses one frequency at a time, and cannot listen and receive simultaneously.
Ponder this for a moment:
A--------B----------C
Station B is inbetween stations A and C. A and C cannot hear each other, but B can hear each one, and is supposed to provide a means for A and C to communicate.
A starts transmitting and B listens. Meanwhile, C cannot hear A and ALSO starts transmitting at the same time.
The result: Packet collision city.
This will not yield reliable communication, espescially when the whopping megabit of actual bandwidth is filled up.
With more than 3 nodes, the situation will get even worse.
802.11 was simply not designed with anything remotely like this in mind.
Using several wireless radios at each node and careful planning, it might be possible to establish a long-distance network (though I highly doubt country wide).
But the organization and planning necessary would be far beyond the reach of a volunteer effort like this one.
I have also noticed the suggestiong of using 802.11 under FCC Part 47 (amateur radio license). Running high-powered 802.11 is not as easy as getting a ham license. You have to find or build rather a expensive microwave amplifier, and over a certain power level, you must automatically control power. Not to mention that under part 47, you may not use encryption, which is a serious drawback.
Bouncing off the moon (as suggested somewhere on this page) will _NOT_ work! Earth-Moon-Earth is possible -- with narrow band morse code and huge amounts of power. Still, it is barely distinguishable from noise. There is not a chance in hell that a wideband signal like 802.11 could even come close to surviving the journey to the moon and back.
I think this effort would have a much better chance of succeeding if it was directed in the direction of developing new hardware that is fit for this task.
802.11 will not be able to do the job. It is simply impossible.
-Ben
I wonder why this is so important. Whats it doing on slashdot? Somebody came out with a somewhat un-exciting open source project, and they used the GPL in a questionable manner. What else is new?
Slashdot Mirror
I was happy to see this article paid some attention to the technical hurdles - namely interference - that BPL poses. Though I'm a little upset to see in the article that, "experts say these issues have been worked out and that interference is no longer a problem." This is simply not true. I'd love to know who their experts are.
As a radio hobbyist and student in electrical engineering, I feel this potential is really more of a certainty - its fundamental to the technology. It's not just a little kink to be worked out. That said, I certainly see nothing wrong with broadband over power lines (BPL) being given a chance to succeed or fail on its own merits, under sensible and objective oversight by the Federal Communications Commission. Unfortunately, the Commission is falling down on the job. The FCC has allowed BPL to operate under Part 15 of the FCC rules. These are the rules you often see printed on the back of remote controls, calculators or digital alarm clocks. They say simply that the device can't be used if it causes interference, and that it is afforded no protection from interference from other devices.
The big difference between an alarm clock and BPL should be pretty obvious. Small electronics are very low power, localized, and operate intermittently. Most of them shouldn't be emitting radio waves at all. BPL, on the other hand, works by injecting a strong radio signal into power lines (read: antennas). It operates over a wide area, with high power, 24 hours a day. Part 15 was never designed to deal with a system like this. Cable TV, for example, is governed by a very strict and specific set of regulations to ensure non-interference.
For Part 15 to work, there really needs to be a pretty reasonable expectation that devices don't pose any real risk before they're released into the wild. Such an expectation might be established through field tests or studies. Several such studies have been conducted, but since the outcomes weren't too favorable, the Commission has largely ignored them, and has contented itself by simply amending Part 15 to require that BPL operators have the capability to apply "mitigation techniques" to reduce, but not eliminate, interference after the fact.
But if those don't provide an adequate solution, then what? I don't think for a second that a BPL provider, with millions of dollars riding on its service, will just shut down its operations as the rules would seem to require. More likely, responses would range somewhere from outright denial of the problem, to definitional arguments over what constitutes "harmful interference." Such arguments could drag on for years. In fact, this is already happening in Manassas, VA and has been for some time.
This sort of deploy first, clean up the mess later strategy is a ridiculous way to allow an industry to operate. The rationalization seems to be that BPL is just too "exciting" a technology to be hindered with the gravity of sound technical analysis, and that it must be deployed even if it means compromising the Commission's obligation to protect licensed spectrum users from interference. But an effective Commission can't let catchy marketing monopolize its judgment.
It's also because he almost always throws in a couple of fanatical anti-Microsoft rants. Yes ... this is called pandering. He does that because he thinks it makes him look "cool" in the eyes of the community he wishes to attract. If you read many of his anti-Microsoft rants (along with most everything he ever writes) you will discover that many of the statements he makes don't actually make sense.
I couldn't have said it better myself. Really, don't you think the fact that he has to tell you "why you should pay attention to him" is enough evidence of this by itself? Most people who I pay attention to don't need to remind me why. I pay attention to them because they have accomplishments to their name which demonstrate that their words are worth something.
Amen. Mind you this is what Cringely does for EVERYTHING.
My HDTV set has a DVI input, I would assume that your expensive plasma TV does also. Just plug in your plasma TV to a computer with a DVI output capable of displaying a full resulution picture for your screen (1920x1080 for 1080i, though DVDs are only 480p). Plug that computer into your network, and you're golden. It should be the same quality as if you were playing from a normal DVD player (which can also be found in varieties with a DVI out).
If your set doesn't have a DVI input (so sad) you ought to be able to get an adapter that will give you a component video signal from your computer to put into the TV.
There should be no loss of quality over a DVD player.
-Ben
Mod this down.
Can't you find someplace else to whine about the reduction of the code requirement? You've got a right to your opinion, but this really isn't the place for it. I'm tired of seeing every forum discussion having anything remotely to do with ham radio devolve into a code vs. no-code debate. It's happened! Can't we just move on? (For the non-hams out there, if you could harness the energy dissapated by all the flames in all the flamewars on this topic, the resulting fireball would make the sun look like a cigarette butt).
Watching folks opreate code who are very skilled is indeed impressive. There are still lots of ham operators who enjoy using morse code on it's own merits. It will live on, required or not.
Ben Gelb, KF4KJQ
A properly set up station does not pose a health risk, even at 10 or 1000 watts of power. BPL is not a health risk, I'm not sure why the original poster added that in. BPL is, however, a very real interference problem.
...and scale. A single house running BPL is a lot different than an entire neighborhood or city, which would cause widespread interference.
I agree that MPE limits and RF burns should not be a problem. I'm not sure where the original poster got that from - I also don't see it on the ARRL site.
HOWEVER, the interference concern is VERY real. 250mW can go a long way - I'm not sure where you get your "few hundred meters" figure from. I know people who operate "QRP", a low-power mode, who regularly use similar power levels to talk to ham operators hundreds of miles away!
Let's not forget, a "transmission line" at 60 Hz is much more like an ANTENNA at HF! Powerlines will radiate VERY well.
What's so different about the interference from BPL is that its broadband - that is to say the signal is several tens of MHz wide, spanning all of the HF bands. A spur from another local noise source or unlicensed device is less of a problem because you can simply use another frequency - with BPL this is not possible.
Make no mistake, BPL poses a real problem to HF communication.
I'm not quite so ready to believe the health-realated concerns, but the interference problems that will result from an implementation of BPL are very real. I've seen a demonstration of BPL's interference at a local hamfest here in the Washington, DC area (For those interested, AMRAD will also be giving a presentation at the DC area Winterfest hamfest in February). BPL makes a lot of noise on an HF receiver, across the entire tuning range! But what is potentially even worse is that a relatively small amount of power (I believe they gave the example of 10 watts into a dipole at reasonable proximity) is enough to cause a link to fail.
Undoubtedly, a ham radio operator's neighbors, and perhaps the power company, will put a lot of pressure on him to cease operating a ham radio. This is totally backwards! Let's revisit the Part 15 rules for a minute - the regulations that apply to unlicensed services, including BPL. It says that an unlicensed device MAY NOT cause harmful interference to a licensed service but an unlicensed device must accept any harmful interference received.
This basically means that the burden for resolving any interference problem is on the head of the unlicensed service, in this case, the power company - at least in theory. I have a hard time believing it will play out this way though. In fact, when the FCC asked for comments on a notice of inquiry with regards to relaxing part 15 standards, many power companies claimed that NO INTERFERENCE PROBLEM EXISTS, and it is up to other users to PROOVE it, before they should be required to act on it. This is a total reversal of the roles established by Part 15! And that is leaving aside the fact that there are several studies done by hams, including a very good one from AMRAD, that do proove, both empiracally and mathematically, the interference threat. BPL promoters, including the heads at the FCC, have turned a blind eye.
HF radio is used to provide long-distance communications during disasters by many groups, including ham radio organizations, and FEMA. (FEMA has recently weighed in on the debate) It also carries shortwave broadcast from other countries, which would be sqaushed by interference.
It does not make sense that the FCC should allow an unlicensed user to render this huge chunk of spectrum totally useless to it's intended users. It's selfish and shortsighted.
Please write your congressperson. Make them aware of the problems BPL could bring.
After a bit of thought, I've decided that if I wrote pieces for my 12th grade english class like Robert X. Cringely writes his columns, I'd receive terrible grades.
Why? His writing never supports its claims with actual evidence beyone the anecdotal. You can't base a business plan off of an afternoon daydream, just the same way you can't "bounce" a Wi-Fi signal over a mountain with a +15dBm power level (see links).
http://www.pbs.org/cringely/pulpit/pulpit20020207. html
http://www.oreillynet.com/pub/wlg/1124
The point is, Cringely may have some interesting ideas, but he fails to back them up or do any sort of research to try to ascertain their feasibility in the real world, other than spouting off a few random statistics. You'd think Robert might wish to find others that support his opinions. Surely if his ideas are so wonderful, others in the know would validate them. Perhaps talking to an executive from a "failed" Wi-Fi company might have been appropriate for this article.
Cringely may think he knows everything, see his about page on his website. "On Why You Should Pay Attention to Him: When it comes to information technology, I know what I am talking about. Twenty years in and around the PC business have earned me wisdom, if not wealth." As most of us know, a thousand years in the tech industry won't earn you wisdom, and some of the wisest people are those who realize that they don't know everything.
My question is, "Why does Cringely get paid to write his columns?" Week after week of faulty analysis doesn't seem like it makes Cringely a very good columnist. PBS needs to wise up.
It's quite naive of anyone to make the suggestion that corporations go into other countries out of charity, and I don't think this is what your parent was suggesting. As you say, they do it to better their business. This is what companies do in capitalism, if they don't cut costs to increase profit, a competitor will, and the company will die.
So maybe companies are greedy and go to third world countries for the wrong reasons. It really doesn't matter. It still gets "much needed money" to the place it needs to go. Albeit for very selfish motives - but mutual self-interest is the force that drives capitalism.
Note that I say "mutual" self-interest. If poor countries and poor people in those countries did not also stand to benefit, they simply wouldn't take part in our globalization system. Why would they?
The standard of living does not go down because of foreign investment. Globalization does not make the poor poorer.
Foreign investment is the ONLY way that poor countries will ever become more wealthy. There is no other place for wealth to come from other than from the places it already exists.
I've never liked Robert Cringley's style or manner, which basic can be summed up as observing the obvious, then claiming all the credit or screaming "SCANDAL" where there really is none. But what made me really dislike him forever is his total lack of journalistic ethics a.k.a. MAKING SHIT UP.
He has a history of INVENTING stories that simply do not exist. IMHO he should meet the same fate as Jayson Blair. I do not know why PBS hasn't caught on.
A prime example is his incredible story of bouncing a Wi-Fi signal over a mountain, which can be found at http://www.pbs.org/cringely/pulpit/pulpit20020207. html.
Most of his Wi-Fi tall tales are at least physically possible, but this one crosses the line.
See Rob Flickenger's Response.
No, it simply would not work. It is very difficult to bounce a rather narrowband morse code signal off of the moon, with incredibly large directional antennas and very high power. Due to many of the problems on that page which you link to, it would simply destroy a wideband data signal like 802.11, which is between 10 and 20MHz wide!
This simply cannot work, for a multitude of reasons. Assuming the network actually could be constructed, the number of hops to get from one place to another would be enourmous. Latency would be incredible, and routing would be a nightmare. How would a packet know where to go? Not to mention that 802.11 is a half-duplex system. It uses one frequency at a time, and cannot listen and receive simultaneously. Ponder this for a moment: A--------B----------C Station B is inbetween stations A and C. A and C cannot hear each other, but B can hear each one, and is supposed to provide a means for A and C to communicate. A starts transmitting and B listens. Meanwhile, C cannot hear A and ALSO starts transmitting at the same time. The result: Packet collision city. This will not yield reliable communication, espescially when the whopping megabit of actual bandwidth is filled up. With more than 3 nodes, the situation will get even worse. 802.11 was simply not designed with anything remotely like this in mind. Using several wireless radios at each node and careful planning, it might be possible to establish a long-distance network (though I highly doubt country wide). But the organization and planning necessary would be far beyond the reach of a volunteer effort like this one. I have also noticed the suggestiong of using 802.11 under FCC Part 47 (amateur radio license). Running high-powered 802.11 is not as easy as getting a ham license. You have to find or build rather a expensive microwave amplifier, and over a certain power level, you must automatically control power. Not to mention that under part 47, you may not use encryption, which is a serious drawback. Bouncing off the moon (as suggested somewhere on this page) will _NOT_ work! Earth-Moon-Earth is possible -- with narrow band morse code and huge amounts of power. Still, it is barely distinguishable from noise. There is not a chance in hell that a wideband signal like 802.11 could even come close to surviving the journey to the moon and back. I think this effort would have a much better chance of succeeding if it was directed in the direction of developing new hardware that is fit for this task. 802.11 will not be able to do the job. It is simply impossible. -Ben
I wonder why this is so important. Whats it doing on slashdot? Somebody came out with a somewhat un-exciting open source project, and they used the GPL in a questionable manner. What else is new?