Spam filters like Spamassassin actually work remarkably well. Why? Because spam recipients, by definition, are unwilling. The users, filter maintainers, blacklist operators, ISPs and sometimes even the government are all willing to cooperate to a common goal.
It's an entirely different story when you have two resourceful parties who want to communicate and will deploy all sorts of resourceful defenses and countermeasures -- starting with end-to-end encryption -- to ensure that they can continue to communicate. Stopping spam is absolutely trivial by comparison.
It's not that difficult to exchange symmetrical keys using an asymmetrical encryption method.
Indeed. When I read the documents on the passive optical splitters that AT&T installed for the NSA, it became utterly obvious to me that those of us who developed the present generation of Internet encryption protocols in the 1990s (and I'm one of them) made a big mistake. We were too concerned about major-league threats like active man-in-the-middle attacks and not concerned enough about simple, transparent and totally automatic encryption that would still be 100% effective
against passive eavesdropping. Our existing crypto protocols generally require a heavy-duty public-key infrastructure and administrator or user action to
generate those keys and get them signed. Most people don't bother, so they just operate in the clear. Had we standardized a simple unkeyed Diffie-Hellman exchange as the starting default
with signatures as an option, we could have stopped this kind of massive dragnet eavesdropping in its tracks.
I still think one of the most brilliant developments in practical cryptography was SSH. The idea of simply caching the public key on the first connection and checking to see if it has
changed on later connections is vulnerable to a man-in-the-middle attack on that very first connection, but it still solves 99% of the problem with 1% of the effort. That's
the proper model for any new effort to routinely encrypt everything, all the time, to make the haystacks as big as we can.
Why write low-strength encryption software when high-strength software already exists and is plenty fast? Why do people just assume that high-strength cryptography has to be unacceptably slow?
For years I've routinely encrypted as much of my communications as I can (e.g., when I control both ends of the connection) and the overhead is completely invisible.
I think even most delusional people can readily tell the difference between make-believe violence and real-world violence. I'm just not that concerned about violent video games, movies or TV programs. I indulge in them myself on occasion. But I am concerned about the local and national news because its major theme is
real-world violence, where real people really suffer, die and do not respawn in just a few seconds.
The local news always leads off with a sensational report on some horrible crime in the area, and the national news always reports on the
latest suicide bombing in Iraq and the steady stream of dead and maimed soldiers. We Americans have made it clear that we
see large scale, organized violence (i.e., war) or the threat of same to be our preferred solution to nearly every
problem we face in the world. When, invariably, we kill innocent people, our generals shrug their shoulders and "regret"
the "collateral damage". They always blame it on the other side, claiming "they made us do it".
And then everybody is stunned, shocked and surprised when an individual in the US does the same thing on a much smaller scale. The VPI shooting was basically a slow-motion suicide bombing. As horrible as it was, the same thing happens almost
daily in Iraq, killing about the same number of people. And why? Because some guy has serious psychological problems, a sociopathic
personality and an almost
complete lack of empathy for other human beings. The only difference is that one of them was elected to office, and because of
the power we continue to let him have,
many more people have died and continue to die as a result than died in Blacksburg a few days ago.
Thanks for the correction. I'm not a biologist, but I read a lot of literature from the evolution wars so it certainly seemed like the terms macroevolution and microevolution were pure creationist inventions because their bogus definitions were the only ones I'd see.
The creationists' definition of "microevolution" is "evolution that's so obvious that even we cannot deny it", while "macroevolution" is "evolution that we pretend
doesn't exist because it bothers us on theological, political or dogmatic grounds".
Even the scientific use of those two terms seems rather imprecise, but that's to be expected since, as you say, there is no biological barrier between them.
Not only is the distinction between "microevolution" and "macroevolution" entirely artificial, but those terms are entirely creationist in origin. They have no scientific meaning.
In mainstream biology there is only one form of evolution. Mainstream biologists never the terms "microevolution" and "macroevolution" except to refute the creationists in their own language.
Creationists devised those terms in a desperate attempt to reconcile the overwhelming empirical evidence for evolution with religious dogma claiming that God created all the various "kinds" of plants and animals in their present forms. ("Kinds" is another purely biblical term that has no use in mainstream biology.) Creationists could no longer deny clear examples of evolution such as the development of bacterial antibiotic resistance or human sickle-cell trait (an evolutionary adaptation to malaria), so they try to pretend that these constitute a "micro" form of evolution that is somehow fundamentally different from the way that evolution produces new species ("macroevolution").
Evolution is a slow process that has acted on earth for billions of years. The evolutionary changes one can see during the span
of a single human lifetime are necessarily small, but they are no different in principle from the much larger changes that occur over much longer periods of time. In other words, "macroevolution" is nothing more than "microevolution" plus long periods of time, and the
creationists cannot plausibly argue otherwise.
Yes, I also noticed the apparent collision between the 2nd stage engine bell and the interstage fairing at separation, and I'm surprised there has been zero mention of this in the media.
It's common to see engine nozzles glowing like this, although I am also wondering about the irregular pattern.
I can't find a definitive statement on SpaceX's website, but it appears from a drawing that they use regenerative cooling of the second stage nozzle. So one theory that occurs to me is that collision damage to the nozzle could have caused a leak and a roll moment that either grew too big for the roll thrusters to correct or ran them out of propellant gas early.
Video from other upper stages, such as Delta, show very stable systems. You can hardly tell that the video is playing except by the clouds moving slowly by underneath. Falcon 1's upper stage flight was very different. There was a lot of attitude noise throughout the burn, culminating in an undamped nutating or coning motion toward the end of flight, and then a slow roll to the left. None of this could have been normal.I can think of several other possible failure mechanisms: a combustion instability; numerical instability in the guidance system; fuel sloshing in the tank; and fuel swirling as it flows into the engine, imparting a roll moment.
I was about to make the same suggestion -- ask your neighbors to use wireless only for laptops. I'm surprised
at how many desktop systems use 802.11 when they could be plugged in almost as easily. Wires are faster, too.
I regularly plug in my laptop when I have a lot of stuff to transfer, such as a full backup. Gigabit Ethernet still beats any form of 802.11.
It may seem counterintuitive, but one good way to reduce your interference to your neighbors' WiFi networks is to put more access
points in your own house.
This is especially true if you can't cover your whole house with a single access point. Above all, resist the antisocial temptation to get a power amplifier. Use the cellular approach instead.
Get more access points, spread them across channels 1, 6 and 11 and sprinkle them around your house. Set them all to the same ESSID and plug them into an Ethernet switch (if the access points have built-in routers, use no more than one so all the access points will be on the same logical Ethernet segment.) Your laptop will automatically hand off to the nearest access point when you move, just like a cell phone.
Even if you can cover your whole house with a single access point, having several reduces your average radio link distance and lets the links operate
at a higher average speed. (802.11g runs from 1 megabit/sec up to 54 megabits/sec, depending on signal-to-noise ratio). Most WiFi transmitters run at constant power, so increasing your average data rate reduces your transmission time and the interfering energy you dump onto your neighbors for each megabyte of data you transfer.
Oh, sure, you can double the bandwidth over cable with QAM, but do you have to? You bet.
Would it not have been better to have a single tuner standard, with a single encoding standard, and a single resolution standard? No.
Modems are cheap compared to the channels over which they operate. Nowadays they're mostly software. Using the wrong type of modem can squander much of a channel's capacity. So why not have several, one for each type of channel you use? As long as they're selected automatically, what do you care?
And don't even think of arguing VSB or QAM. As a consumer, I don't give a shit which has more technical superiority in certain circumstances - I want it to work. VSB and QAM don't even compete with each other, so there's no debate. 8-VSB is used over the air while the various flavors of QAM (64-QAM, 128-QAM, 256-QAM) are used over cable. 8-VSB
is specifically designed to resist noise, both digital and analog co-channel interference, multipath and selective fading. This robustness comes at the
expense of data rate. 8-VSB over the standard US 6 MHz TV channel provides 19.39 Mb/s.
US cable systems also use 6 MHz channels, so 8-VSB would certainly work over cable too.
But it would waste cable capacity because the cable channel is so much cleaner than the broadcast channel.
256-QAM, popular on US cable systems, provides about 38 Mb/s per 6 MHz channel, about twice that of 8-VSB in the same bandwidth.
This signal is necessarily more 'fragile' than 8-VSB, but it works fine on a well-engineered hybrid fiber/coax system.
Perhaps you meant to compare 8-VSB to DVB/OFDM, the over-the-air scheme used in Europe and other countries? This is where the debate has raged. OFDM, with its built-in
multipath resistance, had a definite advantage over 8-VSB in early implementations. But as the receive equalizers in 8-VSB improved, it has become at least the equal of OFDM according to the on-air tests I've seen. Both work.
Many digital TVs sold in the support both ATSC 8-VSB and QAM signals. 8-VSB is obviously needed for over-the-air reception, but you can't necessarily receive digital TV from
your cable system even if you have a QAM tuner. My experience with Time Warner Cable is that all of the digital TV channels are encrypted except for the minority taken from local TV
broadcast stations. In other words, with just a QAM tuner in your set you can't get anything from cable that you can't get from an antenna. This makes the QAM tuner much less
useful than it could be.
Some (but not many) digital TVs have slots for a "CableCard". You rent this from your local cable company, and it decrypts the remaining digital channels for you (or at least the ones
to which you have subscribed). Besides not being available yet on most digital TVs, current CableCards are unable to handle two-way services such as video-on-demand and pay-per-view,
so it's just not very useful yet. That means you might as well rent a digital tuner box from your cable company and plug it into your TV set with HDMI so that you don't use
the TV's QAM tuner at all.
Your argument, like Utah's is patently silly. Cell companies Leases the airwaves, investors put billions into towers and infrastructure and networks and storefronts, an you imply ALL OF THAT should be done for FREE because we already "OWN" the airwaves? Your argument is the silly one, even though it's made all too frequently.
Nobody is saying that cellular service should be free. It cost money to build the infrastructure, and of course the carrier should be able to get a return (and a profit) on that.
What people are saying is that they should not be allowed to abuse their monopoly (or near-monopoly) position in one market by wielding it as a club against competition
in another market. (Here, it's using their market power in wide area wireless digital access to block competition in the POTS "call termination" market.)
It's especially problematic when the government created the monopoly and sold it to them in the first place.
This is what the antitrust laws are all about. They may be out of favor with the current (rather radical) government, but they've been around for over a century and are hardly an unproven (or "socialistic") concept. In fact, the antitrust laws, on the relatively few occasions they've been honestly enforced, have generally proven to be a win for everybody.
It's a common myth that solar power can only work in the sunny Southwest. Arizona (the sunniest part of the US) has only twice as much
annual sunlight as Alaska (the least). Electric rates around the US vary much more than 2:1, and wind power is even more variable.
Other important factors are state and local subsidies and tax treatments, and above all, state net metering laws. Hydrogen is a remarkably costly and inefficient
way to transmit or even to store electricity. It makes far more sense to pump surplus solar electricity back into the grid and draw it back at night
or in the winter. That's what I do here in California, where we have net metering with an annual "true up".
The utilities aren't ecstatic about it, but they still come out ahead because I generate most of my surplus on sunny summer afternoons when electricity is especially valuable. The increasing use
of time-of-use meters and real-time pricing will also boost the economics of rooftop solar with net metering.
Note that the web page mentioned here was written by (or under the direction of) Senator James Inhofe (R-OK), the former chairman of
the Senate Environment and Public Works Committee. After the Senate changed hands, he is now its ranking minority member.
Inhofe is famous (infamous) for his extreme political conservatism, bordering on theocracy. He said that the 9/11 attacks were a form of "divine retribution" on the
US for failing to defend Israel, and he voted against the McCain amendment banning torture. Despite no scientific training, he consistently characterizes global warming as a "massive hoax".
Naturally, Inhofe's political views are not a reason to summarily dismiss his statements here out of hand, but people should 1) know his background 2) fact-check everything he says and 3) read a summary of the evidence and a range of views on global warming, especially the scientific consensus, before deciding what
weight to give Inhofe's remarks. Even the rapidly dwindling band of global warming skeptics within the scientific community have distanced themselves from Inhofe's statements.
50 years? Try 141 years! The Kasson Metric Act of 1866 (that's the year eighteen sixty six) legalized the metric system in the United States and established an official conversion table. It specifically stated that no contract or law shall be deemed invalid because of the use of metric units.
See http://lamar.colostate.edu/~hillger/laws/metric-ac t.html.
Power-factor-corrected power supplies are actually slightly less efficient than uncorrected supplies. However, those small losses
are worth it to avoid the losses and other problems caused by harmonic currents flowing in the grid.
Large industrial users are charged extra for poor power factor, but residential users are not. So without EU-style regulations, there hasn't been much of a market draw in the US for PF-corrected supplies.
Incorrect. Most electronic power supplies, at least those sold in the USA, have terrible power factors. This includes the computers and compact fluorescents that now dominate many office environments. While they are not inductive loads, their current waveforms are highly distorted. The typical switching power supply that directly rectifies and filters the AC input has a power factor of 0.59. Since PF = Watts/VA, just multiplying volts times amps gives a power figure that's 70% larger than the real value.
These power supplies inject so much harmonic power back into the line that they've actually started fires in older commercial buildings. Until recently, the code allowed the neutral in 3-phase 4-wire wye branch circuits to be smaller than the phase conductors. This was okay before compact fluorescents and personal computers, but their harmonic currents add in the neutrals of such circuits and can overload it.
I've heard that the European Union, unlike the US, mandates power factor correction for electronic power supplies. Unfortunately those devices haven't made it to the US in large quantities despite a global market.
Actually, it is. Before QoS, routers handled all packets in neutral, FIFO order. QoS, by its very nature, handles packets in something other
than FIFO order. With QoS, some kinds of packets are more important than others.
But there's nothing wrong with QoS per se.
The real issue is who controls the QoS rules? The users or the carriers?
As far as I'm concerned, I pay for my DSL line so I should get to decide which
packets on it are more important than others.
Yes, I understand that I also use shared facilities beyond the end of my DSL line. But QoS is relevant only where there's a bottleneck, and in practice my access link is almost always the bottleneck.
I think the debate over network neutrality would be a lot more productive if it could be directed away from whether all packets are equal (they aren't) and toward who
gets to decide which packets are more important than others. I'm astounded that nobody seems to realize this.
I use Linux on my upstream DSL link (I have no control over the downstream link, but the uplink link is much slower). I give top priority to VoIP, bottom priority to Bit Torrent, and intermediate priority to everything else.
Within each traffic class, fair queuing ensures that each stream gets its fair share. Before QoS, VoIP was useless whenever I ran
Bit Torrent. With QoS, I can run as many BT sessions as I want with no effect on VoIP at all, and even my interactive sessions are much more usable. I consider QoS a dramatic improvement,
but only because I got to decide the policy, not my ISP.
Having said all this, I think it reasonable for carriers to set policies and mechanisms to keep a few customers from hogging shared transmission facilities at the expense of everyone else. It's even reasonable to give a bigger capacity share to customers who pay more. But it is definitely not reasonable for them to decide which of my applications or remote peers are or aren't important. That's entirely my business.
A large part of the problem can be blamed on Congress and the 1996 Communications Act. It was a serious mistake to discard over a century of experience reigning in
monopoly abuses with antitrust law and common
carrier regulation. Monopolists have always promised us the moon if they can just keep and expand their monopolies, but they never seem to deliver.
While there is pretty healthy competition in long-haul transmission, local transmission is still a de-facto monopoly (or at best a duopoly) nearly everywhere and it should be regulated as such. The wires and fibers in the streets should be available at reasonable, tariffed rates to any service provider willing to pay for them. Their owners would be
barred from selling bundled Internet services, so they would not be able to drive the independents out of business (as the telcos drove out most of the DSL providers),
nor could they discriminate among user applications. The unregulated service providers could
discriminate, but because they'd be in an open, competitive market I would always have the option of switching to another provider if one got too far out of line.
Another way to accomplish the same ends without a major political sea change would be for municipalities to install their own transmission facilities, again
leasing them out to service providers just as they build and maintain roads used by commercial transportation services. Is it any surprise that the monopolists are trying their damndest to outlaw this?
It all depends on where you are. First, your electric rates are extraordinarily low. San Diego residential rates are on the order of 14 cents/kWh, and they increase with increasing consumption. Second, available wind energy varies enormously with location. Both factors strongly affect the economic viability of grid-tied wind generation.
Wind energy is far more dependent on location than solar energy. The available annual solar energy in the desert Southwest is only about twice that in Alaska. This means that the geographic variation in electric rates has a greater effect on the viability of a solar electricity system than annual sunlight. But the wind energy available in mountainous areas of the US like the Rockies is more than ten times that available in the Southeast. That's why you see big clusters of windmills in mountain passes and other windy areas, and few if any in typical suburbs.
Also note that your average wind speed does not tell you what you need to know. Available power from the wind goes up as the cube of wind speed, so bursts of strong wind produce more energy than steady light breezes.
So the bottom line is that unless you live in a very windy area, your electric rates are already so low that no form of home power
generation is likely to be very cost-effective for you right now. So you have to ask yourself two questions: what you think will happen to your electric rates in the future, and whether solar might make more sense than wind in your area.
Why does everyone just know that fiber to the home is too expensive? My house already has an electric power line, a gas line, a water pipe,
a sewer pipe, telephone lines and a cable TV feed, and installing all those services didn't break the bank. Fiber is now cheap enough that labor
dominates the installation costs, so why not just install it and be done with it? Especially since it can obviate both telephone twisted pair and cable TV coax as it finally brings fast Internet connectivity?
But no. Instead, we're stuck with (at best) ISDN, DSL and cable modems, kludges designed to run over wires originally designed for entirely different
purposes. As if the endless hype about broadband over power line -- an even worse kludge that will make collateral damage of the HF radio spectrum -- isn't bad enough, now we have hype about broadband over natural gas lines. What's next? When will the energy utilities realize that their main assets aren't their existing wires and
pipes, it's their rights of way. If they were smart, they'd install fiber to leapfrog over the telcos and cablecos and clean up in the local communications market. But no.....!
I run my own personal incoming mail servers. They get a lot of spam, but Spamassassin is so amazingly effective I don't have to be annoyed by most of it. Spam uses a small fraction of my DSL link capacity, so that doesn't bother me either.
My MX server advertises STARTTLS, so a fair bit of my incoming mail, and much of my spam, is automatically encrypted on the way. Not most of it, but enough to create a steady stream of "opaque chaff" from exotic locations all over the planet. And that just might make it a *leetle* bit harder for the NSA's traffic analyzers vacuuming up all my packets through their illegal fiber taps at the major switching centers.
Okay, then go ahead and dump your garbage and sewage in the street. Why pay for garbage hauling and sewer services when they don't benefit you?
Obviously anybody who actually pays for those services is an economic imbecile, or at least a misguided altruist.
You asked about battery performance at cold temperatures. I found data for the popular 18650 Li-ion cell widely used in laptops
and camcorders (and now the Tesla Roadster). The specified discharge temperature range is -20C to +60C. At -20C it is supposed to have >= 60% of
its capacity at +20C. That's not quite the -25F you mentioned, but with the heat remaining from charging (and I^2R losses from discharging) I think
it should still do pretty well.
Don't you guys have block heaters up there? Even gasoline cars don't do well at these low temps, and you could use those electrical
outlets year round for more than just heat.
Slashdot Mirror
It's an entirely different story when you have two resourceful parties who want to communicate and will deploy all sorts of resourceful defenses and countermeasures -- starting with end-to-end encryption -- to ensure that they can continue to communicate. Stopping spam is absolutely trivial by comparison.
I still think one of the most brilliant developments in practical cryptography was SSH. The idea of simply caching the public key on the first connection and checking to see if it has changed on later connections is vulnerable to a man-in-the-middle attack on that very first connection, but it still solves 99% of the problem with 1% of the effort. That's the proper model for any new effort to routinely encrypt everything, all the time, to make the haystacks as big as we can.
For years I've routinely encrypted as much of my communications as I can (e.g., when I control both ends of the connection) and the overhead is completely invisible.
The local news always leads off with a sensational report on some horrible crime in the area, and the national news always reports on the latest suicide bombing in Iraq and the steady stream of dead and maimed soldiers. We Americans have made it clear that we see large scale, organized violence (i.e., war) or the threat of same to be our preferred solution to nearly every problem we face in the world. When, invariably, we kill innocent people, our generals shrug their shoulders and "regret" the "collateral damage". They always blame it on the other side, claiming "they made us do it".
And then everybody is stunned, shocked and surprised when an individual in the US does the same thing on a much smaller scale. The VPI shooting was basically a slow-motion suicide bombing. As horrible as it was, the same thing happens almost daily in Iraq, killing about the same number of people. And why? Because some guy has serious psychological problems, a sociopathic personality and an almost complete lack of empathy for other human beings. The only difference is that one of them was elected to office, and because of the power we continue to let him have, many more people have died and continue to die as a result than died in Blacksburg a few days ago.
And how well does this work if people encrypt their files and send the keys separately?
The creationists' definition of "microevolution" is "evolution that's so obvious that even we cannot deny it", while "macroevolution" is "evolution that we pretend doesn't exist because it bothers us on theological, political or dogmatic grounds".
Even the scientific use of those two terms seems rather imprecise, but that's to be expected since, as you say, there is no biological barrier between them.
In mainstream biology there is only one form of evolution. Mainstream biologists never the terms "microevolution" and "macroevolution" except to refute the creationists in their own language.
Creationists devised those terms in a desperate attempt to reconcile the overwhelming empirical evidence for evolution with religious dogma claiming that God created all the various "kinds" of plants and animals in their present forms. ("Kinds" is another purely biblical term that has no use in mainstream biology.) Creationists could no longer deny clear examples of evolution such as the development of bacterial antibiotic resistance or human sickle-cell trait (an evolutionary adaptation to malaria), so they try to pretend that these constitute a "micro" form of evolution that is somehow fundamentally different from the way that evolution produces new species ("macroevolution").
Evolution is a slow process that has acted on earth for billions of years. The evolutionary changes one can see during the span of a single human lifetime are necessarily small, but they are no different in principle from the much larger changes that occur over much longer periods of time. In other words, "macroevolution" is nothing more than "microevolution" plus long periods of time, and the creationists cannot plausibly argue otherwise.
And steam isn't corrosive?
It's common to see engine nozzles glowing like this, although I am also wondering about the irregular pattern.
I can't find a definitive statement on SpaceX's website, but it appears from a drawing that they use regenerative cooling of the second stage nozzle. So one theory that occurs to me is that collision damage to the nozzle could have caused a leak and a roll moment that either grew too big for the roll thrusters to correct or ran them out of propellant gas early.
Video from other upper stages, such as Delta, show very stable systems. You can hardly tell that the video is playing except by the clouds moving slowly by underneath. Falcon 1's upper stage flight was very different. There was a lot of attitude noise throughout the burn, culminating in an undamped nutating or coning motion toward the end of flight, and then a slow roll to the left. None of this could have been normal.I can think of several other possible failure mechanisms: a combustion instability; numerical instability in the guidance system; fuel sloshing in the tank; and fuel swirling as it flows into the engine, imparting a roll moment.
I regularly plug in my laptop when I have a lot of stuff to transfer, such as a full backup. Gigabit Ethernet still beats any form of 802.11.
It may seem counterintuitive, but one good way to reduce your interference to your neighbors' WiFi networks is to put more access points in your own house. This is especially true if you can't cover your whole house with a single access point. Above all, resist the antisocial temptation to get a power amplifier. Use the cellular approach instead.
Get more access points, spread them across channels 1, 6 and 11 and sprinkle them around your house. Set them all to the same ESSID and plug them into an Ethernet switch (if the access points have built-in routers, use no more than one so all the access points will be on the same logical Ethernet segment.) Your laptop will automatically hand off to the nearest access point when you move, just like a cell phone.
Even if you can cover your whole house with a single access point, having several reduces your average radio link distance and lets the links operate at a higher average speed. (802.11g runs from 1 megabit/sec up to 54 megabits/sec, depending on signal-to-noise ratio). Most WiFi transmitters run at constant power, so increasing your average data rate reduces your transmission time and the interfering energy you dump onto your neighbors for each megabyte of data you transfer.
Modems are cheap compared to the channels over which they operate. Nowadays they're mostly software. Using the wrong type of modem can squander much of a channel's capacity. So why not have several, one for each type of channel you use? As long as they're selected automatically, what do you care?
US cable systems also use 6 MHz channels, so 8-VSB would certainly work over cable too. But it would waste cable capacity because the cable channel is so much cleaner than the broadcast channel. 256-QAM, popular on US cable systems, provides about 38 Mb/s per 6 MHz channel, about twice that of 8-VSB in the same bandwidth. This signal is necessarily more 'fragile' than 8-VSB, but it works fine on a well-engineered hybrid fiber/coax system.
Perhaps you meant to compare 8-VSB to DVB/OFDM, the over-the-air scheme used in Europe and other countries? This is where the debate has raged. OFDM, with its built-in multipath resistance, had a definite advantage over 8-VSB in early implementations. But as the receive equalizers in 8-VSB improved, it has become at least the equal of OFDM according to the on-air tests I've seen. Both work.
Many digital TVs sold in the support both ATSC 8-VSB and QAM signals. 8-VSB is obviously needed for over-the-air reception, but you can't necessarily receive digital TV from your cable system even if you have a QAM tuner. My experience with Time Warner Cable is that all of the digital TV channels are encrypted except for the minority taken from local TV broadcast stations. In other words, with just a QAM tuner in your set you can't get anything from cable that you can't get from an antenna. This makes the QAM tuner much less useful than it could be.
Some (but not many) digital TVs have slots for a "CableCard". You rent this from your local cable company, and it decrypts the remaining digital channels for you (or at least the ones to which you have subscribed). Besides not being available yet on most digital TVs, current CableCards are unable to handle two-way services such as video-on-demand and pay-per-view, so it's just not very useful yet. That means you might as well rent a digital tuner box from your cable company and plug it into your TV set with HDMI so that you don't use the TV's QAM tuner at all.
Nobody is saying that cellular service should be free. It cost money to build the infrastructure, and of course the carrier should be able to get a return (and a profit) on that.
What people are saying is that they should not be allowed to abuse their monopoly (or near-monopoly) position in one market by wielding it as a club against competition in another market. (Here, it's using their market power in wide area wireless digital access to block competition in the POTS "call termination" market.)
It's especially problematic when the government created the monopoly and sold it to them in the first place.
This is what the antitrust laws are all about. They may be out of favor with the current (rather radical) government, but they've been around for over a century and are hardly an unproven (or "socialistic") concept. In fact, the antitrust laws, on the relatively few occasions they've been honestly enforced, have generally proven to be a win for everybody.
Other important factors are state and local subsidies and tax treatments, and above all, state net metering laws. Hydrogen is a remarkably costly and inefficient way to transmit or even to store electricity. It makes far more sense to pump surplus solar electricity back into the grid and draw it back at night or in the winter. That's what I do here in California, where we have net metering with an annual "true up".
The utilities aren't ecstatic about it, but they still come out ahead because I generate most of my surplus on sunny summer afternoons when electricity is especially valuable. The increasing use of time-of-use meters and real-time pricing will also boost the economics of rooftop solar with net metering.
Inhofe is famous (infamous) for his extreme political conservatism, bordering on theocracy. He said that the 9/11 attacks were a form of "divine retribution" on the US for failing to defend Israel, and he voted against the McCain amendment banning torture. Despite no scientific training, he consistently characterizes global warming as a "massive hoax".
Naturally, Inhofe's political views are not a reason to summarily dismiss his statements here out of hand, but people should 1) know his background 2) fact-check everything he says and 3) read a summary of the evidence and a range of views on global warming, especially the scientific consensus, before deciding what weight to give Inhofe's remarks. Even the rapidly dwindling band of global warming skeptics within the scientific community have distanced themselves from Inhofe's statements.
50 years? Try 141 years! The Kasson Metric Act of 1866 (that's the year eighteen sixty six) legalized the metric system in the United States and established an official conversion table. It specifically stated that no contract or law shall be deemed invalid because of the use of metric units. See http://lamar.colostate.edu/~hillger/laws/metric-ac t.html.
Large industrial users are charged extra for poor power factor, but residential users are not. So without EU-style regulations, there hasn't been much of a market draw in the US for PF-corrected supplies.
These power supplies inject so much harmonic power back into the line that they've actually started fires in older commercial buildings. Until recently, the code allowed the neutral in 3-phase 4-wire wye branch circuits to be smaller than the phase conductors. This was okay before compact fluorescents and personal computers, but their harmonic currents add in the neutrals of such circuits and can overload it.
I've heard that the European Union, unlike the US, mandates power factor correction for electronic power supplies. Unfortunately those devices haven't made it to the US in large quantities despite a global market.
Actually, it is. Before QoS, routers handled all packets in neutral, FIFO order. QoS, by its very nature, handles packets in something other than FIFO order. With QoS, some kinds of packets are more important than others.
But there's nothing wrong with QoS per se. The real issue is who controls the QoS rules? The users or the carriers?
As far as I'm concerned, I pay for my DSL line so I should get to decide which packets on it are more important than others.
Yes, I understand that I also use shared facilities beyond the end of my DSL line. But QoS is relevant only where there's a bottleneck, and in practice my access link is almost always the bottleneck.
I think the debate over network neutrality would be a lot more productive if it could be directed away from whether all packets are equal (they aren't) and toward who gets to decide which packets are more important than others. I'm astounded that nobody seems to realize this.
I use Linux on my upstream DSL link (I have no control over the downstream link, but the uplink link is much slower). I give top priority to VoIP, bottom priority to Bit Torrent, and intermediate priority to everything else. Within each traffic class, fair queuing ensures that each stream gets its fair share. Before QoS, VoIP was useless whenever I ran Bit Torrent. With QoS, I can run as many BT sessions as I want with no effect on VoIP at all, and even my interactive sessions are much more usable. I consider QoS a dramatic improvement, but only because I got to decide the policy, not my ISP.
Having said all this, I think it reasonable for carriers to set policies and mechanisms to keep a few customers from hogging shared transmission facilities at the expense of everyone else. It's even reasonable to give a bigger capacity share to customers who pay more. But it is definitely not reasonable for them to decide which of my applications or remote peers are or aren't important. That's entirely my business.
A large part of the problem can be blamed on Congress and the 1996 Communications Act. It was a serious mistake to discard over a century of experience reigning in monopoly abuses with antitrust law and common carrier regulation. Monopolists have always promised us the moon if they can just keep and expand their monopolies, but they never seem to deliver.
While there is pretty healthy competition in long-haul transmission, local transmission is still a de-facto monopoly (or at best a duopoly) nearly everywhere and it should be regulated as such. The wires and fibers in the streets should be available at reasonable, tariffed rates to any service provider willing to pay for them. Their owners would be barred from selling bundled Internet services, so they would not be able to drive the independents out of business (as the telcos drove out most of the DSL providers), nor could they discriminate among user applications. The unregulated service providers could discriminate, but because they'd be in an open, competitive market I would always have the option of switching to another provider if one got too far out of line.
Another way to accomplish the same ends without a major political sea change would be for municipalities to install their own transmission facilities, again leasing them out to service providers just as they build and maintain roads used by commercial transportation services. Is it any surprise that the monopolists are trying their damndest to outlaw this?
Wind energy is far more dependent on location than solar energy. The available annual solar energy in the desert Southwest is only about twice that in Alaska. This means that the geographic variation in electric rates has a greater effect on the viability of a solar electricity system than annual sunlight. But the wind energy available in mountainous areas of the US like the Rockies is more than ten times that available in the Southeast. That's why you see big clusters of windmills in mountain passes and other windy areas, and few if any in typical suburbs.
Also note that your average wind speed does not tell you what you need to know. Available power from the wind goes up as the cube of wind speed, so bursts of strong wind produce more energy than steady light breezes.
So the bottom line is that unless you live in a very windy area, your electric rates are already so low that no form of home power generation is likely to be very cost-effective for you right now. So you have to ask yourself two questions: what you think will happen to your electric rates in the future, and whether solar might make more sense than wind in your area.
All this information is readily available; the Wikipedia article on wind power is as good a place to start as any.
Why does everyone just know that fiber to the home is too expensive? My house already has an electric power line, a gas line, a water pipe, a sewer pipe, telephone lines and a cable TV feed, and installing all those services didn't break the bank. Fiber is now cheap enough that labor dominates the installation costs, so why not just install it and be done with it? Especially since it can obviate both telephone twisted pair and cable TV coax as it finally brings fast Internet connectivity?
But no. Instead, we're stuck with (at best) ISDN, DSL and cable modems, kludges designed to run over wires originally designed for entirely different purposes. As if the endless hype about broadband over power line -- an even worse kludge that will make collateral damage of the HF radio spectrum -- isn't bad enough, now we have hype about broadband over natural gas lines. What's next? When will the energy utilities realize that their main assets aren't their existing wires and pipes, it's their rights of way. If they were smart, they'd install fiber to leapfrog over the telcos and cablecos and clean up in the local communications market. But no.....!
My MX server advertises STARTTLS, so a fair bit of my incoming mail, and much of my spam, is automatically encrypted on the way. Not most of it, but enough to create a steady stream of "opaque chaff" from exotic locations all over the planet. And that just might make it a *leetle* bit harder for the NSA's traffic analyzers vacuuming up all my packets through their illegal fiber taps at the major switching centers.
Whatever you say. When somebody resorts to ad-hominem attacks, I know I've won the argument.
Okay, then go ahead and dump your garbage and sewage in the street. Why pay for garbage hauling and sewer services when they don't benefit you? Obviously anybody who actually pays for those services is an economic imbecile, or at least a misguided altruist.
Don't you guys have block heaters up there? Even gasoline cars don't do well at these low temps, and you could use those electrical outlets year round for more than just heat.