brad's blog

RV daisy chain power grid

After every RV trip (I'm back from Burning Man) I think of more I want RVs to do. This year, as we have for many years, we built a power distribution system with a master generator rather than having each RV run its own noisy, smelly and inefficient generator. However, this is expensive and a lot of work for a small group, it is cheap and a lot of work for a larger group.

There's been a revolution in small generator design of late thanks to the declining cost of inverters and other power conversion. A modern quality generator feeds the output of its windings to circuits to step up and step down the voltage to produce the required power. The output power is cleaner and more stable, and the generator is spun at different RPMs based on the power load, making it quieter and more efficient. With many models, you can also combine the internal output of two generators to produce a higher power generator.

RVs have come with expensive old-style generators that are quieter than cheap ones, and which produce better power, but today they are moving to inverter generators. With an inverter generator, it's also possible to draw on the RV batteries for power surges (such as starting an AC or microwave) beyond what the generator can do.

I'm interested in the potential for smarter power, so what I would like to see is a way for a group of RVs with new generation power systems to plug together. In this way, they could all make use of the power in the other vehicles, and in most cases only a fraction of the generators would need to be running to provide power to all. (For example, at night, only one generator could power a whole cluster. In the day, with ACs running, several would need to run, but it would be very unlikely to have to run all, or even 75% of them.)

RV water tank should have UV disinfector

RVs all have a fresh water tank. When you rent one, they will often tell you not to drink that water. That's because the tanks are being filled up in all sorts of random places, out of the control of the rental company, and while it's probably safe, they don't want to promise it, nor disinfect the tank every rental.

I recently got a small "pen" which you put in a cup of water and it shines a UV light for 30 seconds to kill any nasties in the water. While I have not tried to test it on infected water, I presume that it works.

On worldcon and convention design

The Worldcon (World Science Fiction Convention) in Montreal was enjoyable. Like all worldcons, which are run by fans rather than professional convention staff, it had its issues, but nothing too drastic. Our worst experience actually came from the Delta hotel, which I'll describe below.

For the past few decades, Worldcons have been held in convention centers. They attract from 4,000 to 7,000 people and are generally felt to not fit in any ordinary hotel outside Las Vegas. (They don't go to Las Vegas both because there is no large fan base there to run it, and the Las Vegas Hotels, unlike those in most towns, have no incentive to offer a cut-rate deal on a summer weekend.)

Because they are always held where deals are to be had on hotels and convention space, it is not uncommon for them to get the entire convention center or a large portion of it. This turns out to be a temptation which most cons succumb to, but should not. The Montreal convention was huge and cavernous. It had little of the intimacy a mostly social event should have. Use of the entire convention center meant long walks and robbed the convention of a social center -- a single place through which you could expect people to flow, so you would see your friends, join up for hallway conversations and gather people to go for meals.

This is one of those cases where less can be more. You should not take more space than you need. The convention should be as initimate as it can be without becoming crowded. That may mean deliberately not taking function space.

A social center is vital to a good convention. Unfortunately when there are hotels in multiple directions from the convention center so that people use different exits, it is hard for the crowd to figure one out. At the Montreal convention (Anticipation) the closest thing to such a center was near the registration desk, but it never really worked. At other conventions, anywhere on the path to the primary entrance works. Sometimes it is the lobby and bar of the HQ hotel, but this was not the case here.

When the social center will not be obvious, the convention should try to find the best one, and put up a sign saying it is the congregation point. In some convention centers, meeting rooms will be on a different floor from other function space, and so it may be necessary to have two meeting points, one for in-between sessions, and the other for general time.

The social center/meeting point is the one thing it can make sense to use some space on. Expect a good fraction of the con to congregate there in break times. Let them form groups of conversation (there should be sound absorbing walls) but still be able to see and find other people in the space.

A good thing to make a meeting point work is to put up the schedule there, ideally in a dynamic way. This can be computer screens showing the titles of the upcoming sessions, or even human changed cards saying this. Anticipation used a giant schedule on the wall, which is also OK. The other methods allow descriptions to go up with the names. Anticipation did a roundly disliked "pocket" program printed on tabloid sized paper, with two pages usually needed to cover a whole day. Nobody had a pocket it could fit in. In addition, there were many changes to the schedule and the online version was not updated. Again, this is a volunteer effort, so I expect some glitches like this to happen, they are par for the course.

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Photos should be tagged for alternate aspect ratios

Today, fewer and fewer photos are printed. We usually see them on screen. And more and more commonly, we see them on a widescreen monitor. 16:9 screens are quite common as are 16:10. You can hardly find a 4:3 screen any more, though that is the aspect ratio of most P&S cameras. Most SLRs are 3:2, which still doesn't fit on the widescreen monitor.

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In Montreal for Worldcon

I'm in Montreal for the next 5 days for the World Science Fiction convention. I already did 3 panels on Thursday, one more on Nanotech to do on Sunday. Great crowd of people here. Then it's back to Burning Man preparation. Due to an error we got terrible placement in the city this year but I'm working on it.

Shortly I will post new thoughts on the nature of consciousness I had after talking to Peter Watts. Watts is the author of the novel Blindsight which I highly recommend.

Amazing eclipse at Enewetak, Marshall Islands

The total eclipse of the sun is the most visually stunning natural phenomenon there is. It leaves the other natural wonders like the Grand Canyon far behind. Through an amazing set of circumstances I got to see my 4th on Enewetak, an isolated atoll in the Marshall Islands. Enewetak was the site of 43 nuclear explosions including Mike, the first H-bomb (which erased one of the islands in the chain.)

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Two wheeled robocars and the Twill

I have mostly written about 3 and 4 wheeled Robocars, even when the vehicles are narrow and light. Having 3 or 4 wheels of course means stability when stopped or slow, but I have also been concerned that even riding a 2 wheeled vehicle like a motorcycle requires a lot of rider participation. It is necessary to lean into turns. It's disconcerting being the stoker on a tandem bicycle or the passenger on a motorcycle, compared to being a car passenger. You certainly don't imagine yourself reading a book in such situations.

On the other hand 3/4 wheeled vehicles have their disadvantages. They must have a wide enough wheelbase to be stable because they can't easiliy lean. In addition, for full stability you want to keep their center of gravity as low as you can. The extra width means a lot more drag, unless you have a design like the Aptera Motors entrant in the Progressive 100mpg X-prize, which puts the wheels out to the sides.

I recently met Chris Tacklind, who has a design-stage startup called Twill Tech. They have not produced a vehicle yet, but their concepts are quite interesting. Their planned vehicle, the Twill, has two wheels but uses computer control to allow it to stay stable when stopped. It does this by slight motions of the wheels, the same way that pro cyclists will do a track stand. They believe they can make a 2 wheeled electric motorcycle that can use this technique to stay stable when stopped, though it would need to extend extra legs when parked.

This is intended to be an enclosed vehicle, both for rider comfort and lower drag. The seat is very different from a motorcycle seat, in that you do not sit astride the vehicle, but in a chair similar to a spacecraft's zero-G chair.

In addition, the vehicle is designed to have the rear wheel on a lever arm so that it can stand almost upright when stopped and then slope down low, with the rider reclined, at higher speeds. The reclined position is necessary for decent drag numbers at speed -- the upright human creates a lot of the drag in a bicycle or motorcycle. However, the upright position when slow or stopped allows for much easier entry and exit of the vehicle. As everybody knows, really low cars are harder to get in and out of. Twill is not the first company to propose a vehicle which rises and lowers. For example the MIT CityCar plan proposes this so the vehicles can stack for parking. Even without stacking, such designs can park in a much smaller space.

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Tales of the Michael Jackson lottery, eBay and security

I've been fascinated of late with the issue of eBay auctions of hot-hot items, like the playstation 3 and others. The story of the Michael Jackson memorial tickets is an interesting one.

17,000 tickets were given out as 8,500 pairs to winners chosen from 1.6 million online applications. Applicants had to give their name and address, and if they won, they further had to use or create a ticketmaster account to get their voucher. They then had to take the voucher to Dodger stadium in L.A. on Monday. (This was a dealbreaker even for honest winners from too far outside L.A. such as a Montreal flight attendant.) At the stadium, they had to present ID to show they were the winner, whereupon they were given 2 tickets (with random seat assignment) and two standard club security wristbands, one of which was affixed to their arm. They were told if the one on the arm was damaged in any way, they would not get into the memorial. The terms indicated the tickets were non-transferable.

Immediately a lot of people, especially those not from California who won, tried to sell tickets on eBay and Craigslist. In fact, even before the lottery results, people were listing something more speculative, "If I win the lottery, you pay me and you'll get my tickets." (One could enter the lottery directly of course, but this would increase your chances as only one entry was allowed, in theory, per person.)

Both eBay and Craigslist had very strong policies against listing these tickets, and apparently had staff and software working regularly to remove listings. Listings on eBay were mostly disappearing quickly, though some persisted for unknown reasons. Craiglist listings also vanished quickly, though some sellers were clever enough to put their phone numbers in their listing titles. On Craigslist a deleted ad still shows up in the search summary for some time after the posting itself is gone.

There was a strong backlash by fans against the sellers. On both sites, ordinary users were regularly hitting the links to report inappropriate postings. In addition, a brand new phenomenon emerged on eBay -- some users were deliberately placing 99 million dollar bids on any auction they found for tickets, eliminating any chance of further bidding. (See note) In that past that could earn you negative reputation, but eBay has removed negative reputation for buyers. In addition, it could earn you a mark as a non-paying buyer, but in this case, the seller is unable to file such a complaint because their auction of the non-tranferable ticket itself violates eBay's terms.

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A standard OS mini-daemon, saving power and memory

On every system we use today (except the iPhone) a lot of programs want to be daemons -- background tasks that sit around to wait for events or perform certain regular operations. On Windows it seems things are the worst, which is why I wrote before about how Windows needs a master daemon. A master daemon is a single background process that uses a scripting language to perform most of the daemon functions that other programs are asking for. A master daemon will wait for events and fire off more full-fledged processes when they happen.

Review of Downfall / Der Untergang

Last month I released a parody video for the film "Downfall" (known as Der Untergang in German.) Having purchased the movie, I also watched it of course, and here is my review. At least in my case, the existence of the parody brought some new sales for the film. There are "spoilers" of a sort in this review, but of course you already know how it ends, indeed as history you may know almost everything that happens in it, though unless you are a detailed student of these events you won't know all of it.

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Design for a universal plug

I've written before about both the desire for universal dc power and more simply universal laptop power at meeting room desks. This week saw the announcement that all the companies selling cell phones in Europe will standardize on a single charging connector, based on micro-USB. (A large number of devices today use the now deprecated Mini-USB plug, and it was close to becoming a standard by default.) As most devices are including a USB plug for data, this is not a big leap, though it turned out a number of devices would not charge from other people's chargers, either from stupidity or malice. (My Motorola RAZR will not charge from a generic USB charger or even an ordinary PC. It needs a special charger with the data pins shorted, or if it plugs into a PC, it insists on a dialog with the Motorola phone tools driver before it will accept a charge. Many suspect this was to just sell chargers and the software.) The new agreement is essentially just a vow to make sure everybody's chargers work with everybody's devices. It's actually a win for the vendors who can now not bother to ship a charger with the phone, presuming you have one or will buy one. It is not required they have the plug -- supplying an adapter is sufficient, as Apple is likely to do. Mp3 player vendors have not yet signed on.

USB isn't a great choice since it only delivers 500ma at 5 volts officially, though many devices are putting 1 amp through it. That's not enough to quickly charge or even power some devices. USB 3.0 officially raised the limit to 900ma, or 4.5 watts.

USB is a data connector with some power provided which has been suborned for charging and power. What about a design for a universal plug aimed at doing power, with data being the secondary goal? Not that it would suck at data, since it's now pretty easy to feed a gigabit over 2 twisted pairs with cheap circuits. Let's look at the constraints

Smart Power

The world's new power connector should be smart. It should offer 5 volts at low current to start, to power the electronics that will negotiate how much voltage and current will actually go through the connector. It should also support dumb plugs, which offer only a resistance value on the data pins, with each resistance value specifying a commonly used voltage and current level.

Real current would never flow until connection (and ground if needed) has been assured. As such, there is minimal risk of arcing or electric shock through the plug. The source can offer the sorts of power it can deliver (AC, DC, what voltages, what currents) and the sink (power using device) can pick what it wants from that menu. Sinks should be liberal in what they take though (as they all have become of late) so they can be plugged into existing dumb outlets through simple adapters.

Style of pins

We want low current plugs to be small, and heavy current plugs to be big. I suggest a triangular pin shape, something like what is shown here. In this design, two main pins can only go in one way. The lower triangle is an optional ground -- but see notes on grounding below.

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Panoramas of Israel

Back in March, I took my first trip to the middle east, to attend Yossi Vardi's "Kinnernet" unconference on the shores of lake Kinneret, also known as the Sea of Galilee. This is an invite-only conference and a great time, but being only 2 days long, it's hard to justify 2 days of flying just to go to it. So I also conducted a tour of sites in Israel and a bit of Jordan.

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The overengineering and non-deployment of SSL/TLS

I have written before about how overzealous design of cryptographic protocols often results in their non-use. Protocol engineers are trained to be thorough and complete. They rankle at leaving in vulnerabilities, even against the most extreme threats. But the perfect is often the enemy of the good. None of the various protocols to encrypt E-mail have ever reached even a modicum of success in the public space. It's a very rare VoIP call (other than Skype) that is encrypted.

The two most successful encryption protocols in the public space are SSL/TLS (which provide the HTTPS system among other things) and Skype. At a level below that are some of the VPN applications and SSH.

TLS (the successor to SSL) is very widely deployed but still very rarely used. Only the most tiny fraction of web sessions are encrypted. Many sites don't support it at all. Some will accept HTTPS but immediately push you back to HTTP. In most cases, sites will have you log in via HTTPS so your password is secure, and then send you back to unencrypted HTTP, where anybody on the wireless network can watch all your traffic. It's a rare site that lets you conduct your entire series of web interactions entirely encrypted. This site fails in that regard. More common is the use of TLS for POP3 and IMAP sessions, both because it's easy, there is only one TCP session, and the set of users who access the server is a small and controlled set. The same is true with VPNs -- one session, and typically the users are all required by their employer to use the VPN, so it gets deployed. IPSec code exists in many systems, but is rarely used in stranger-to-stranger communications (or even friend-to-friend) due to the nightmares of key management.

TLS's complexity makes sense for "sessions" but has problems when you use it for transactions, such as web hits. Transactions want to be short. They consist of a request, and a response, and perhaps an ACK. Adding extra back and forths to negotiate encryption can double or triple the network cost of the transactions.

Skype became a huge success at encrypting because it is done with ZUI -- the user is not even aware of the crypto. It just happens. SSH takes an approach that is deliberately vulnerable to man-in-the-middle attacks on the first session in order to reduce the UI, and it has almost completely replaced unencrypted telnet among the command line crowd.

I write about this because now Google is finally doing an experiment to let people have their whole gmail session be encrypted with HTTPS. This is great news. But hidden in the great news is the fact that Google is evaluating the "cost" of doing this. There also may be some backlash if Google does this on web search, as it means that ordinary sites will stop getting to see the search query in the "Referer" field until they too switch to HTTPS and Google sends traffic to them over HTTPS. (That's because, for security reasons, the HTTPS design says that if I made a query encrypted, I don't want that query to be repeated in the clear when I follow a link to a non-encrypted site.) Many sites do a lot of log analysis to see what search terms are bringing in traffic, and may object when that goes away.

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Secrets of the "Clear" airport security line

Yesterday it was announced that "Clear" (Verified ID Pass) the special "bypass the line at security" card company, has shut its doors and its lines. They ran out of money and could not pay their debts. No surprise there, they were paying $300K/year rent for their space at SJC and only 11,000 members used that line.

As I explained earlier, something was fishy about the program. It required a detailed background check, with fingerprint and iris scan, but all it did was jump you to the front of the line -- which you get for flying in first class at many airports without any background check. Their plan, as I outline below, was to also let you use a fancy shoe and coat scanning machine from GE, so you would not have to take them off. However, the TSA was only going to allow those machines once it was verified they were just as secure as existing methods -- so again no need for the background check.

To learn more about the company, I attended a briefing they held a year ago for a contest they were holding: $500,000 to anybody who could come up with a system that sped up their lines at a low enough cost. I did have a system, but also wanted to learn more about how it all worked. I feel sorry for those who worked hard on the contest who presumably will not be paid.

The background check

Use the battery to power AC startup surge in an RV

Many RVs come with generators, and the air conditioner is the item that demands it be a high power generator. The Generator needs to be big enough to run the AC, and in theory let you do other things like microwave when you run it. It also has to be big enough to handle the surge that the AC motor takes when the AC starts up.

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Anti-atrocity system with airdropped video cameras

Our world has not rid itself of atrocity and genocide. What can modern high-tech do to help? In Bosnia, we used bombs. In Rwanda, we did next to nothing. In Darfur, very little. Here's a proposal that seems expensive at first, but is in fact vastly cheaper than the military solutions people have either tried or been afraid to try. It's the sunlight principle.

First, we would mass-produce a special video recording "phone" using the standard parts and tools of the cell phone industry. It would be small, light, and rechargeable from a car lighter plug, or possibly more slowly through a small solar cell on the back. It would cost a few hundred dollars to make, so that relief forces could airdrop tens or even hundreds of thousands of them over an area where atrocity is taking place. (If they are $400/pop, even 100,000 of them is 40 million dollars, a drop in the bucket compared to the cost of military operations.) They could also be smuggled in by relief workers on a smaller scale, or launched over borders in a pinch. Enough of them so that there are so many that anybody performing an atrocity will have to worry that there is a good chance that somebody hiding in bushes or in a house is recording it, and recording their face. This fear alone would reduce what took place.

Once the devices had recorded a video, they would need to upload it. It seems likely that in these situations the domestic cell system would not be available, or would be shut down to stop video uploads. However, that might not be true, and a version that uses existing cell systems might make sense, and be cheaper because the hardware is off the shelf. It is more likely that some other independent system would be used, based on the same technology but with slightly different protocols.

The anti-atrocity team would send aircraft over the area. These might be manned aircraft (presuming air superiority) or they might be very light, autonomous UAVs of the sort that already are getting cheap in price. These UAVs can be small, and not that high-powered, because they don't need to do that much transmitting -- just a beacon and a few commands and ACKs. The cameras on the ground will do the transmitting. In fact, the UAVs could quite possibly be balloons, again within the budget of aid organizations, not just nations.

Authenticated actions as an alternative to login

The usual approach to authentication online is the "login" approach -- you enter userid and password, and for some "session" your actions are authenticated. (Sometimes special actions require re-authentication, which is something my bank does on things like cash transfers.) This is so widespread that all browsers will now remember all your passwords for you, and systems like OpenID have arise to provide "universal sign on," though to only modest acceptance.

Another approach which security people have been trying to push for some time is authentication via digital signature and certificate. Your browser is able, at any time, to prove who you are, either for special events (including logins) or all the time. In theory these tools are present in browsers but they are barely used. Login has been popular because it always works, even if it has a lot of problems with how it's been implemented. In addition, for privacy reasons, it is important your browser not identify you all the time by default. You must decide you want to be identified to any given web site.

I wrote earlier about the desire for more casual athentication for things like casual comments on message boards, where creating an account is a burden and even use of a universal login can be a burden.

I believe an answer to some of the problems can come from developing a system of authenticated actions rather than always authenticating sessions. Creating a session (ie. login) can be just one of a range of authenticated actions, or AuthAct.

To do this, we would adapt HTML actions (such as submit buttons on forms) so that they could say, "This action requires the following authentication." This would tell the browser that if the user is going to click on the button, their action will be authenticated and probably provide some identity information. In turn, the button would be modified by the browser to make it clear that the action is authenticated.

An example might clarify things. Say you have a blog post like this with a comment form. Right now the button below you says "Post Comment." On many pages, you could not post a comment without logging in first, or, as on this site, you may have to fill other fields in to post the comment.

In this system, the web form would indicate that posting a comment is something that requires some level of authentication or identity. This might be an account on the site. It might be an account in a universal account system (like a single sign-on system). It might just be a request for identity.

Your browser would understand that, and change the button to say, "Post Comment (as BradT)." The button would be specially highlighted to show the action will be authenticated. There might be a selection box in the button, so you can pick different actions, such as posting with different identities or different styles of identification. Thus it might offer choices like "as BradT" or "anonymously" or "with pseudonym XXX" where that might be a unique pseudonym for the site in question.

Now you could think of this as meaning "Login as BradT, and then post the comment" but in fact it would be all one action, one press. In this case, if BradT is an account in a universal sign-on system, the site in question may never have seen that identity before, and won't, until you push the submit button. While the site could remember you with a cookie (unless you block that) or based on your IP for the next short while (which you can't block) the reality is there is no need for it to do that. All your actions on the site can be statelessly authenticated, with no change in your actions, but a bit of a change in what is displayed. Your browser could enforce this, by converting all cookies to session cookies if AuthAct is in use.

Note that the first time you use this method on a site, the box would say "Choose identity" and it would be necessary for you to click and get a menu of identities, even if you only have one. This is because a there are always tools that try to fake you out and make you press buttons without you knowing it, by taking control of the mouse or covering the buttons with graphics that skip out of the way -- there are many tricks. The first handover of identity requires explicit action. It is almost as big an event as creating an account, though not quite that significant.

You could also view the action as, "Use the account BradT, creating it if necessary, and under that name post the comment." So a single posting would establish your ID and use it, as though the site doesn't require userids at all.

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ClariNet history and the 20th anniversary of the dot-com

Twenty years ago (Monday) on June 8th, 1989, I did the public launch of ClariNet.com, my electronic newspaper business, which would be delivered using USENET protocols (there was no HTTP yet) over the internet.

ClariNet was the first company created to use the internet as its platform for business, and as such this event has a claim at being the birth of the "dot-com" concept which so affected the world in the two intervening decades. There are other definitions and other contenders which I discuss in the article below.

Apple blocks iPhone App because EFF blog points to my Downfall Parody

Last week, I posted a pointer to my parody of a famous clip from the movie Downfall and I hope you enjoyed it. While the EFF itself didn't make this video, I do chair the foundation and they posted a pointer to it on the "Deep Links" blog. All well and good.

Some time earlier, an iPhone app developer put together an iPhone app which would display the EFF blog feed. This wasn't an EFF effort, but the EFF gave them permission to put the logo in the app.

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