With so very many computers in the world, they cannot all be connected directly. Instead, messages between computers are routed around the globe by glorious web of intermediary computers, all working in tandem to get billions of information packets to their intended destinations. If it helps, you can imagine the whole network as an electronic version of UPS.

The beauty of this system is that it is decentralized, efficient, and robust. Lots of computers are all working together to send lots of information, and there is no single point of failure. A concern, however, is privacy. When your computer sends a message, the random assortment of computers that help deliver your message all have a chance to take a peek. If you are merely visiting this website, eavesdropping is hardly a concern. The content of this site is public, so there’s no problem with some nosey computer reading the sites content en route. Sometimes, however, your computer needs to send private information over the internet.

What if you send google your gmail your password? Or log in to your employer’s computer system? Or give amazon your credit card number? In all cases, the message you’re computer is sending needs to be kept secret. What’s needed is a way to put the message in some kind of “locked box”, and that’s where cryptography comes in. When private information is sent, the computers involved can encode their messages using some slightly fancy mathematics. When done properly, only those two computers will be able to decode each others messages (i.e. open each others’ boxes). The intermediate computers routing their messages will no longer be able to read their content.

Lots of folks write software that sends information over the internet, but most of these people are not about to learn how to write cryptographic protocols for securely sending messages in mathematically sealed boxes. Fortunately for everyone, there are standard tools available. One of them, called OpenSSL, implements a secure message transmission protocol called SSL.

Your computer uses SSL every time you visit a web address that begins with “https:” (instead of the standard “http”). When you see the “s”, it means that the messages your computer is sending and receiving are secure (i.e. inside a locked box). If you tell google your gmail password, and your computer is following the SSL protocol properly, your password will be safe from snoopers. Almost all software that sends private information over the internet relies on SSL. This (at least!) brings me to the point of this post.

Last week, the folks who maintain Debian, a popular version of Linux, announced that they had mistakenly altered OpenSSL. As a result, for several years, programs running on a computer using Debian Linux (or a related distribution), and relying on SSL, were critically flawed. Such programs were all sending their secure messages (as well as possibly generating user passwords) using a very small number of random numerical keys. As a result, the encrypted information could be decrypted (i.e. unlocked) by testing all possible keys. In other words, it’s as if OpenSSL, running on Debian Linux, was choosing all of its passwords from a very small dictionary.

Now most people use Windows or Mac OS X at home and at work, but many websites (and other internet services) run on computers using Linux, since it’s free and open source. When your computer sends secure information over the internet, however, you not only rely on your computer’s ability to use SSL correctly, but also on the computer you are communicating with. This computer is very likely to be running Linux, and though only certain versions of Linux were affected, this recently discovery speaks to a very serious problem. This recent (and massive) security flaw was introduced when some poorly informed developer (lots more info here, also here) modified a grand total of two (2) lines of codes. (and if you’re curious how this poor schlub got his position in the first place, here’s your answer)

If you care to read this discussion thread (which is quite technical), you’ll discover that the lines in question were causing a software debugging tool called Valgrind to report errors. The errors were due to OpenSSL telling Linux to read information from a random location in memory. Valgrind was reporting this as a mistake, since normally when a program accesses a random locations in memory, it is a mistake. In this case, however, the random information was being used to generate a random key to securely encrypt information. When the developers told Linux to ignore the two lines of code, they prevented OpenSSL from properly generating random keys. As a result, internet-related programs running on Debian Linux were all encrypting messages using a very small number of keys, which in turn made the encrypted data very easy to unlock (provided the eavesdropper was aware of this shortcoming).

In the world of computers, finding a security flaw is not uncommon, and I wouldn’t normally spend time writing such a long post about such a technical subject. My concern, however, is that this security flaw has not gotten any attention outside of the world of nerdy websites. It seems to me, however, that a computer security flaw of this magnitude (and of course the potential for even larger flaws) is a public policy issue.

A typical security flaw allows an intruder to gain access to a single computer, or perhaps a computer network, but this flaw does all that and more. With so many computers affected for such a long period of time, you have a real potential for economic disruption (dare I say, even a cyberattack).

Furthermore data encrypted by faulty versions of OpenSSL remains vulnerable even now that the flaw has been discovered (and hopefully on most computers, and faulty passwords, fixed). If someone were monitoring and recording encrypted internet communication (I imagine China does this), they could retroactively use information about the OpenSSL flaw to decrypt all sorts of recorded data. Not only would private information be revealed, but compromised passwords would make additional computer systems vulnerable. Incidentally, there are methods for ensuring that encoded information cannot be discovered retroactively, but these methods are not necessarily used by OpenSSL.

So far I’ve found the Macbook Air to be quite lovely. I’ll admit, it’s not the thriftiest purchase I’ve ever made, but it does fit my lifestyle very well. Before last week, I had a 12″ Powerbook that I carried everywhere. The Air fits beautifully in the same bag and is definitely more pleasant to carry. Its screen is also a huge improvement. It’s much brighter and sharper, and I like the extra width as well.

Before I bought this computer, I read a lot of comment threads filled with a bunch of people whining about its supposed shortcomings. So far these complaints have not bothered me one bit.

The DVD drive on my 12″ Powerbook had been broken for years, so I certainly don’t miss having one in my new machine. Also, in my three years owning the Powerbook, I almost never plugged in anything besides an external monitor, an ipod, and a digital camera, so having one USB port is fine by me. Finally, I’ve never carried around a spare laptop battery, so its hardly a sacrifice not to be able to do so now.

One final note: This Ars Technica review reported a very poor experience with the Macbook Air’s battery, but this does not match my own experience. I agree that getting a full five hours of battery life is unlikely, but 4+ is definitely possible depending on what your running (PowerPoint appears to be a bit of a hog). I’ll also note that the first day I got this computer it was running fairly hot and the battery was depleting rapidly. When I opened up Activity Monitor, I noticed that Dashboard had froze up and was using 99% of my CPU. Restarting fixed the problem.

Footage from IBM’s booth at the 1964 worlds fair fills in some of the details (skip to 2:30 if you like) :

As a graduate student in computer science, and general railroad enthusiast, I found their explanation to be dead on. It may not make much sense, but it uses the word “reality” several times, and it’s presented by a guy wearing a tux, so that’s a plus. Regardless, I’m pretty psyched to live in that tundra village.

Today’s technology takes about 10,000 square nanometers to store a bit of data on a chip (a nanometer is 1 billionth of a meter). We can currently build computer chips using wires that are about 70 nanometers wide, but newer nanoscale technology may allow for wires only 5 to 10 nanometers wide. Similarly, it may be able to store a bit of data using less than 100 square nanometers. This would allow us to store terabytes of data on those nifty little usb drives we all have.

Sometimes when a new nanoscale data storage technology is demonstrated, the folks involved (or their company/university) decide to hype it up and put out a press release. With luck, this results in an actual article being written, which in turn results in a post on Engadget or Slashdot or something. When this happens, both the article and the post tend to contain an optimistic claim about when the described may come to market.

Since this is one of the few areas in which I have actual credentials, I’m usually tempted to leave a slightly technical comment pointing out the difficulties that still lie ahead. Since I have this blog, a big ol’ post seemed more appropriate (and hopefully more reusable).

The storage technology demonstrated by Professor Kozicki sounds promising, but this is far from the first time nanoscale storage has been demonstrated (for example, there’s this, or this, or this). When you hear about this type of thing, it’s important to remember that there’s more to building a memory than simply having a medium for storing data. You need a way to control that medium.

Typically when researchers demonstrated a new type of nanoscale storage, they place their device between two electrodes, then use the electrodes to read and write information (this generally involves applying various voltages across the device). Even though the electrodes are small (about 100 nanometers wide), but they are still quite large compared to the device itself.

Even if the device works perfectly, you cannot make a nanoscale memory by simply placing billions of devices between billions of non-nanoscale electrodes. If you do this, it will still take about 10,000 square nanometers to store each bit. For much denser storage, additional nanoscale technology is required.

One promising approach being pursued is to create a grid of nanoscale wires, then position storage devices between each pair of perpendicular wires. As luck would have it, grids of tightly packed nanowires have been produced, and even used to store data. Unfortunately, no one has yet demonstrated a way of efficiently controlling the individual nanowires that make up the grid. Until we have a way to control tightly packed nanowires, we cannot take advantage of nanoscale storage devices.

For the record, I am optimistic that a fully functional nanoscale memory will be produced before 2010, but I think it is very unlikely that any such device will come to market before then.

The great thing about making slides online is that there’s not need to transfer them from one computer to the next (transferring slides sucks, since on Macs and PCs they may look different). Plus if you collaborate on a presentation (as I often do) everyone can edit the slides online. In fact, you can even gchat while both looking at the slides. Also google office provides automatic back up and version history.

The key drawback of using google presentations though is that the app pretty much blows. It’s just nowhere near Powerpoint. For one, it doesn’t automatically resize text, the one things that makes using Powerpoint super fast. It’s true that Apple’s Keynote doesn’t do this either, but the google program doesn’t even let draw lines and boxes or edit themes. This is particularly frustrating since I was able to import existing slides that contained objects I couldn’t edit or create from scratch. I was also surprised I couldn’t embed content using google video (or google images). Putting video in Powerpoint is risky, so this seemed like a potential major selling point. There was also no way to select multiple objects.

Anyway, here’s my sample presentation. You need a google account to view it, and also it doesn’t show up correctly in Safari. Hopefully this app will get a lot better real soon.

Well you probably also want a photo editor. Good thing Adobe just previewed their new online app Photoshop Express. I doubt it comes anywhere close to doing everything Photoshop does, but it’s a start. If you’re looking to edit videos online, Adobe can help with that too.

I’m not really sure about the state of online file storage. As more and more mainstream apps appear online, however, it’d be nice to have a central place to store and organize your online documents. At that point you’d really start to feel like you had your own computer online. If I weren’t busy getting a PhD I’d totally get on this.

I’m probably not going to get a Zonbu, particularly because I don’t want to pay a monthly fee to use a computer (after all, I already pay a monthly fee to host this website). Also it restricts what software you can install (like the iPhone). Still, I’m excited that the Zonbu is out there, because it points to an obvious change in personal computing. In the next five years almost everything most computer do is going to be done over the internet.

Storing your files on the internet is much better than storing them on your home machine. Your home computer will break one day, I promise. If amazon.com is storing your files, they will be fine. When you go buy a new computer, you’ll need a bunch of programs. If those programs are web-based (think google docs & spreadsheets) you won’t need to install them. Also they’ll probably be free, never crash your computer, and you’ll never need to upgrade them (google can add features and fix bugs without you doing a thing)

And the benefits of internet-based computing don’t stop there! If you want to share your files, or collaborate with someone on a document, you can just tell the service storing your files to provide your collaborator access. When your on someone else’s computer, you’ll be able to access your files. Using a free public computer will be as good as using your own.

Where I work you can log on to any computer in the building, and it behaves just like the one at your desk. Your personal settings and files all appear, and everything you do gets automatically backed up. This is exactly what computers like Zonbu allow for, only on a world-wide scale. It’s also just one of the many reasons why fast reliable broadband needs to be more than a luxury in the US.