Adi Shamir's cryptographic secret shaing scheme

Maybe some people already know about this, but I thought this article about secret sharing was pretty interesting.

Basically, this is a cryptographic way to give out n keys, and then encrypt something so that you only need t of these to read it. (Where t <= n). The best part is that, Shamir's scheme, having t-1 or fewer keys gives no information about the plaintext.

I haven't heard of many practical applications of this-- despite the fact that it seems useful. The cynic in me says that by the time we finally start figuring out good uses for all this stuff, quantum computers will come on to the scene and overturn the apple cart.


"The Transparent Society"

In The Transparent Society, science fiction author David Brin write about what he sees as the future of privacy.

Brin starts by assuming that technology will destroy the possibility of true privacy in the future. This may seem like an unreasonable assumption to some, but it's actually not that hard to believe. Each generation of surveillance devices gets smaller and cheaper. The technologies that destroy the privacy of everyday people just keep getting better and better.

Image a city with a camera on each and every city street, all recording. This is not science fiction-- this is science fact in cities like London. Even if technological progress stopped tomorrow, we would still have to deal with the realities of life in the digital age. The 20th century has brought us accurate sensors, cheap and efficient wireless data transfer technologies, huge computer power, and vast databases.

Given these facts, Brin argues, we have to decide between two possible futures. In one future, which he labels society A, massive data is collected about citizens-- but it is locked away, far beyond the reach of most average people. Only the powerful, the wealthy, and the well-connected can get access to it. There may be some effort to promote the idea that there isn't any surveillance going on, but surveillance will be more or less continuous, especially in public places.

In another society, which Brin calls society B, people have come to accept the omnipresent data collection tools like cameras and microphones, and the huge databases of personal information that they feed into. But instead of restricting access, the data is open for all to see. This is the "transparent society."

In a nutshell, Brin argues that the Transparent Society, while it regrettably gives up some of our customary ideas about privacy, preserves the essential features of democracy. With freedom of information, he argues, people are free to offer informed criticism about the government and other institutions. And perhaps the people themselves can spot petty crime and flag potentially dangerous situations before they become a problem.

Society A, by contrast, is authoritarian by its very nature, since it vests information (which is power) in the hands of the elite. And no matter how many laws are passed, it seems unlikely that politicians and government agencies will keep their hands off of this data.

Lately, it seems that the US government has dropped even the pretense of respecting the confidentiality of trans-national calls. I guess there is still some issue as to whether this will hold up in the courts. Even if it doesn't, though, does anyone really doubt that the DHS will have the final say on this matter?

I don't really know how I feel about the Transparent Society. At its heart, it seems like a good idea. If our privacy is really an illusion, why not destroy that illusion-- rip it away and reveal the true reality. But people cherish their illusions, especially in politics, and I don't think this idea will gain much ground.


The Other Road Ahead

In The Other Road Ahead, Paul Graham talks about why more and more software in the future may be server-based. He also talks about ViaWeb, the dot-com startup company he co-founded.

I think the name of this essay is a play on "The Road Ahead," a book written by Bill Gates. If so, it's an apt play on words, because if software becomes more server-based, Microsoft could stand to lose out.

Graham writes:
When you own a desktop computer, you end up learning a lot more than you wanted to know about what's happening inside it... Ordinary users shouldn't even know the words "operating system," much less "device driver" or "patch."

There is now another way to deliver software that will save users from becoming system administrators. Web-based applications are programs that run on Web servers and use Web pages as the user interface. For the average user this new kind of software will be easier, cheaper, more mobile, more reliable, and often more powerful than desktop software.

In a future like this, the main use of a desktop computer would be to provide users with web access. All of the hard work would be done on the "server-side" by corporations maintaining dedicated servers.

This vision is attractive. Individuals would no longer have to remember to back up their files-- sysadmins would do it for them, just like in the "old days" of mainframe computing. Collaboration over the network would become easier. Instead of emailing back and forth MS Word documents, you could perhaps compose them jointly in real time. And software piracy would become almost impossible, because customers would never actually have the software on their computers!

I can see some disadvantages, too. When you put your data on a central server, you are trusting the people there not to misuse it. How much trust can we really put in these sysadmins? Also, the computer stops being self-sufficient, and starts becoming more and more dependent on the network. This might not be such a bad thing, all things considered... but it does create another point of failure. Graham responds to this by pointing out that server-side software eliminates a lot of points of failure, too, by centralizing and professionalizing administration tasks. I guess I agree.

Personally, I keep all of my data on my own machine as much as possible, and back that up. Still, the idea of collaborating with people in real-time is interesting.