AKMA’s Random Thoughts

Algorithm rather than algorhythm?

"biometrics" rather than "bioinformatics?"

Well, it gets even more difficult if you think about the likelihood that you probably can't answer some questions the same way 10 years after you setup your DigID as when you first set it up. For example, if I had setup a DigID when I graduated High School, I might have been tempted to include the names of the group I hung out with. Ten years after that I probably would have forgotten half the names, and now at 25 years on I can only remember one or two. What do you do when you can no longer prove you are who you were?

Frank, quite right, don’t know where that came from.

Bioinformatics is a real discipline. It is defined as "the use of computational techniques
to extract meaning from biological data." I have a friend who studies this very topic. Different from biometrics, of course.

But my actual comment is this: Ewan may have missed the point of "what I know" verification. Unlike password, or "concealed knowledge" verification, "what I know" verification depends on shared knowledge, ideally something shared between the verifier and the target only.

For example, AKMA would have no way of knowing who I hung out with in High School. But, without prearrangement, we might be able to settle on the answer to the question, "Where did we eat lunch together on Saturday of the DGI?" Maybe he won't remember, but if he does, it's information that is fairly secure between he and I. The more intimate (sensitive) the information likely to be exchanged, the more likely that a non-pre-negotiated but highly secure verification could be made. If I were to pass some information from me to someone claiming to be my wife, for example, I would have a wealth of possible secure challenges, which are nigh impossible to guess or hack. (Did I eat icecream for desert yesterday?)

The critique that this depends on a prior relationship falls on the fact that any "password" system also requires that we have met before, if only to exchange the password. The only setup I can think of that doesn't are PGP Keys, which use a trust based system. Either way, the verification process depends on shared knowledge rather than concealed knowledge. And I like that much better.

Somehow this reminds me of the time a friend of mine called up in a strange mood and demanded to know "How do I know this is really you" (remember, my friend had called ME) and finally "What's the password?" My answer was "That's easy-- you and I don't HAVE a secret password" which satisfied him completely. It was true, and even in his irrational state he recognized the statement and its tone as being precisely what I would say if I were, in fact, myself.

If we'd _had_ a password, someone could have stolen it or guessed it. But the authentic and spontaneous response is much harder to counterfeit. That's what I think.

--Laura (really; back from Mississippi and glad to have web access again)

That gives us a pretty good starting point to understand a lot more about variables, and that's what we'll be examining next lesson. Those new variable types I promised last lesson will finally make an appearance, and we'll examine a few concepts that we'll use to organize our data into more meaningful structures, a sort of precursor to the objects that Cocoa works with. And we'll delve a little bit more into the fun things we can do by looking at those ever-present bits in a few new ways.

This back and forth is an important concept to understand in C programming, especially on the Mac's RISC architecture. Almost every variable you work with can be represented in 32 bits of memory: thirty-two 1s and 0s define the data that a simple variable can hold. There are exceptions, like on the new 64-bit G5s and in the 128-bit world of AltiVec

The rest of our conversion follows a similar vein. Instead of going through line by line, let's just compare end results: when the transition is complete, the code that used to read:

The rest of our conversion follows a similar vein. Instead of going through line by line, let's just compare end results: when the transition is complete, the code that used to read:

Being able to understand that basic idea opens up a vast amount of power that can be used and abused, and we're going to look at a few of the better ways to deal with it in this article.

Note the new asterisks whenever we reference favoriteNumber, except for that new line right before the return.