Adam Lloyd

Scenario

Sun, 25 Oct 2009 05:48:40 -0400

Alice is the wife of jealous Bob. She wants to communicate with her secret lover Carl. She creates two keys, one intended to be kept secret, the other intended to be sacrificed. She passes the secret key (or both) to Carl.
Alice constructs a harmless message M1 about boring math stuff for Carl (intended to be revealed to Bob in case of discovery) and a burning love letter M2 to Carl. She constructs a cipher-text C out of both messages M1, M2 and emails it to Carl.
Carl uses his key to decrypt M2 and possibly M1 (in order to know the fake message, too).
Bob finds out about the email to Carl, becomes suspicious and forces Alice to decrypt the message.
Alice uses the sacrificable key and reveals the message M1 about boring math stuff to Bob. Since Bob does not know the other key, he has to assume that there is no other message M2.

This is a possible scenario for the use of deniable encryption, found on Wikipedia.

I laughed out loud when I read this. I’ll now state the probably obvious fact that examples like this are awesome. They’re awesome for the reader because they’re goofy and therefore engaging, and they’re awesome for the writer because they’re fun to make. (They might not, of course, be so awesome for the characters involved — like Bob.)

What’s more, I posit that this fun-is-good principle can be applied to anything.

Take code, for example: certainly, you can write some off-the-wall program that is completely unintelligible. I think, however, that you can also mix goofiness and good form in such a way that you increase readability.

I try to do this with programming assignments for my classes. I do it partly out of consideration for myself — it makes it more fun — and partly to brighten the day and ease the job of some poor teaching assistant who’s already looked over fifty other versions of the same program.

As another example, I attended a lecture just last week on Turing machines. What made it memorable was that after mentioning some new variation on the standard model, the professor would sometimes pause to point out that “of course, if you have four arms, you’re no less powerful than a person with one — right?”

There’s one problem, unfortunately, and that is that it can be hard to get right. The deniable encryption scenario is effective because it is plausible. I remember some outrageous scenario given by one of my professors* last year. It involved voting machines being connected to a giant panel of lights in some room where people watched the flashes to count the votes coming in, and it would have been a good use for multiplexors or demultiplexors or something — and that’s the point: I remember the scenario quite well, but I have no idea what it was for.

Plausibility, luckily, is a fairly easy test. Metaphor is similar: to be effective, it requires a tight mapping between its world and that of whatever it’s meant to explain. If this isn’t in place, a metaphor could both fail to accomplish its purpose as an effective teaching tool or mnemonic and lead you astray in your understanding, but major inconsistencies in a metaphor are easy to spot.

The code example is a bit harder. Minor flaws in a scenario or metaphor might easily go unnoticed, but bad or ugly code is more obviously bad or ugly. Worse still, you might have the wittiest comments or symbol names imaginable, but they won’t redeem your code if it’s stylistically atrocious. It’s akin to showing up to a party without having showered in a week: you might be the funniest person in the world, but you’ll reek badly enough that no one will want to be around to listen to your jokes**.

Discouraged now that I’ve argued that fun is good and that getting good fun right can be difficult? That’s about the worst thing you can be. I’m not a fan of making grand “anyone can do x” statements, but it’s appropriate here: anyone can get good fun right. I used to be terrible at explaining things to other people. I persisted, though, and I’ve gotten better at making things easy and memorable. The key is not being afraid to get it wrong. Sure, you will get it wrong, but if you’re afraid of that, you won’t be able to get it right.

Have fun with what you do, and do so without fear of doing it wrong. You’ll very quickly find yourself doing your own awesome things.

* This particular professor, however, was awesome, and this one goofy and ineffective example was such a rarity that I feel bad using it as my example of a goofy and ineffective example.

** Fortunately, I’ve noticed a positive correlation between people who shower often and programmers who write good code, so if you’re a programmer who’s not very susceptible to one of these problems I’d expect you to be similarly unaffected by the other.

New monospaced font on CTAN: Inconsolata

Thu, 01 Oct 2009 23:19:27 -0400

New monospaced font on CTAN: Inconsolata:

Since I’m back at college and LaTeX-ing things again, I was very excited to find this.

Inconsolata is easily the most beautiful monospaced font I’ve ever seen, and it might be my favorite font, period. (Coincidentally, I’ve just designed a theme using it.)

Also, hello again. Update: It turns out Tumblr’s done...

Tue, 29 Sep 2009 13:54:00 -0400

Also, hello again.

Update: It turns out Tumblr’s done some cool stuff with its theme system. This uses it. (Ever wanted your blog to have the option to have a smiling header that winks on mouseover? Now it can.)

Were I not vegetarian, I'd be making some clichéd comment about fish.

Fri, 21 Aug 2009 05:07:00 -0400

To be honest, I thought this blog had a much lower signal-to-noise ratio than it actually does. I was pleasantly surprised with I dug back a few pages. (This is not to say that it’s a healthy tomato, just that I’d overestimated the amount of rot you’d have to cut out if you wanted to use it in a good salad.)

On a larger scale, however, it itself is noise. At times, I make valid points (I hope), but they are insignificant points ineloquently made. I believe that—right now—there is always some way I could be better using my time than posting here. It has failed in its original purpose (of refreshing my wilting writing skills) by deteriorating into a collection of short-form silliness and long, rambling rants. Even calling this “a notebook of sorts” does not justify my using it, as anything that I post here to “note” would be better noted elsewhere (Delicious for links, for example).

I therefore intend to silence myself. I have no doubt that I will be back in some guise at some point with something more important to say and a better idea of how to say it. Until then, I’m not going to waste time not saying important things well.

My microblog(s) will remain alive and will hopefully become more worthwhile than they are now. I would also like to think that there will be increased activity from me on GitHub (or perhaps on BitBucket, since I use Mercurial now). This will probably remain; it would feel dishonest to tear it down and pretend I haven’t been here this whole time.

To the best of my knowledge, no one follows me for Cirqueti news, but you can follow Cirqueti to get that in a more succinct and accurate form; I’m also pretty sure I’ve linked to all of my theme blogs here if you want any developments on those.

(That was the end. I’m not good at finality.)

Retractions, Updates, and Notes

Fri, 21 Aug 2009 04:08:00 -0400

I falsely accused KDE’s Konsole of not responding to C-PgUp. This is ridiculous and not the case. I was using screen at the time, and I hadn’t yet learned about its scrollback buffer.

My embedding things in strange ways is apparently common when I am overtired.

I meant no offense by this. Someone reblogged this to complain about me being rude, and it’s bugged me for some time now. I honestly didn’t mean for it to sound rude at all, and I apologize if it did.

My effort to go paperless where possible has apparently been succeeding. However, I am now using a local installation of MediaWiki for (what I hope will be) an information catch-all. (This is especially good given that I’ve just switched back to Vim.)

Mercurial and I couldn’t stay apart for long. I now use Mercurial exclusively, as its interface agrees with me more than Git’s. I also find Mercurial’s bookmarks to be beautifully simple in comparison to Git’s branches. (I’m still not a fan of patch queues, but that’s mostly because I haven’t had proper occasion to use them.)

Notadouche is no longer dead. Though, to be honest, I have no idea how it’s alive at the moment, and I wouldn’t expect it to last long.

I needed to read something on Facebook. I disabled English (Pirate) and have not gone back.

Switching to madwifi fixed the instability in my Ubuntu machine. Also, madwifi has few issues of its own if you add it (ath_pci) to the proper array (SUSPEND_MODULES, perhaps?) in your ACPI configuration.

That last point is rather irrelevant, since my Ubuntu machine is now a Fedora machine. ~~Also, the ath5k instability seems fixed.~~ (I spoke too soon.)

Deleting my music library has worked out just fine. I am also in the process of converting it (the copy on my external hard drive, that is) from Ogg Vorbis to AAC, as the advantages of not doing so are now purely ideological.

I have not made much progress in learning Japanese, mostly because an ear infection robbed me of my cognitive ability very shortly after I started. This is very definitely a temporary stall, however.

An interesting (indirect) effect of my ear ailment is that I can now probably type better than sudo’s pet ferret. My typing accuracy has increased noticeably. (I do not recommend ear infections as a means of improving your own typing accuracy, however. It likely won’t work.)

ASCIIquarium is apparently KDE-related. It is not shown in xscreensaver-demo. This is a shame, since I’m currently running awesome and use xscreensaver with it.

After I finished complaining, my installation of Fedora went well. The only slight bump afterward was getting reasonable LCD font smoothing working.

Somewhere between “more-or-less functional” and...

Thu, 20 Aug 2009 09:23:07 -0400

Somewhere between “more-or-less functional” and “so far beyond overtired that reality starts twisting to make me super-productive”, there’s this fun stage where I do things like run a nested X session in a nested X session. ‘Twas quite a fun moment when I managed to get my pointer and keyboard captured by both Xephyrs at once.

KDEWM=awesome startx was a failed experiment. (Yes, that is my...

Thu, 20 Aug 2009 05:15:57 -0400

KDEWM=awesome startx was a failed experiment. (Yes, that is my KDE panel in the center of the screen. Yes, clicking it does cause xcompmgr to make my KDE background 20% transparent, allowing my awesome-set background to show through.)

It wasn’t totally my fault: the awesome wiki told me I could do it.

langer: “when you don’t create things, you become defined by your tastes rather than ability. your...

Wed, 19 Aug 2009 17:54:26 -0400

langer:

“when you don’t create things, you become defined by your tastes rather than ability. your tastes only narrow & exclude people. so create.”

—why the lucky stiff, quoted two weeks ago by christmasgorilla.

Today, why vanished from the internet.

I find this quite upsetting, in part because I just started the (Poignant) Guide this morning and have nearly finished the last chapter I downloaded before it went offline.

I certainly hope that the disappearance of his online persona is not indicative of anything awful happening to the corresponding offline character.

Dirty version of my desktop.

Mon, 17 Aug 2009 05:36:47 -0400

Dirty version of my desktop.

Suddenly, I looked at my desktop, and I thought, Wow, I really...

Mon, 17 Aug 2009 05:30:00 -0400

Suddenly, I looked at my desktop, and I thought, Wow, I really like the way that looks.

This is the result of a few tweaks every now and then (the integral of my KDE customizations to date, if you will). I’ve only pictured my night activity here, but I use both my morning (which generally uses a light background) and night (which generally uses a dark background) activities fairly regularly. Although they differed for a while (night had a binary clock under the activity bar, while morning had a fuzzy clock), they now have the same widget layout.

The activity bar has stayed in the top left corner since I first added it. I’ve ditched the extra clock underneath it in favor of a small plasmoid playing out Conway’s Game of Life. (The value of this to me is not to be scoffed at, actually, as it’s a quite useful relaxation and focus aid.) I also replaced the standard digital clock at the right of the panel with a small binary clock. This was initially just done for the novelty, but I’ve found that it prevents time obsession without removing a clock entirely.

Although I’d been using the now-default Air plasma theme for a while, these screenshots show the Glassified theme, which can be found on KDE-Look and downloaded via KDE’s desktop settings utility. To match it, I’ve also switched to one of the provided dark color schemes in KDE. I’ve never been able to stand using a dark color scheme before, but this one remains both attractive and usable in Qt (with the Oxygen style, at least).

The wallpaper is pat1926’s Moraine Lake.

Edit: I should also add that, somewhat to my dismay, the cashew has become much smaller in KDE 4.3.

I have my Toshiba laptop set up for my mother. For various...

Sun, 16 Aug 2009 13:46:00 -0400

I have my Toshiba laptop set up for my mother. For various reasons (including F-Spot’s acting like it spends way too much time at bars), I think she’d be better off using KDE. For various other reasons, I thought I would be better off installing Fedora than turning the existing Ubuntu install into Kubuntu. Unfortunately, Fedora, as contained on the KDE live CD, seems determined to change my mind.

My /home partition, which has been formatted quite happily as ReiserFS for several years now (through, I might add, several previous Fedora installs), shows up in the installer as having no type. This isn’t much of an issue, since I can just clear out /home after installation and edit the fstab to suit my needs; however, I think it’s rather ridiculous to pretend that ReiserFS doesn’t exist. As far as I can remember, it was always necessary to pass an option to the installer on boot in order to create ReiserFS partitions. The reason, I believe, was that the filesystem doesn’t support the file attributes needed for SELinux. As Fedora enables SELinux by default, this makes some sense. Refusing to acknowledge existing ReiserFS filesystems, though, seems overkill (and annoying). (Coincidentally, the NTFS “Toshiba Volume” that exists on the hard drive has its type correctly noted.)

That said, it probably wouldn’t be a bad idea to convert that partition to ext4.

Speaking of ext4, I didn’t realize that there were recent distros that couldn’t boot from it. After all, Ubuntu’s been doing it since at least April, and I generally regard Fedora as the more up-to-date distro. (It was, after all, the distro to pioneer the breaking of many a system with PulseAudio.) Unfortunately, though it was happy to offer ext4 as the default filesystem type choice, the Fedora installer refuses to create a partition layout that has the OS booting from an ext4 partition.

Fine, I thought, a bit disgruntled, I’ll just make it ext3, then. Well, no. The installer spits out something about the / filesystem not matching the live image. “It must be formatted as ext4.”

Presumably, creating a separate ext3 /boot partition is a solution to the “ext4 and not ext4” paradox. This will be the first time I have ever made a separate partition for /boot. It will also be the first time I have been in any way forced into a partition setup by a distro’s installer.

(Update: It seems this is what they want you to do, since the installer changes the type to ext3 as soon as you type “/boot” as the mount point.)

I don’t know whose doing this is—whether it came...

Sun, 16 Aug 2009 06:29:07 -0400

I don’t know whose doing this is—whether it came with KDE or xscreensaver, though I doubt it’s the latter because I’ve never seen this before and don’t recall updating that recently—but I just discovered a screensaver called “Asciiquarium.”

If this isn’t one of the best things ever, I don’t know what is.

WTF indeed.

Sat, 15 Aug 2009 00:09:17 -0400

WTF indeed.

"I saw `cout’ being shifted “Hello world” times to the left and stopped right..."

Fri, 14 Aug 2009 19:19:35 -0400

“I saw `cout’ being shifted “Hello world” times to the left and stopped right there.”

- Steve Gonedes [Spotted in a signature on python-announce]

“This system uses 5 1/4...

Thu, 13 Aug 2009 16:31:00 -0400

“This system uses 5 1/4 inch…diskettes.”

Pictured is one such relic, eclipsing half of my ThinkPad’s keyboard and laid out next to a six-inch ruler to verify that it is, indeed, five and a quarter inches to a side. Presumably, this mini floppy disk (and yes, it actually is floppy) would not work in Mr. Smith’s Heathkit H89, since it is marked “double density.”

I’m not really sure why I have it, and I can only guess as to whether it actually contains “read+solve math problems”; the only hardware I had that was capable of using it became dysfunctional and was discarded way back when my age would have fit in two or three bits.

It’s interesting to think that I’m one of the probably very few people in my generation to have used these. (It’s a shame, too—some of the best games came on 5 1/4 inch floppies.)

"Dear Sirs: I have just purchased a Heathkit H89 computer system and would like to order two boxes..."

Thu, 13 Aug 2009 16:02:00 -0400

“

Dear Sirs:

I have just purchased a Heathkit H89 computer system and would like to order two boxes of diskettes for it. This system uses 5 1/4 inch, hard-sectored, ten-sector, single-sided, single-density diskettes.

Enclosed is my check for $45.00. Please rush this order, as I can not use my system before they arrive.

Sincerely,

Mr. Smith

”

- GNU Typist: typing drill and history lesson, all in one.

The kittens got baths.

Wed, 29 Jul 2009 15:08:00 -0400

The kittens got baths.

"My pet ferret can type better than you!"

Sun, 26 Jul 2009 17:59:21 -0400

“My pet ferret can type better than you!”

- sudo, after I mistyped my password.

Compute for Good/Compute for Social Change

Fri, 24 Jul 2009 13:46:38 -0400

Compute for Good/Compute for Social Change:

How can computing help make the world a better place? Why is providing connectivity important? How best to do so? How can computers help a nation heal? Can we avoid wars and track diseases in time to avoid epidemics? We explore problems faced by developing countries and underserved populations from a computer science perspective.

A course from Georgia Tech. Awesome!

PyKanjiCard

Thu, 16 Jul 2009 09:38:42 -0400

PyKanjiCard:

PyKanjiCard is a flash card program to aid learning Japanese written words, in hiragana, katakana and kanji. You can select words composed only by characters you already know. It is written in Python, using PyGTK.