Mickey on Emacs 24.4

As he has for the past several releases, Mickey over at Mastering Emacs has perused the NEWS file for the upcoming Emacs 24.4 and produced an informative post on what’s new. There are a couple of good reasons to read his post. The first is obvious: curiosity as to what’s coming. The average Emacs Knight is going to be excited at the prospect of a new release and will want to know what’s in it.

The second reason is advance planning. Most of us have large and complex Emacs initialization systems and each new release can break it in various ways. For example, Emacs 24.4 has removed or renamed several functions that your init.el or associated files might use. Similarly, some commands have had their functionality changed in subtle ways that may interact with your custom Elisp. Finally, new capabilities have been added that may negate the need for some of your custom code.

You can always discover this stuff by reading the NEWS file when you install the new Emacs but I like having advance notice of what I should be looking for. Even if you don’t agree, you know you’re curious so go on over to Mastering Emacs and read Mickey’s post.

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Progress on the Discrete Logarithm Problem

A team of French mathematicians and computer scientists have developed a new algorithm that makes substantial progress on certain types of discrete logarithms. The general discrete log problem is given a and b from a finite field find n also from the finite field such that a = bn. It turns out that this problem has about the same difficulty as factoring and, in fact, the two problems are related.

The discrete logarithm problem is important because its difficulty is what makes the Diffie-Hellman key exchange protocol and elliptic curve cryptography secure. Additionally, progress with the discrete logarithm problem can often be carried over to the factorization problem.

The French team’s algorithm works only for low characteristic finite fields, which means it does not affect Diffie-Hellman or elliptic curve cryptography but does effect certain other less-used cryptosystems. The bottom line is that there’s no reason for panic: all our important asymmetric cryptosystems are still secure. Still, as Bruce Schneier says, attacks only get better.

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No

Why not?

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LispStick!

If you’re a Windows user and want to try Lisp, getting started can be a bit of a hassle. Now Patrick Krusenotto has come to the rescue with LispStick!, a Zip file that has everything you need to get started. Included in the package are

  • SBCL
  • Emacs
  • SLIME
  • Quicklisp

The software is installed in a single directory so you don’t have files scattered all over you file system. You can even run it from a flash drive if you want to carry your Lisp development environment with you.

If you’ve already had some experience with CL, you’ll know that the four pieces of software in the package are really everything you need. Having the easy-to-use Quicklisp available means that you can easily add libraries as you need them, something that was fussy and difficult before Quicklisp. Very nice.

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Data Loss and Reproducible Research

As long-time readers know, I’m a big fan of reproducible research (1, 2, 3, 4, 5, 6, 7). The aspect that I’m particularly interested in is keeping the data, software, and other supporting material together with the source for the actual paper. This is especially convenient with the Emacs/Org mode/Babel combination as many of the above posts discuss.

One thing I hadn’t considered is its role in preventing data loss. UPI is reporting that scientific data is disappearing at an alarming rate. Researchers from the University of British Columbia looked at 516 research papers and tried to locate the data underlying the papers. They found that most of the data was available two years after the papers were published but that the availability of the data dropped off by about 17% for each year after the second.

The problem seems rooted in the fact that the data stays with the researchers. Researchers move, retire, or die making it difficult or impossible to get in touch with them. Even when a researcher can be reached, the data may have been lost or trapped on old media that can no longer be read. Reproducible research by itself doesn’t help with any of those problems, of course, but it can help if the original files are held by the journals that publish the papers. The authors of the University of British Columbia study recommend that journals require authors to upload data to public servers as a condition of publication.

An even better solution is to require that authors generate reproducible research files1 and escrow them with the journal or on public servers set up for that purpose. Keeping digital files readable is a difficult problem—just ask the Library of Congress—but it’s one that’s more suited to professionals than individual researchers, most of whom lack the necessary background and skills.

I’ve long believed that journals should insist that authors submit reproducible research files as part of the publication process. That was to allow other researchers to verify and perhaps extend the original research. As the UPI report makes clear, keeping valuable scientific data from disappearing is an even better reason.

Update dissapearing → disappearing

Footnotes:

1

Ideally, this would be a single file containing the text of the paper, data, calculations, and programs used to manipulate the data. In some cases the data sets or programs may be too large to make that practical but they should all be included in the reproducible research file set and be linked to from the main file.

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Emacs 24.4 Draws Nigh

Not quite in time for Christmas but a new Emacs is coming our way. Stefan Monnier has announced the feature freeze for Emacs 24.4 on the emacs-devel list. I am hearing that things are pretty much working now so if you like life on the bleeding edge, grab the latest distribution and join the fun.

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Tor Best Practices

Over at Digital Era there’s a nice post on Tor best practices. While the Tor protocol and software are reasonably secure, you can’t use them blindly. The most recent example of what happens when you do is demonstrated by Eldo Kim who used Tor and Guerrilla Mail to send a bomb threat to Harvard University. Kim sought to use the bomb scare to avoid taking a final. Unfortunately for him he used the Harvard WiFi network and his identity was discovered simply by checking who on the network was using Tor at the time the email was sent.

It wasn’t a weakness in Tor but Kim’s lack of operational security that caused his discovery. The post at Digital Era helps you avoid errors like Kim’s by explaining how best to use Tor and what practices are dangerous and should be avoided. One of those practices is to never use Tor from or near home. It’s too bad for Kim that he didn’t read that before sending his email.

Most of us aren’t using Tor to send bomb threats, of course, but it is used by many—journalists and activists come to mind—in conditions that could be life threatening if their identities were discovered. If you’re using Tor under conditions that could result in dire consequences should your identity be discovered, you should definitely take a look at the best practices post.

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Git Bisect

Over at randyfay.com, Randy Fay has a great screencast on debugging with git bisect. If you’re not familiar with git’s bisect command, the idea is to find the git commit that introduced an error.

The process is basically a binary search. You have a commit with the error and find one without the error. Now you have the guilty commit bracketed and find it by dividing the commit space in half to find a new bracket end point, just as with a binary search. You could do that by hand, of course, but git partially automates the process with the bisect command.

The process is harder to describe than it is to do. Watch Fay’s screencast to see the bisect command in action. Fay uses git from the command line instead of magit or some other interface so you don’t have to be an Emacs user to profit from the video. If you are an Emacs user, magit has an interface to the bisect command so you can have the best of both worlds.

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A Talk with Linus

In June of last year Linus Torvalds held a Q&A session at the Aalto Center for Entrepreneurship. It’s a far reaching and interesting talk. Torvalds talks about tool building, the beginning of Linux, how the project is run, why Linux has conquered every domain except the desktop, and many other topics.

Torvalds is an interesting guy and famously blunt in his assessments of people and things. This is the video where Torvalds gives his famous characterization of NVidia as the worst hardware company in the history of Linux. It’s at about the 50 minutes point if you can’t wait.

The video is about an hour and four minutes so plan accordingly. It’s long but worth your time. I found it fascinating.

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Phone Tracking

Matt Blaze over at Exhaustive Search has an interesting post on how law enforcement agencies track phone calls. Blaze is discussing law enforcement targeting individuals in support of criminal investigations not the wholesale dragnet surveillance of the type that the NSA specializes in.

If you’re the type that likes cop shows you’re already familiar with some of these techniques. There’s what Blaze calls the retrospective methods that subpoena call detail records from the phone company. There’s also real time methods where the authorities capture call information as the calls happen. Again, many of these—such as pen registers—are part of popular culture and well known to devotees of police procedurals.

What’s more interesting are the lessor know methods such as tower dumps, 911 pings, and IMSI catchers. Blaze explains what these are and how they work.

While there is some controversy over a couple of these methods—especially the IMSI catchers—most people see these techniques as legitimate investigative tools unlike the highly controversial wholesale surveillance used by the NSA. Still, if you’re concerned about privacy and how the government might, legitimately or illegitimately, track your communications, you will find this post helpful.

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