Schneier on Security
A blog covering security and security technology.
November 2008 Archives
Friday Squid Blogging: Cooking a Humboldt Squid
I thought that large squid were too chewy and not very tasty, but this person cooked a 30-pound Humboldt squid.
Terrorism Survival Bundle for Windows Mobile
Seems not to be a joke.
1941 Pencil-and-Paper Cipher
Fascinating photo and explanation.
FBI Stoking Fear
Another unsubstantiated terrorist plot:
An internal memo obtained by The Associated Press says the FBI has received a "plausible but unsubstantiated" report that al-Qaida terrorists in late September may have discussed attacking the subway system.
Got that: "plausible but unsubstantiated," "may have discussed attacking the subway system," "specific details to confirm that this plot has developed beyond aspirational planning," "attack could possibly be conducted," "it's plausible, but there's no evidence yet that it's in the process of being carried out."
I have no specific details, but I want to warn everybody today that fiery rain might fall from the sky. Terrorists may have discussed this sort of tactic, possibly at one of their tequila-fueled aspirational planning sessions. While there is no evidence yet that the plan is in the process of being carried out, I want to be extra-cautious this holiday season. Ho ho ho.
Victoria's Secret Competition Gets Hacked
Colleges aren't assigning enough homework these days.
In seriousness, it's hard to prevent ballot stuffing in online polls.
New DHS Head Understands Security
This quote impresses me:
Gov. Janet Napolitano, D-Ariz., is smashing the idea of a border wall, stating it would be too expensive, take too long to construct, and be ineffective once completed.
I am cautiously optimistic.
Government Can Determine Location of Cell Phones without Telco Help
Triggerfish, also known as cell-site simulators or digital analyzers, are nothing new: the technology was used in the 1990s to hunt down renowned hacker Kevin Mitnick. By posing as a cell tower, triggerfish trick nearby cell phones into transmitting their serial numbers, phone numbers, and other data to law enforcement. Most previous descriptions of the technology, however, suggested that because of range limitations, triggerfish were only useful for zeroing in on a phone's precise location once cooperative cell providers had given a general location.
Here Comes Everybody Review
In 1937, Ronald Coase answered one of the most perplexing questions in economics: if markets are so great, why do organizations exist? Why don't people just buy and sell their own services in a market instead? Coase, who won the 1991 Nobel Prize in Economics, answered the question by noting a market's transaction costs: buyers and sellers need to find one another, then reach agreement, and so on. The Coase theorem implies that if these transaction costs are low enough, direct markets of individuals make a whole lot of sense. But if they are too high, it makes more sense to get the job done by an organization that hires people.
Economists have long understood the corollary concept of Coase's ceiling, a point above which organizations collapse under their own weight -- where hiring someone, however competent, means more work for everyone else than the new hire contributes. Software projects often bump their heads against Coase's ceiling: recall Frederick P. Brooks Jr.'s seminal study, The Mythical Man-Month (Addison-Wesley, 1975), which showed how adding another person onto a project can slow progress and increase errors.
What's new is something consultant and social technologist Clay Shirky calls "Coase's Floor," below which we find projects and activities that aren't worth their organizational costs -- things so esoteric, so frivolous, so nonsensical, or just so thoroughly unimportant that no organization, large or small, would ever bother with them. Things that you shake your head at when you see them and think, "That's ridiculous."
Sounds a lot like the Internet, doesn't it? And that's precisely Shirky's point. His new book, Here Comes Everybody: The Power of Organizing Without Organizations, explores a world where organizational costs are close to zero and where ad hoc, loosely connected groups of unpaid amateurs can create an encyclopedia larger than the Britannica and a computer operating system to challenge Microsoft's.
Shirky teaches at New York University's Interactive Telecommunications Program, but this is no academic book. Sacrificing rigor for readability, Here Comes Everybody is an entertaining as well as informative romp through some of the Internet's signal moments -- the Howard Dean phenomenon, Belarusian protests organized on LiveJournal, the lost cellphone of a woman named Ivanna, Meetup.com, flash mobs, Twitter, and more -- which Shirky uses to illustrate his points.
The book is filled with bits of insight and common sense, explaining why young people take better advantage of social tools, how the Internet affects social change, and how most Internet discourse falls somewhere between dinnertime conversation and publishing.
Shirky notes that "most user-generated content isn't 'content' at all, in the sense of being created for general consumption, any more than a phone call between you and a sibling is 'family-generated content.' Most of what gets created on any given day is just the ordinary stuff of life -- gossip, little updates, thinking out loud -- but now it's done in the same medium as professionally produced material. Unlike professionally produced material, however, Internet content can be organized after the fact."
No one coordinates Flickr's 6 million to 8 million users. Yet Flickr had the first photos from the 2005 London Transport bombings, beating the traditional news media. Why? People with cellphone cameras uploaded their photos to Flickr. They coordinated themselves using tools that Flickr provides. This is the sort of impromptu organization the Internet is ideally suited for. Shirky explains how these moments are harbingers of a future that can self-organize without formal hierarchies.
These nonorganizations allow for contributions from a wider group of people. A newspaper has to pay someone to take photos; it can't be bothered to hire someone to stand around London underground stations waiting for a major event. Similarly, Microsoft has to pay a programmer full time, and Encyclopedia Britannica has to pay someone to write articles. But Flickr can make use of a person with just one photo to contribute, Linux can harness the work of a programmer with little time, and Wikipedia benefits if someone corrects just a single typo. These aggregations of millions of actions that were previously below the Coasean floor have enormous potential.
But a flash mob is still a mob. In a world where the Coasean floor is at ground level, all sorts of organizations appear, including ones you might not like: violent political organizations, hate groups, Holocaust deniers, and so on. (Shirky's discussion of teen anorexia support groups makes for very disturbing reading.) This has considerable implications for security, both online and off.
We never realized how much our security could be attributed to distance and inconvenience -- how difficult it is to recruit, organize, coordinate, and communicate without formal organizations. That inadvertent measure of security is now gone. Bad guys, from hacker groups to terrorist groups, will use the same ad hoc organizational technologies that the rest of us do. And while there has been some success in closing down individual Web pages, discussion groups, and blogs, these are just stopgap measures.
In the end, a virtual community is still a community, and it needs to be treated as such. And just as the best way to keep a neighborhood safe is for a policeman to walk around it, the best way to keep a virtual community safe is to have a virtual police presence.
Crime isn't the only danger; there is also isolation. If people can segregate themselves in ever-increasingly specialized groups, then they're less likely to be exposed to alternative ideas. We see a mild form of this in the current political trend of rival political parties having their own news sources, their own narratives, and their own facts. Increased radicalization is another danger lurking below the Coasean floor.
There's no going back, though. We've all figured out that the Internet makes freedom of speech a much harder right to take away. As Shirky demonstrates, Web 2.0 is having the same effect on freedom of assembly. The consequences of this won't be fully seen for years.
Here Comes Everybody covers some of the same ground as Yochai Benkler's Wealth of Networks. But when I had to explain to one of my corporate attorneys how the Internet has changed the nature of public discourse, Shirky's book is the one I recommended.
This essay previously appeared in IEEE Spectrum.
EDITED TO ADD (12/13): Interesting Clay Shirky podcast.
The Future of Ephemeral Conversation
When he becomes president, Barack Obama will have to give up his BlackBerry. Aides are concerned that his unofficial conversations would become part of the presidential record, subject to subpoena and eventually made public as part of the country's historical record.
This reality of the information age might be particularly stark for the president, but it's no less true for all of us. Conversation used to be ephemeral. Whether face-to-face or by phone, we could be reasonably sure that what we said disappeared as soon as we said it. Organized crime bosses worried about phone taps and room bugs, but that was the exception. Privacy was just assumed.
This has changed. We chat in e-mail, over SMS and IM, and on social networking websites like Facebook, MySpace, and LiveJournal. We blog and we Twitter. These conversations -- with friends, lovers, colleagues, members of our cabinet -- are not ephemeral; they leave their own electronic trails.
We know this intellectually, but we haven't truly internalized it. We type on, engrossed in conversation, forgetting we're being recorded and those recordings might come back to haunt us later.
Oliver North learned this, way back in 1987, when messages he thought he had deleted were saved by the White House PROFS system, and then subpoenaed in the Iran-Contra affair. Bill Gates learned this in 1998 when his conversational e-mails were provided to opposing counsel as part of the antitrust litigation discovery process. Mark Foley learned this in 2006 when his instant messages were saved and made public by the underage men he talked to. Paris Hilton learned this in 2005 when her cell phone account was hacked, and Sarah Palin learned it earlier this year when her Yahoo e-mail account was hacked. Someone in George W. Bush's administration learned this, and millions of e-mails went mysteriously and conveniently missing.
Ephemeral conversation is dying.
Cardinal Richelieu famously said, :If one would give me six lines written by the hand of the most honest man, I would find something in them to have him hanged." When all our ephemeral conversations can be saved for later examination, different rules have to apply. Conversation is not the same thing as correspondence. Words uttered in haste over morning coffee, whether spoken in a coffee shop or thumbed on a Blackberry, are not official pronouncements. Discussions in a meeting, whether held in a boardroom or a chat room, are not the same as answers at a press conference. And privacy isn't just about having something to hide; it has enormous value to democracy, liberty, and our basic humanity.
We can't turn back technology; electronic communications are here to stay and even our voice conversations are threatened. But as technology makes our conversations less ephemeral, we need laws to step in and safeguard ephemeral conversation. We need a comprehensive data privacy law, protecting our data and communications regardless of where it is stored or how it is processed. We need laws forcing companies to keep it private and delete it as soon as it is no longer needed. Laws requiring ISPs to store e-mails and other personal communications are exactly what we don't need.
Rules pertaining to government need to be different, because of the power differential. Subjecting the president's communications to eventual public review increases liberty because it reduces the government's power with respect to the people. Subjecting our communications to government review decreases liberty because it reduces our power with respect to the government. The president, as well as other members of government, need some ability to converse ephemerally -- just as they're allowed to have unrecorded meetings and phone calls -- but more of their actions need to be subject to public scrutiny.
But laws can only go so far. Law or no law, when something is made public it's too late. And many of us like having complete records of all our e-mail at our fingertips; it's like our offline brains.
In the end, this is cultural.
The Internet is the greatest generation gap since rock and roll. We're now witnessing one aspect of that generation gap: the younger generation chats digitally, and the older generation treats those chats as written correspondence. Until our CEOs blog, our Congressmen Twitter, and our world leaders send each other LOLcats – until we have a Presidential election where both candidates have a complete history on social networking sites from before they were teenagers– we aren't fully an information age society.
When everyone leaves a public digital trail of their personal thoughts since birth, no one will think twice about it being there. Obama might be on the younger side of the generation gap, but the rules he's operating under were written by the older side. It will take another generation before society's tolerance for digital ephemera changes.
BNP Database Leaked
This is a big deal.
British National Party (BNP, a far-right nationalist party) membership and contacts list. 12,801 individuals are represented. Contains contact details and notes on selected party members and (possibly) other individuals. The list has been independently verified by Wikileaks staff as predominantly containing current or ex-BNP members, however other individuals who have donated to the BNP or who have had other contact (not necessarily supportive) with the BNP or one of its fronts may also be represented.
Occupations ascribed to the listed names include teachers, a doctor, nurse, vicar and members of the armed forces.
Seems that the BNP database wasn't hacked from the outside, but that someone on the inside leaked the list.
There's a lot more leaked BNP documents on the Wikileaks website.
Friday Squid Blogging: Preserving Giant Squid
At the Smithsonian:
At the centerof the Smithsonian Institution's National Museum of Natural History's gleaming new Sant Ocean Hall lies a preserved giant female squid -- the arresting, spineless star among the vibrant exhibition's animal specimens. Tentacles menacingly outstretched and seemingly frozen in time, the 24-foot squid embodies humans' fascination with the briny deep. But this squid also symbolizes something else: an ongoing experiment in the chemistry of preservation, without which the Smithsonian's new exhibition would not have been possible.
Also note the terrorism tie-in:
To create the exhibit, the Smithsonian had to work around post-9/11 rules restricting flammable materials, while maximizing the lifelike appearance of the squid for public display. They turned not to formalin or ethanol, but to a new fluorinated chemical called Novec, developed by 3M.
If we give up our preserved giant squids, then surely the terrorists have won.
You might think that a Lego safe would be easy to open. Maybe just remove a few bricks and you're in. But that's not the case with this thing, the cutting edge of Lego safe technology. The safe weighs 14 pounds and has a motion detecting alarm so it can't be moved without creating a huge ruckus.
Online Age Verification
A discussion of a security trade-off:
Child-safety activists charge that some of the age-verification firms want to help Internet companies tailor ads for children. They say these firms are substituting one exaggerated threat -- the menace of online sex predators -- with a far more pervasive danger from online marketers like junk food and toy companies that will rush to advertise to children if they are told revealing details about the users.
It's an old story: protecting against the rare and spectacular by making yourself more vulnerable to the common and pedestrian.
When Sky Marshals Do Bad Things
They're not even close to perfect:
Since 9/11, more than three dozen federal air marshals have been charged with crimes, and hundreds more have been accused of misconduct, an investigation by ProPublica, a non-profit journalism organization, has found. Cases range from drunken driving and domestic violence to aiding a human-trafficking ring and trying to smuggle explosives from Afghanistan.
The meta-problem is that the kind of person who wants to be federal air marshal is the exact kind of person we don't want for the job.
Before 9/11, the Air Marshal Service was a nearly forgotten force of 33 agents with a $4.4 million annual budget. Now housed in the Transportation Security Administration, the agency has a $786 million budget and an estimated 3,000 to 4,000 air marshals, although the official number is classified.
And 3,000 to 4,000 is a lot of people to hire quickly; it's hard to weed out the bad eggs.
Secret German IP Addresses Leaked
The PDF document holds a single paged scan of an internally distributed mail from German telecommunications company T-Systems (Deutsche Telekom), revealing over two dozen secret IP address ranges in use by the German intelligence service Bundesnachrichtendienst (BND). Independent evidence shows that the claim is almost certainly true and the document itself has been verified by a demand letter from T-systems to Wikileaks.
RIAA Lawsuits May Be Unconstitutional
Harvard law professor Charles Nesson is arguing, in court, that the Digital Theft Deterrence and Copyright Damages Improvement Act of 1999 is unconstitutional:
He makes the argument that the Digital Theft Deterrence and Copyright Damages Improvement Act of 1999 is very much unconstitutional, in that its hefty fines for copyright infringement (misleadingly called "theft" in the title of the bill) show that the bill is effectively a criminal statute, yet for a civil crime. That's because it really focuses on punitive damages, rather than making private parties whole again. Even worse, it puts the act of enforcing the criminal statute in the hands of a private body (the RIAA) who uses it for profit motive in being able to get hefty fines.Imagine a statute which, in the name of deterrence, provides for a $750 fine for each mile-per-hour that a driver exceeds the speed limit, with the fine escalating to $150,000 per mile over the limit if the driver knew he or she was speeding. Imagine that the fines are not publicized, and most drivers do not know they exist. Imagine that enforcement of the fines is put in the hands of a private, self-interested police force, that has no political accountability, that can pursue any defendant it chooses at its own whim, that can accept or reject payoffs in exchange for not prosecuting the tickets, and that pockets for itself all payoffs and fines. Imagine that a significant percentage of these fines were never contested, regardless of whether they had merit, because the individuals being fined have limited financial resources and little idea of whether they can prevail in front of an objective judicial body.
Another news story.
Skein and SHA-3 News
There are two bugs in the Skein code. They are subtle and esoteric, but they're there. We have revised both the reference and optimized code -- and provided new test vectors -- on the Skein website. A revision of the paper -- Version 1.1 -- has new IVs, new test vectors, and also fixes a few typos in the paper.
Errata: Version 1.1 of the paper, reference, and optimized code corrects an error in which the length of the configuration string was passed in as the size of the internal block (256 bits for Skein-256, 512 for Skein-512, and 1024 for Skein-1024), instead of a constant 256 bits for all three sizes. This error has no cryptographic significance, but affected the test vectors and the initialization values. The revised code also fixes a bug in the MAC mode key processing. This bug does not affect the NIST submission in any way.
NIST has received 64 submissions. (This article interviews one of the submitters, who is fifteen.) Of those, 28 are public and six have been broken. NIST is going through the submissions right now, making sure they are complete and proper. Their goal is to publish the accepted submissions by the end of the month, in advance of the Third Cryptographic Hash Workshop to be held in Belgium right after FSE in February. They expect to quickly make a first cut of algorithms -- hopefully to about a dozen -- and then give the community about a year of cryptanalysis before making a second cut in 2010.
Lastly, this is a really nice article on Skein.
These submissions make some accommodation to the Core 2 processor. They operate in "little-endian" mode (a quirk of the Intel-like processors that reads some bytes in reverse order). They also allow a large file to be broken into chunks to split the work across multiple processors.
That's exactly what we were trying to do.
EDITED TO ADD (11/20): I wrote an essay for Wired.com on the process.
Schneier for TSA Administrator
It's been suggested. For the record, I don't want the job.
Since the election, the newspapers and Internet have been flooded with unsolicited advice for President-elect Barack Obama. I'll go ahead and add mine.
Although I'd be happy to see either Jim or John with it.
I don't want it because it's too narrow. I think the right thing for the government to do is to give the TSA a lot less money. I'd rather they defend against the broad threat of terrorism than focus on the narrow threat of airplane terrorism, and I'd rather they defend against the myriad of threats that face our society than focus on the singular threat of terrorism. But the head of the TSA can't have those opinions; he has to take the money he's given and perform the specific function he's assigned to perform. Not very much fun, really.
But I'd be happy to advise whoever Obama choses to head the TSA.
The Neuroscience of Cons
The key to a con is not that you trust the conman, but that he shows he trusts you. Conmen ply their trade by appearing fragile or needing help, by seeming vulnerable. Because of THOMAS [The Human Oxytocin Mediated Attachment System], the human brain makes us feel good when we help others--this is the basis for attachment to family and friends and cooperation with strangers. "I need your help" is a potent stimulus for action.
This is interesting. They say that all cons rely on the mark's greed to work. But this short essay implies that greed is only a secondary factor.
Most Spam Came from a Single Web Hosting Firm
Experts say the precipitous drop-off in spam comes from Internet providers unplugging McColo Corp., a hosting provider in Northern California that was the home base for machines responsible for coordinating the sending of roughly 75 percent of all spam each day.
Certainly this won't last:
Bhandari said he expects the spam volume to recover to normal levels in about a week, as the spam operations that were previously hosted at McColo move to a new home.
But with all the talk of massive botnets sending spam, it's interesting that most of it still comes from hosting services. You'd think this would make the job of detecting spam a lot easier.
EDITED TO ADD (12/13): I should clarify that this is not the site where most of the spam was sent from, but the site where most of the spam sending bots were controlled from.
Friday Squid Blogging: Vintage Squid Can Labels
Mostly sardines, but some squid.
Interview with me from Datamation.
Me on Passwords
Reducing the Risk of Human Extinction
Not a threat people think a lot about.
Giving Out Replacement Hotel Keys
It's a tough security trade-off. Guests lose their hotel room keys, and the hotel staff needs to be accommodating. But at the same time, they can't be giving out hotel room keys to anyone claiming to have lost one. Generally, hotels ask to see some ID before giving out a replacement key and, if the guest doesn't have his wallet with him, have someone walk to the room with the key and check their ID.
This normally works pretty well, but there's a court case in Brisbane right now about a hotel giving a room key to someone who ended up sexually attacking the woman who had rented the room.
In civil action launched yesterday, the woman alleges the man was given the spare access key to her room by a hotel staffer.
The article doesn't say what kind of authentication the hotel requested or received.
Watching a Malware Author Work
Using the incremental update feature of pdf files to watch a malware author create his exploit.
Censorship in Dubai
I was in Dubai last weekend for the World Economic Forum Summit on the Global Agenda. (I was on the "Future of the Internet" council; fellow council members Ethan Zuckerman and Jeff Jarvis have written about the event.)
As part of the United Arab Emirates, Dubai censors the Internet:
The government of the United Arab Emirates (UAE) pervasively filters Web sites that contain pornography or relate to alcohol and drug use, gay and lesbian issues, or online dating or gambling. Web-based applications and religious and political sites are also filtered, though less extensively. Additionally, legal controls limit free expression and behavior, restricting political discourse and dissent online.
More detail here.
What was interesting to me about how reasonable the execution of the policy was. Unlike some countries -- China for example -- that simply block objectionable content, the UAE displays a screen indicating that the URL has been blocked and offers information about its appeals process.
The Economics of Spam
Excellent paper on the economics of spam. The authors infiltrated the Storm worm and monitored its doings.
After 26 days, and almost 350 million e-mail messages, only 28 sales resulted -- a conversion rate of well under 0.00001%. Of these, all but one were for male-enhancement products and the average purchase price was close to $100. Taken together, these conversions would have resulted in revenues of $2,731.88 -- a bit over $100 a day for the measurement period or $140 per day for periods when the campaign was active. However, our study interposed on only a small fraction of the overall Storm network -- we estimate roughly 1.5 percent based on the fraction of worker bots we proxy. Thus, the total daily revenue attributable to Storm's pharmacy campaign is likely closer to $7000 (or $9500 during periods of campaign activity). By the same logic, we estimate that Storm self-propagation campaigns can produce between 3500 and 8500 new bots per day.
Of course, the authors point out that it's dangerous to make these sorts of generalizations:
We would be the first to admit that these results represent a single data point and are not necessarily representative of spam as a whole. Different campaigns, using different tactics and marketing different products will undoubtedly produce different outcomes. Indeed, we caution strongly against researchers using the conversion rates we have measured for these Storm-based campaigns to justify assumptions in any other context.
Spam is all about economics. When sending junk mail costs a dollar in paper, list rental, and postage, a marketer needs a reasonable conversion rate to make the campaign worthwhile. When sending junk mail is almost free, a one in ten million conversion rate is acceptable.
Reading a Letter from the Envelope it Was In
Paul Kelly and colleagues at Loughborough University found that a disulfur dinitride (S2N2) polymer turned exposed fingerprints brown, as the polymer reaction was initiated from the near-undetectable remaining residues.
Interview on Nuclear Terror
With Brian Michael Jenkins from Rand Corp. I like his distinction between "terrorism" and "terror":
NJ: Why did you decide to delve so deeply into the psychological underpinnings of nuclear terror?
This is also good:
NJ: How do you break this chain reaction of fear?
Aspidistra was a World War II man-in-the-middle attack. The vulnerability that made it possible was that German broadcast stations were mostly broadcasting the same content from a central source; but during air raids, transmitters in the target area were switched off to prevent them being used for radio direction-finding of the target.
The exploit involved the very powerful (500KW) Aspidistra transmitter, coupled to a directional antenna farm. With that power, they could make it sound like a local station in the target area.
With a staff of fake announcers, a fake German band, and recordings of recent speeches from high-ranking Nazis, they would smoothly switch from merely relaying the German network to emulating it with their own staff. They could then make modifications to news broadcasts, occasionally creating panic and confusion.
German transmitters were switched off during air raids, to prevent them from being used as navigational aids for bombers. But many were connected into a network and broadcast the same content. When a targeted transmitter switched off, Aspidistra began transmitting on their original frequency, initially retransmitting the German network broadcast as received from a still-active station. As a deception, false content and pro-Allied propaganda would be inserted into the broadcast. The first such "intrusion" was carried out on March 25, 1945, as shown in the operations order at the right.
EDITED TO ADD (11/13): Photos here.
Friday Squid Blogging: Squid USB Drive
Anti-Terror Law Mission Creep in the U.K.
First terrorists, then trash cans:
More than half of town halls admit using anti-terror laws to spy on families suspected of putting their rubbish out on the wrong day.
EDITED TO ADD (11/13): A better article on the subject.
The Ill Effects of Banning Security Research
The Indian police are having trouble with SIM card cloning:
Police had no idea that one SIM card could be used simultaneously from two handsets before the detention of Nazir Ahmed for interrogation. Nazir was picked up from Morigaon after an SMS from his mobile number in the name of ISF-IM claimed responsibility for Thursday's blasts in Assam.
So far, not that interesting. There are lots of vulnerabilities in technological systems, and it's generally a race between the good guys and the bad guys to see who finds them first. It's the last sentence of this article that's significant:
The experts said no one has actually done any research on SIM card cloning because the activity is illegal in the country.
If the good guys can't even participate, the bad guys will always win.
U.S. Court Rules that Hashing = Searching
Really interesting post by Orin Kerr on whether, by taking hash values of someone's hard drive, the police conducted a "search":
District Court Holds that Running Hash Values on Computer Is A Search: The case is United States v. Crist, 2008 WL 4682806 (M.D.Pa. October 22 2008) (Kane, C.J.). It's a child pornography case involving a warrantless search that raises a very interesting and important question of first impression: Is running a hash a Fourth Amendment search? (For background on what a "hash" is and why it matters, see here).
P = NP?
People have been sending me this paper that "proves" that P != NP. These sorts of papers make the rounds regularly, and my advice is to not pay attention to any of them. G.J. Woeginger keeps a list of these papers -- he has 43 so far -- and points out:
The following paragraphs list many papers that try to contribute to the P-versus-NP question. Among all these papers, there is only a single paper that has appeared in a peer-reviewed journal, that has thoroughly been verified by the experts in the area, and whose correctness is accepted by the general research community: The paper by Mihalis Yannakakis. (And this paper does not settle the P-versus-NP question, but "just" shows that a certain approach to settling this question will never work out.)
Of course, there's a million-dollar prize for resolving the question -- so expect the flawed proofs to continue.
Duplicating Keys from Photographs
EDITED TO ADD (11/3): Here's the paper.
Understanding Terrorist Behavior
Two items, one short and one long.
The short one: "A Look at Terrorist Behavior: How They Prepare, Where They Strike," by Brent Smith, National Institute of Justice Journal, No. 260, 2008.
The long one: How Terrorist Groups End: Lessons for Countering al Qa'ida, by Seth G. Jones and Martin C. Libicki, RAND Corporation, 2008.
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