Schneier on Security
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June 13, 2005
According to Jewish law, Torahs must be identical. When you make a copy, you cannot change or add a single character. That means you can't write "Property of...." You can't add a serial number. You can't make any kind of identifying marks.
This turns out to be a problem when Torahs are stolen; it's impossible to identify that they're stolen goods.
Now there's a method of identifying Torahs without violating Jewish law:
Called the Universal Torah Registry, the system works like this: A synagogue mails in a form with their contact information and the number of Torahs they want to place in the system, and the registry sends back a computer-coded template for each scroll. The 3.5- by 8-inch template resembles an IBM punch card, with eight holes arranged so their position relative to one another describes a unique identification number in a proprietary code.
A rabbi uses the template to perforate the coded pattern into the margins of the scroll with a tiny needle. To keep an enterprising thief from swapping the perforated segment with a section from another stolen scroll in some kind of twisted Torah chop shop, the registry recommends applying the code to 10 different segments of the scroll. Pollack says the code contains self-authentication features that keep a thief from invalidating it by just adding an extra hole in an arbitrary location.
Posted on June 13, 2005 at 1:28 PM
• 33 Comments
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I would think that additions to scripture know no language. So a series of miniature punched holes violates not only the spirit of the prohibition but the word as well. The code makes a scroll unique, not a copy.
Obeying the prohibition and providing good security seem to be mutually exclusive.
You say 'You can't make any kind of identifying marks.', and then say 'well, actually, you can make a set of identifying holes'.
Please make your mind up.
From the article, this is why punctures are allowed:
"The system is legal under a rabbinical ruling issued in the 1980s that says it's kosher to make small perforations in a Torah. "Punctures are already used to sew different panels of the parchment together," explains Rabbi Haber, who entered his synagogue's 14 Torahs into the registry after the 1998 burglary."
Who's stealing Torahs anyway? I mean, it's not like the Giddeon Bible!
Perhaps it should be viewed from a Quantum mech perspective, like fundamental particles, Torahs are indistinguishable... and it has no meaning to determine which 'individual' was stolen
Perforations for sewing the panels together are one thing, perforations as identifying marks are another. In light of the 1980's ruling, such registration marks don't violate the word of the Law, but they certainly do violate the spirit.
The injunction against making marks on the Torah is meant to preserve the sacred content by preventing additions and deletions. The addition of registration marks would imply, this Torah is different than the others. So which is authoritative? This can be easily seen as splitting hairs by many, but in a sacred context this inflexibility has the purpose of conveying an intact scripture to the next generation.
It seems to me that this would have one of same problems as any other additive security feature. Register a Torah, get the punch code, find an unregistered Torah, punch it, and then report it as stolen.
The critical question, which I haven't heard an authoritative answer to yet, is what the purpose of the prohibition really is. Is indistinguishability or anonymity of Torahs one of the goals of the law? That might be plausible if the authors of the law wanted to avoid "our Torah is better than yours!" arguments between congregations, and if it's the case, then Yves Adele Harlow's comment above would seem to apply. It's quite plausible that there could be a tradition that no valid Torah is to be regarded as special compared to other valid Torahs, and if so, any identification system seems problematic. I have no idea whether there actually is any such tradition, though. And "problematic" doesn't have to mean "absolutely forbidden". I could easily see that there could be a ruling that the risk of tempting unscrupulous persons to commit theft (creating temptations for others is definitely a bad thing in Jewish law!) is worse than the risks of a cautiously-applied scroll identification system.
Maybe the purpose just to avoid any possibility that something other than the words of the scripture might be thought to be part of the scripture? (E.g. what sometimes happens with other religious writings, where the original writing is published along with a "commentary" that some readers come to believe has special status comparable to the writing itself.) If that latter is the goal, then it would seem that the identifying-mark-added-as-holes method would be legitimate as long as there's no possibility of the identifying mark being confused with part of the text.
I'd think there ought to be biometric-like identifiers applicable, that would use observations of existing features rather the introduction of new features, and those would seem to raise fewer religious problems. Since the scrolls are handmade from natural materials, there should be plenty of variation in the shapes of individual characters, natural texture of the parchment, etc., which could be recorded for later checking without any deliberate creation of identifying features. Someone on Slashdot even proposed looking at the DNA in the parchment, though I don't know how you'd extract it non-destructively.
torahs are hand-written, and can be quite old, ranging up to quite some hundred years. As such, they can have some value as collectibles.
Also, being hand-written, they are sort of expensive to acquire... and one cannot "stamp" it to uniquely identify a specific torah, since no letters can be added to the manuscript -- anywhere! The underlying idea on the prohibition is to forbid changes to the text, even commentaries (commentaries on the torah are made elsewhere).
As with almost everything else in Jewish life, rabinical authority determines how to interpret the Law (in other words the torah, since 'torah' also means 'law').
One could discuss if the torah we use nowadays has never been changed, but this is beyond the point.
Machon Ot's system does the biometrics-like thing: http://www.ott.co.il/torah_id.html
Which of course raises the question of whether the Torahs themselves violate the spirit of the law by not being completely identical!
Or maybe it's because of the martian puppies.
The reason is irrelevant, at least to us. I believe the real point here is that a novel constraint can be dealt with via a novel solution and that identification can be done with a high tech creation but a low tech application.
Personally I'da gone with radio isotopes, but then I like the idea of new-ku-lur word of god.
Why don't they take pictures of it? Hand writing is always unique, yes? And don't museums take pictures of the borders of paintings, so that they have a record of the fibers in the paper, which helps in identification? These are non-invasive methods, isn't that preferable to punching holes in it?
It doesn't violate the spirit of the law. The spirit of the law is to prevent corruption of the text as it is passed down through the millennia. To be sure of this, you not only cannot make any minor alterations to the text (such as modernising spelling or adding vowel diacritics), you cannot make any other marks that could conceivably be mistaken for text. The given method cannot possibly be mistaken for text, so it falls within the spirit of the law.
However if I had to solve this problem, I would have done something even less obtrusive. I would have considered microphotographs of the skin pores of precisely defined locations, such as inside the first Samekh (a letter with a closed loop) of each chapter. (There are pores because Torahs are only written on parchment derived from the hide of a kosher beast. Fingerprint experts have shown that human pore patterns are unique, presumably the same is true for cattle.)
How about we burn them all, and stop worrying about the whole non-issue?
Security is a non-issue? Why then are you posting here?
What exactly are you referring to when you say "burn them"?
In any case, from a security perspective, reducing the value of an asset through diversification, duplication (backups) or other sensible measures, increases the asset's resiliance to theft and/or destruction and therefore actually lowers risk (risk = asset X vulnerability X threat). Thus, this is a very security relevant discussion and a serious issue.
However, simply destroying an asset itself makes no logical security sense unless there is NO value to begin with, which is rarely, if ever, for the security practicioner to decide.
I should probably add that assets are in fact destroyed to prevent disclosure. So the above comments do not apply equally if the assets in question require strict confidentiality (which definitely is not the case for the most major religions).
Problem: To be useful, the perforations have to be made in places where people know where to look. The thieves, knowing where to look, can pretty easily replace those ten pages with ten replacements--keep in mind that a full scroll has hundreds of pages of parchment, so replacing 10 is almost free compared to the cost a complete scroll (especially when the chop shop has lots of hot scrolls lying around). Each scroll fetches as much as $50,000 in the open market, so the motivation is there to replace ten pages.
One might suggest perforating every page, but there are too many pages. Essentially, the perforations render only that one page unsellable, but the process itself represents too large a fraction of the page's full replacement cost to make it economical, given the episodic nature of the threat.
So this defense is about as effective as underscoring, for the thieves to see, the Torah verse "Thou Shalt Not Steal!"
Just give em all some ePaper and a PDF and be done with it.
A couple of questions,
1, If they accept that the document needs binding by "sewing" why not make the thread carry an identifing code (in the same way exploseves do for instance).
2, As they are hand written then there will be considerable differences in the "white space" in the document, why not use this as the identifing code...
Many years ago, there was a system proposed to show how government papers being leaked by making every copy subtaly different. One aspect was to slightly vary the spacing betweeen words letters paragrahs etc during printing (this was a fore runner of digital watermarking by ten or fifteen years).
Also it has been "rumored" for many many years that the works of the English author Francis Bacon carry a similar sort of code. In fact one of the founders of moder cryptography had gainfull employment at trying to find them,
"Pollack says the code contains self-authentication features that keep a thief from invalidating it by just adding an extra hole in an arbitrary location."
Adding more holes will most certainly remove the link to you as owner. It will only indicate that this torah was stolen.
Just as with serial numbers in cars, if you remove it, it is a sign something smells fishy, but the original owner cannot be traced.
People who do not care if it is a stolen copy or not, do not care about the punctures anyway.
Reminds me of the Stephen Wright quote,
"what if someone broke in an exchanged all the torahs for identical copies?"
Seems to have parallels in idenitifying specific diamonds.
Please don't feed the trolls (@x).
As I recall, a torah is series of sewn together pages. Since the text must be perfect, authors must begin a new page with every mistake, so page length is variable. Doesn't this pattern of sewn pages contain enough data (unrolled, they are very long) that the sequence of page distance is a unique ID? The raw distance data itself would still inform a torah-detective if the thief had replaced some chunks between scrolls, large swaths would still be unique. Doing a complete mix-and-match would be combinatoric and require many scrolls.
"Problem: To be useful, the perforations have to be made in places where people know where to look. The thieves, knowing where to look, can pretty easily replace those ten pages with ten replacements--keep in mind that a full scroll has hundreds of pages of parchment, so replacing 10 is almost free compared to the cost a complete scroll (especially when the chop shop has lots of hot scrolls lying around). "
This is a good argument for always using the same ten pages. No scrolls in the chop shop would have unperforated versions of these pages, once all torahs were marked under this system.
(It's also questionable whether pages are interchangeable between scrolls. I'm not sure that pages begin and end at the same places in different scrolls.)
"Punctures are already used to sew different panels of the parchment together" and "eight holes arranged so their position relative to one another describes a unique identification number in a proprietary code"
Unless there is a unique way to sew the panels why not use the sewing in a way reproducing the perforated punch holes ?
As with any security-related matter ... isnt' the fact that a burglar is able to obtain physical access to the object in question already a sign that security is being focused in the wrong place?
@Dossy: I don't think I agree. If you can significantly reduce the black market for something, theft is a much smaller problem. Many religious facilities don't have the money for serious security. Ensuring that there's nothing of value to be stolen is an extremely reasonable measure. It's just very hard, which is why it's uncommon. The Torah is probably one of the few valuables that nearly 100% of buyers would make a good-faith effort to ensure wasn't stolen - marking of VCRs doesn't work as well because there's a great black market.
I think that detailed photos and other analysis techniques aren't likely to work because they're too hard to look up in a database. With a painting, there's an original and your goal is to compare yours to it. With the Torah, yours could be any one in the database. Pageination is an interesting measure, since it's easy to check.
i can't imagine any self-respecting jewish congregation buying a hot torah. as with any other valuable antique, the seller should be able to provide a provenance, the failure to do this is a red flag. if jewish law says torahs have to be identical, punching unique holes in them seems to be an infraction, but because there is no pope or other supreme authority to tell a jewish congregation what to do, their laws are necessarily subject to local interpretation. i propose that it should be ok for jews to eat pork and shellfish as long as they don't look at it first to ascertain precisely what it is.
@David Cowan: The perforations can be made on an arbitrary set of pages, and the congregation can store a record of which pages were perf'ed in a separate secure location.
@Allan: Each page's content is fixed. If there is a problem with some part of the text, the scribe would repair it in situ if possible or redo that page if not. The content of the pages will not vary from one Torah scroll to another.
@Clive: The exact composition of the thread is also dictated by law & tradition.
The advantage of this method over such things as microphotographs of the parchment's pores is that the scroll and the advanced technological equipment need never be in the same location. This seems to me to improve the ability of implementing this cheaply.
"The advantage of this method over such things as microphotographs of the parchment's pores is that the scroll and the advanced technological equipment need never be in the same location."
Certainly that's an advantage, but I'd also like to point out that in this day and age, microphotography is not particularly advanced technology. Think Geek is currently selling a hobbyist's portable digital microscope which would be ideal; hand-held or stand mounted modes, built in LED lamps, up to 200 x optical magnification, and USB connection to your laptop (stills or video). It only costs USD $80.
ObSecurity: any security techniques which rely on the assumption that microscopy is something done by experts in a lab, had better think again.
Roger suggested the right things. Even being into the subject, I couldn't find any solution better than what Roger has suggested.
However there is a foul proof method called id tor which scans in a couple of pages of the torah into a computer then if a torah is found and it is in id tor system the name of the owner will show on the computer
Torahs can be sold, and there is a market for pre-owned Sefer Torahs, but in most cases since it's synagogues that are buying them, they would come to an organization and try to find out and make sure that it is not stolen
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