a) I did some research and there are two opinions.. some say it cracks in several years and others say it doesn't crack for billions of years USING BRUTE FORCE ATTACK...
I am considering attacks on Two-Key Triple-DES Encryption assuming $2^{32}$ known plaintext/ciphertext pairs (that's a mere 32 of ciphertext) by the method devised by Paul C. van Oorschot and Michael J. Wiener:  (in ), or another published method not requiring significantly more DES computations. As a synthetic information for decision makers, I am looking for an independent estimate of how much time this is expected to require, assuming all the RAM ever built by mankind to that day (of April 2012) was put to full use. Note: I'm purposely not asking when the attack could become feasible using all the RAM ever built by mankind, because estimates on the amount of RAM mankind will build, and when, are less falsifiable. Update: I am not considering cost; neither of RAM, power, logic including DES engines (as long as the number of DES operations remains within $2^{90}$). I am willing to assume that the amount of RAM used, and its effective speed, are the only factors to account for in determining the expected duration of the attack. This is similar to the hypothesis made by the authors of the linked paper, that their attack is limited by the amount (or cost) of RAM used, with all other factors of secondary importance. Update: sadly, nobody dared answer the question and the bounty period is over. Thus  is a first order answer to criticize.
I am trying to determine the size in bytes of the contents in a VARBINARY(MAX) field in SQL Server 2005, using SQL. As I doubt there is native support for this, could it be done using CLR integration? Any ideas would be greatly appreciated. How can I monitor my Samba traffic? Is it ethical to use a textbook required for a class that was easily found online? Find the remainder of $\dfrac{2^{2014}}{7}$   I am new to the modular arithmetic, Any suggestions to solve this question? How to evaluate $\int_{0}^{+\infty}\exp(-ax^2-\frac b{x^2})\,dx$ for $a,b>0$ Print numbered paragraph after title with Biblatex My question is related with Biber and Biblatex (latest versions). I need to quote the number of a paragraph of an old Christian text which is published within a book printed nowadays.   More clearly, I'm working with this Biblatex item (it's in Italian):  @INBOOK{Clemente1984Lettera,   author = {Clemente di Roma},   title = {Lettera di Clemente Romano ai Corinti},   year = {1984},   booktitle = {I Padri apostolici},   editor = {Quaquarelli, Antonio},   location = {Roma},   pages = {41-92},   publisher = {Città Nuova} }   I quote it in a common LaTex file with the BibTex key:  \cite[42]{Clemente1985Lettera}   With a humanistic Biblatex style, the final citation is:  Clemente di Roma, Lettera di Clemente Romano ai Corinti, in "I Padri apostolici", edited by A. Quaquarelli, Roma 1985, p. 42.  Anyway, I need to quote specifically the n. 2 of the letter of Clement, so I have to print this number just after the title "Lettera di Clemente Romano ai Corinti". So, I'd like to have this citation:  Clemente di Roma, Lettera di Clemente Romano ai Corinti, n. 2, in "I Padri apostolici", edited by A. Quaquarelli, Roma 1985, p. 42.  Now, I can find no Biblatex field to store the "n. 2" text, and no way to print it after the title. Of course, I could create a specific item in the bibliographic file in which the title field, or another one which is supposed to follow it, contains the "n. 2" indication. Anyway, this solution is very bad to me, because I should fill my archive with items of specific citations, and not of single titles.  What I'm looking for is what I've already implemented in the Bibfilex citations system (), which is moreover far less powerful that Biber: the possibility to add a pipe in the postnote of a BibTex key to separate a possible indication of a number of a paragraph, to be printed just after the title, from the pages of the volume. So a key like that  \cite[2|42]{Clemente1985Lettera}   should print   Clemente di Roma, Lettera di Clemente Romano ai Corinti, n. 2, in "I Padri apostolici", edited by A. Quaquarelli, Roma 1985, p. 42.  Anybody knows how to do that with Biber and Biblatex?  Thanks. What is the difference between N and N-1 in calculating population variance? I did not get the why there are N and N-1 while calculating population variance. When we use N and when we use N-1?      It says that when population is very big there is no difference between N and N-1 but it does not tell why is there N-1 at the beginning.  Edit: Please don't confuse with n and n-1 which are used in estimating.  Edit2: I'm not talking about population estimation. Typo in First Posts queue If you go to the First Posts review queue, and if there's an answer in the queue and if you hover with your mouse over "No Action Needed", then you get a tooltip "this answers seems to be valid":  But it should be "this answer seems to be valid". “Are” vs. “is” after “parents and the family” How can I take shallow depth of field photos with a point-and-shoot camera? Is there a guideline about when to end expressions with semicolons? 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As mentioned above, the query works fine as static SOQL, just not dynamic:  result = [SELECT Name, Another_Object__r.Name, Another_Object__r.Custom_Field__c FROM Custom_Object__c WHERE Another_Object__r.Custom_Field__c = :filter.deviceType];   It also works in this case:  String deviceType = filter.deviceType; Database.query('SELECT Name, Another_Object__r.Name, Another_Object__r.Custom_Field__c FROM Custom_Object__c WHERE Another_Object__r.Custom_Field__c = :deviceType');   I haven't read about this being a known limitation.  I don't know if I should be using some other syntax/notation in the query -- the dotted notation appears correct.  Time to report a bug?  Thoughts on workarounds other than creating local variables to stand in for each member of the class? Minimal and characteristic polynomial have same set of irreducible factors Let $V$ be a vector space over a field $F$ (not necessarily algebraically closed), and $T:V\rightarrow W$ be a $F$-linear map. If $c(T)$ and $m(T)$ denote the characteristic and minimal polynomial respectively, then I want to show that $c(T)$ and $m(T)$ have the same set of irreducible factors.  I know that the claim is true if $F$ is algebraically closed, because then the two polynomials have the same roots. The typical reasoning one gives when $F$ is not algebraically closed is: Take an algebraic closure of $F$, say $K$, and look at $m(T)$ and $c(T)$ in $K$ to conclude the proof. But as far as I know, the proof that any root of $c(T)$ is a root of $m(T)$ requires the fact that $V$ is a $K$-vector space. But we only know that $V$ is an $F$-vector space. I can't understand how to proceed after this. I am coding a small Python module composed of two parts:   some functions defining a public interface, an implementation class used by the above functions, but which is not meaningful outside the module.   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