D.W.

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May 16	comment	SHA-1:Is there any mathematical result that gives us the minimum number of 1's in a 160-bit SHA-1 hash output? Adnan, your calculation of the probability in the second half of the question is wrong.
May 16	answered	Generating IV in TLS 1.2
May 16	comment	Generating IV in TLS 1.2 How do you know that it's safe to re-use the same key for encrypting the IV and for CBC encryption? That smells fishy to me. (For instance, in a chosen-nonce chosen-message attack scenario, this smells like it might allow distinguishing attacks.) Superficially, re-using the same key in this way seems like dangerous practice, unless there's a proof of security to demonstrate that nothing can go wrong. Do you know of a proof of security for this construction?
May 16	revised	Generating IV in TLS 1.2 Fix a typo.
May 16	comment	pseudo random sequence and permutation functions Mustafa, welcome to Crypto.SE! May I encourage you to read the FAQ? Note that this site is for concrete, specific questions with a objective answer -- discussions or open-ended requests are considered off-topic for this site. Your question is probably too open-ended to be a good fit for this site as it currently stands, and it may be closed if left in its current state, so you might want to edit it to make it a more specific question, following the guidelines in the FAQ.
May 15	awarded	Nice Answer
May 15	comment	Is there a way to do fair exchange between two parties who don't trust each other? "there has been done very little research in this area" - Not true. There have been tons of papers written on fair exchange protocols. (Google Scholar turns up over 100.) Have you done a literature search? You should.
May 15	awarded	Enthusiast
May 15	revised	Is there a way to do fair exchange between two parties who don't trust each other? added 175 characters in body
May 14	revised	CSPRNG in JavaScript using Audio and Video edited tags
May 14	comment	CSPRNG in JavaScript using Audio and Video "Which mode should I use for AES encryption?" - None of them. Encryption is the wrong primitive here. You want to use a cryptographic PRNG (which may involve hashing low-entropy data, so it might use a hash function); but you really don't want to build one of those yourself, you're better off using a carefully-vetted scheme and implementation built by someone who knows this stuff cold.
May 14	comment	CSPRNG in JavaScript using Audio and Video "Gathering binary data from a webcam/microphone" - This is not a good solution for a web application (written in Javascript, and running in the browser). First, only modern browsers support access to the webcam/microphone from Javascript (without using Flash), but if the user has a modern browser, it'll probably support window.crypto.getRandomValues() too, and in that case you're better off using the latter. Second, even if the browser allows access to webcam/microphone, it'll prompt the user to grant access. Users may be reluctant to grant your website that access; then whatcha gonna do?
May 14	answered	CSPRNG in JavaScript using Audio and Video
May 13	revised	Why is the discrete log problem easy when the exponent comes from a binomial distribution? deleted 66 characters in body; edited tags; edited title
May 13	revised	Why is the discrete log problem easy when the exponent comes from a binomial distribution? added 523 characters in body
May 13	revised	Why is the discrete log problem easy when the exponent comes from a binomial distribution? added 523 characters in body
May 13	reviewed	Approve suggested edit on Now that quantum computers have been out for a while, has RSA been cracked?
May 13	revised	Why is the discrete log problem easy when the exponent comes from a binomial distribution? added 1280 characters in body; added 177 characters in body
May 13	answered	Why is the discrete log problem easy when the exponent comes from a binomial distribution?
May 13	comment	Is there a way to do fair exchange between two parties who don't trust each other? I think you know this, but just to be very explicit: The protocol in this answer doesn't meet the requirement of the original question. If Alice is malicious, she can arrange to learn Bob's message without revealing her own message.