Encryption is the process of transforming plaintext using a cipher to make it unreadable to anyone except those possessing the key.

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Will double encryption increase the security of cipher vs bruteforce?

Assume I have a function encrypt(mes,key) where mes is the message, and key is the key. The length of key is 64 bits. Last but not least: assume the only way to crack my cipher is a brute-force ...
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Encryption and the “security time decay” of prior encrypted data

This question is on the assumption that any data once encrypted, may (eventually) be decrypted through Brute force (compute power/time) Exploits in the cryptography used Theft of private keys ...
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4answers
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Doubling up or cycling encryption algorithms

I've occasionally read the suggestion to enhance security by either doubling up on encryption algorithms (encrypt a message once with one algorithm, then encrypt the ciphertext again with a different ...
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3answers
937 views

How secure is aSSL (javascript)? Does it effectively mimic SSL?

Some of you may be familiar with the aSSL project, which uses AJAX/PHP to mimic the SSL protocol. It uses RSA 512 or 1024 for the keys, and AES for the actual data. It looks impressive to me in ...
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How would I implement “Broadcast Encryption”?

I have a stream that I want to encrypt for broadcast to 10,000 subscribers. I know I should encrypt this data using a symmetric key; and also intend that this symmetric key will be rotated every 30 ...
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5answers
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Can Skype chat be protected from snooping? Are there safe alternatives?

I use Skype a lot. With all of my clients, staff, contractors and friends, however, the acquisition by Microsoft worries me, as two of my clients are direct MS competitors, and I often work on long ...
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3answers
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When is it appropriate to SSL Encrypt Database connections?

Let's say I have a web server I setup, and then a database server. However, they are communicating locally and are behind firewall. In my opinion, no SSL is needed here right? The only time to use ...
6
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5answers
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How can one secure a password/key in source code [duplicate]

If there is a need for source code to have a password in it, how should this be secured? This is purely an example, but say there is an app that is using an API, and you don't want to expose ...
2
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1answer
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Is hardware based disk encryption more secure that software based?

As a spin-off of my question on "Advice on buying an encrypted disk" -- and in an effort to address the question "how is hardware based disk encryption better?" -- I've started a new question. My ...
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How might the U.K. Government's proposed internet surveillance equipment “bypass” encryption?

http://www.channel4.com/news/black-boxes-to-monitor-all-internet-and-phone-data http://rt.com/news/uk-privacy-internet-freedom-186/ 'Black boxes' will be installed by internet services providers ...
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4answers
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How effective is iPhone 3GS and 4 device-at-rest encryption?

My primary goal is to protect Activesync-based communication from being copied or stolen from an offline device. In that context how effective is iPhone 3GS and 4 encryption?
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1answer
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Security of bcrypt/sha256 key used with AES to encrypt a file

I'm looking to encrypt files using secure hashing and encryption algorithms in Python. Having used bcrypt in the past, I decided to use it for my passphrase calculator, then pass the output through ...
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3answers
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Are the encryptions “broken” with great computing power?

http://www.dwavesys.com/en/pressreleases.html#lm_2011 Lockheed Martin Corporation (NYSE: LMT) has entered into an agreement to purchase a quantum computing system from D-Wave Systems Inc. I'm ...
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1answer
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How do I securely store and retrieve a many-time use key?

I am performing some symmetric database encryption/decryption in .net. I am using a single 256 bit private key. (1) Where do I store this key when not in use? (2) How do I securely retrieve this ...
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5answers
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Compute the AES-encryption key given the plaintext and its ciphertext?

I'm tasked with creating database tables in Oracle which contain encrypted strings (i.e., the columns are RAW). The strings are encrypted by the application (using AES, 128-bit key) and stored in ...
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6answers
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Mysql - two-way encryption of sensitive data (email addresses) outside of Apache, PHP and MySQL

We store user email addresses in our database, like many other websites. While we do take pride in the security measures in place, sometimes "just enough" is just not enough. We've begun looking into ...
3
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1answer
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Are there any holes in this security design?

This design is for transport security between a client and a server. I'm planning on using it for a cloud storage system. I would like it to be secure against you-know-who. I'm trying to prevent the ...
3
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1answer
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Using GPG or PGP for symmetric database encryption/decryption in c#

I am looking to symmetrically encrypt/decrypt information in a database. This info consists of short pieces of information, which need to be individually encrypted when a specific method is called. I ...
2
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3answers
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Without SSL, what vantage point does one need to MITM non-SSL'd HTTP?

OK, so there are two things here: being able to read the content of the requests and responses, and then being able to modify them. The former may depend on the latter, I'm not sure. But basically, ...
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2answers
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ECDSA ciphers and forward secrecy question about key exchange

I have heard that with forward secrecy that the ECDSA ciphers generate different keys for "each session" because they are not dependent on the private key of the server. My question is how is "each ...
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2answers
688 views

How to tell what encryption is being used [closed]

How do you tell encryption algorithm used by reading its output? Here is the one I am trying to figure out Åbd$ý ...
67
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5answers
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How can my employer be a man-in-the-middle when I connect to Gmail? [duplicate]

I'm trying to understand SSL/TLS. What follows are a description of a scenario and a few assumptions which I hope you can confirm or refute. Question How can my employer be a man-in-the-middle when ...
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17answers
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Can we still provide confidentiality when cryptography is outlawed?

In certain jurisdictions, use of cryptography by the private sector is limited: e.g. there are reports that in the UAE and other countries not all of the encryption capabilities of the BlackBerry are ...
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iOS Encryption Details

Following on from this question Does anyone have any details/resources on the technical specifics of how apple implement encryption on their iOS 4.x series devices? The Apple marketing material here, ...
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Why can a Tor exit node decrypt data, but not the entry node?

Me -> Node A -> Node B -> Node C -> destination The documentation on Tor always states that only the exit node C can see plain text data. How is this possible without me talking to Node C ...
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8answers
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Software that encrypts the data before deleting it

I am searching for a software that would encrypt data and then delete it (as opposed to just deleting or wiping). With that, even if the file is recovered, you still have to break the encryption to ...
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Storing sensitive information securely

I know there have been a few questions about this already, but I just wanted to know if anyone can take a look at my design plans to see if there are any gaping security holes. I am in the process of ...
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2answers
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How can I check that my cookies are only sent over encrypted https and not http?

I read a blog post GitHub moves to SSL, but remains Firesheepable that claimed that cookies can be sent unencrypted over http even if the site is only using https. They write that a cookie should be ...
21
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6answers
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How to secure a WiFi network?

What do I have to do to secure a WiFi network? Is there any best practices? I have been recommended to use WPA2 encryption on the router, is that enough? What can I do to improve the security even ...
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2answers
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Strength of WEP, WPA and WPA 2 PSK

I know there are three method for wifi security. What are the relative strengths of the password encryption in WEP, WPA and WPA2 PSK?
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7answers
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Why Say IP Addresses Are Harmless?

Whenever I see someone on the internet ask the question, "Can someone find out my IP Address from my tweets/my tumblr/facebook posts/whatever else", the response I always see is, "Who cares! An IP ...
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Is AES encrypting a password with itself more secure than SHA1?

This isn't really a practical question, but more a question of curiosity. I heard a CS professor recommend stepping up from md5ing passwords not to SHA1, but to AES encrypting the password using ...
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Which SSL/TLS ciphers can be considered secure?

The OpenSSL website provides a long list of different ciphers available for SSL and TLS. My question is, which of those ciphers can be considered secure nowadays. I am especially interested in HTTPS, ...
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How does adding a random serial number improve a certificates' security?

This article says: "Finding collisions is a tricky process, since it requires you to muck with the bits of the public key embedded in the certificate (see this paper for more details). Also, ...
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Definitely safest password storage scheme?

I already asked this on StackOverflow but I was suggested this would be a better suited place and I found no way to "move" the question so I have to copy it. Believe, I know, there are hundreds ...
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8answers
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Are powerline ethernet adapters inherently secure?

I have 2 Zyxel PLA407 powerline adapters. Router is downstairs connected to one adapter, other adapter is upstairs about 30 feet away connected to a desktop. I have a house, not an apartment or ...
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The aescrypt implementation hashes a password 8192 times to generate the key. Is this necessary?

I'm considering encrypting some small files (hundreds of kb apiece) using the aescrypt reference implementation. Looking at the source, it seems that the encryption key is derived from the IV and the ...
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3answers
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Are phone calls on a GSM network encrypted?

When I make a call on my cellphone (on a GSM network), is it encrypted?
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5answers
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Securing a laptop against attacks (article)

I came across this article when looking for ways of hardening my laptop, and this guide seemed extremely thorough. It is perhaps overly paranoid, but it will be good to have a guide I can trust should ...
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5answers
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Can voice chat be spied?

I wonder if voice chat (via public services like yahoo, google talk, skype, etc) is practically secure? Is it possible for the ISP or any middle point? I do not consider hacking the computers, but ...
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4answers
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How would you analyze an image to find out if there are scripts embedded in it?

How would you analyze an image to find out if there are scripts or possible malware embedded in it? What tools / methods to use?
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5answers
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What does “key with length of x bits” mean?

I'd like to know what it means to say "the cryptosystem C uses keys with a length of x bits". I do not understand what the bits length means... doesn't it depend on the encoding? The same word encodes ...
12
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2answers
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What are the differences between MD5, SHA and RSA?

MD5 tools output hexadecimal values. In the same manner, do SHA and RSA together produce a hexadecimal (or any other) output? What are the differences between the MD5, SHA and RSA algorithms?
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Verify Login and Encrypt with PBKDF2

I'm writing a desktop application where I'm using PBKDF2 to generate an encryption key to AES-128 encrypt the config file. The config file contains a crypo-random key that's been used to encrypt the ...
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What Partial Homomorphic Encryption implementations exist and how do I leverage them?

It appears that only Partial Homomorphic Encryption(P.H.E.) is practical for modern day (2011) use. However I'm having difficulty locating libraries (FOSS or otherwise) that enable me to leverage ...
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Flaw in encryption through pseudorandom number stream (from gpg documentation)

I was reading PGP docs and came upon a part written by Phil Zimmermann (PGP's creator) that piqued my curiosity: When I was in college in the early 70s, I devised what I believed was a brilliant ...
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SQL field level encryption, how safe is it?

I am considering encrypting my database and/or encrypting only certain columns in a few tables. Is it worth the time? I mean, how much of a burden would it be on someone if they were to get a hold of ...
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Forced into using a static IV (AES)

We've had to extend our website to communicate user credentials to a suppliers website (in the query string) using AES with a 256-bit key, however they are using a static IV when decrypting the ...
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How can I decrypt data with Java, without hard-coding the key?

I hope this is not a chicken-egg problem or reinventing the wheel but here goes. I have a Java application that needs to access a password protected file (actually during the application startup). The ...
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4answers
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Does symmetric encryption provide data integrity?

Let's say I have one server that encrypts a file with a symmetric key, e.g. AES-CBC, and sends it to clients that decrypt it. Does that provide data integrity when decrypted? Or is it possible for ...