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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Is Steganography considered encryption and subject to USA export restrictions?

I have written an application for Apple's iOS which embeds messages in JPEG files using steganography (see http://en.wikipedia.org/wiki/Steganography). For the purposes of this question lets assume ...
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Why can an encrypted private key be brute forced?

When using SSH keys to authenticate to a server for remote access, why is it possible to devise the true key and therefore the passphrase from an encrypted private key, without checking each guess of ...
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Encrypting with Mongo

How can I achieve the following goals? All compute and storage to be located in the cloud. Encryption in transit of all data between web nodes and db nodes running MongoDB. How to set up tunnels? ...
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How should passwords be stored if they must be recoverable?

By "encrypting" passwords you are violating CWE-257: Storing Passwords in a Recoverable Format. But this is exactly what the French government wants. They want to be able to obtain the passwords of ...
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Can RSA (or any public/private key algorithm) be repeated for large amounts of data?

I'm working on a small security assignment and I was instructed to implement simple encryption/decryption of files using RSA in C#. When attempting to encrypt/decrypt large files, I was informed by ...
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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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Is there any advantage to splitting a password?

I've been reading about the LANMAN (LM) hash and I'm curious about a particular part of the algorithm. The LM hash is computed as follows: The user’s ASCII password is converted to uppercase. ...
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2answers
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What is the correct way to assess and compare Certicom's products to the alternatives?

I'm investigating Certicom's API because they are "free" with the Blackberry implementations, and have come to realize that I have several alternatives for implementing crypto such as BouncyCastle, ...
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Are there any serious problems with this technique for generating symmetric keys?

I'm using a technique borrowed out of a book by Bruce Schneier and Niels Ferguson called Practical Cryptography. Basically, it boils down to this: Bob does this: pubk_A = Alice's public key ...
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With reference to using Gpg4win, which is better: OpenPGP or S/MIME?

Which is better -- OpenPGP or S/MIME for higher security?
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What is the correct crypto to use for a “Password Wallet”, where decryption of the secret is needed?

I would like to create a shared "password wallet" where I encrypt several instances of a username/password and store it in a common location. I don't expect all key/value pairs to have the same ...
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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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1answer
132 views

Enterprise and Open Cryptographic Systems/Applications?

Please can someone tell me the main Enterprise/Open Cryptographic Systems in use, I am having a hard time googling for them. I know OpenPGP is one, but is that the best and most ubiquitous one for ...
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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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1answer
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How to find out if a connection encrypted?

I'm sniffing a connection that uses ICEP (ZeroC ICE Protocol), and its packet bodies compressed using BZ2 (GNU BZip 2) algorithm. I want to find out whether packets encrypted, or not. ICEP can use ...
3
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1answer
909 views

How to apply FIPS to Microsoft Access database with custom VBA

As the software engineer on a project, I have been asked to make a Microsoft Access application, with custom interfaces running custom VBA. That part is going just fine. Recently though I was asked to ...
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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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Is a large number of RSA-encrypted files a vulnerability?

Would having a large number (10^4) of RSA encrypted files make it easier for an attacker to find my private RSA key? Update: These files would be available to the attacker, and perhaps the content of ...
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Should RSA public exponent be only in {3, 5, 17, 257 or 65537} due to security considerations?

In my project I'm using the value of public exponent of 4451h. I thought it's safe and ok until I started to use one commercial RSA encryption library. If I use this exponent with this library, it ...
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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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Suitable cipher for SMS encryption

I would like to create application for encrypting SMS messages. After long enough discussions I decided to use symmetric encryption, since handling public/private keys issue is too difficult for most ...
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5answers
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What can one do when encryption methods fail?

I'm in search of an expert to answer my curiosity. Suppose that methods like AES/DES, SSH, PGP, RSA, etc. can be cracked or fail somehow. In other words, suppose that it's possible to determine one ...
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What is your process for wiping a lost Blackberry or similar device?

For all devices I know of, if a device is lost or stolen, it needs to be connected to the Cellular network to receive the wipe command. Considering that the end user often needs to regain mobile ...
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Multiple VPN clients in parallel

If I were to run more than one VPN clients on my machine, simultaneously, what risks would be involved? E.g. are there technical conflicts, such that it wouldn't work right? Could there be ...
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1answer
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What is encryption method for the 3rd part of the Kryptos text?

http://fr.wikipedia.org/wiki/Kryptos_%28sculpture%29 http://en.wikipedia.org/wiki/Kryptos I read the Kryptos wikipedia page, is says it's crypted with a "modular transposition of lines and columns". ...
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Why triple DES used in EDE mode?

Why is triple DES is calculated in encrypt decrypt encrypt mode? Why a decrypt in the middle? And isn't decrypt = encrypt since DES in a symmetric cipher?
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Initialization vector with cipher block

Is the initialization vector used to encrypt a block of data always static or dynamic? If it is dynamic then I should send the IV along with the key to the recipient right? This normally doesn't ...
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where can find sample coding for use of Bouncy Castle(java)?

I had found bcprov-ext-jdk16-145.jar and bcprov-jdk16-145.zip. I wish to use the IDEA encryption to encrypt XML, but i haven't found any sample of coding in JAVA. Can anyone tell me how to call the ...
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What kind of encryption is a one-time pad?

Is it a substitution cipher or a stream cipher or both?
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Encryption decryption time

Does the encryption / decryption time of rsa algorithm vary significantly with a change in key length? For example, is there a noticeable difference in encryption/decryption time between 512 bit and ...
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Why should one not use the same asymmetric key for encryption as they do for signing?

In an answer to a question about RSA and PGP, PulpSpy noted this: It is possible to generate an RSA key pair using GPG (for both encryption and signing -- you should not use the same key for ...
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What are the realistic, and most secure crypto for Symmetric, Asymmetric, Hash, Message Authentication Code ciphers?

I'm interested in updating this two pronged question for 2011: What cryptology is most appropriate for low-powered devices (such as a cellphone), and yet still effective? What cryptology is most ...
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Safe implementation of sharing encryption secrets (username, password) in the cloud

I'm building a multi-tenant (cloud) environment that needs to push out (or make available for download) configuration files for agents (background services) that receive this information. One of the ...
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Storing private asymmetric key in application binary?

I would like to give a daemon-style process (i.e. no user interaction) access to a shared secret key so that it can access a shared, encrypted data file. User applications accessing the same encrypted ...
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How can I authenticate a client connection in a secure way?

Let's say I have a server listening on port 1234. I have some client software that needs to be able to connect to this port. But I want to prevent malicious users from bypassing the client software ...
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Which Instant Messaging services use or allow secure protocols, and what do those protocols cover?

We all know there's a myriad of Instant Messaging (IM) services out there. But, which of these services uses or permits protocols that actually secure your communications? For those that do, what ...
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What are the problems with encrypted but unsigned data?

In another question's answer, D.W. wrote: Make sure there is authenticity protection for the encrypted data (e.g., encrypt and then sign/MAC): you will need both confidentiality and authenticity ...
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3DES vs DES for VPN connections

I'm trying to get Android 2.1 phones to connect to our corporate VPN, but it would appear they only support DES rather than 3DES for encryption. Is it safe to use DES, am I going to get hacked if I ...
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Backing up sensitive data - pitfalls and best practices

Obviously, securely backing up sensitive data is a challenge. A remote backup is important for surviving a variety of disasters. What are some of the "gotcha's" lurking out there, and what best ...
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What's the standard way to encrypt a file with a public key in Java?

I'm writing a client app in Java that sends encrypted data back to the server. All clients have my RSA public key. Is there a standard way to encrypt a given file with it to send it back to the ...
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What common products use Public-key cryptography?

I want know what common use products are there that use public key/private key cryptography?
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Copyright issues with encryption algorithms

I'm developing application for Android/Java. Application is a kind of password manager, so I'm storing encrypted passwords under the hood of master password. There are number of encryption algorithms ...
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Securing an E-commerce site

I'm building a custom e-commerce site, and the user will input their credit card details on the site instead of being directed to the payment gateway's site. I'm confused as to what the critical ...
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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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When brute-forcing DES, does knowing something about the plaintext help?

Data Encryption Standard (Wikipedia) I know that with brute force there are 2^56 possible keys to check (56 bits, each either a 1 or 0). But let's say I know the message itself is only made up 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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For users that does not use PGP, what would be the other channel to securely send them a document?

I would like to send a document that is confidential to users that have no clue what PGP is (so no point in teaching them how to install it etc...) via email. The real question is how to do that? ...
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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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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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Encrypting a Database's Primary Key when sent to the browser

When dealing with either an oData-based application (ADO.NET Data Services), or something that otherwise publishes the PrimaryKey, or ForeignKey to the client... Can someone explain to me be benefits ...