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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What is the difference between encrypted data and data sent through an encrypted tunnel

I am looking at different VPN protocols. [1] L2TP does not provide encryption so require IPSec to encrypt the data [2] IPSec tunnel provide encryption to the tunnel What is the difference in terms ...
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522 views

Android application level encryption cracking

We come across Android applications which use the custom encryption. When we proxy the Android phone or emulator, the proxy captures traffic which is unreadable. Is there a known technique to read ...
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987 views

Is it safe to use different derived keys but from the same passphrase for AES CBC encryption followed by HMAC SHA256 hashing?

I am working on a cross platform (JS/iOS/Android) list manager application that persists data through a REST API and I want to ensure that any textual data is properly encrypted on the client side so ...
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3answers
839 views

US export control on open source libraries

I want to ask, is the US export control applicable only to US citizens? E.g. I think Bouncy Castle are Australians. Do use of their library fall into export control regulations? I do not understand ...
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3answers
556 views

How are possible uses for X.509 (SSL) certificates denoted?

X.509 certificates can be used for servers, clients, email, code signing and more applications. http://twitpic.com/6gdxaq indicates that a certificate can have different of these 'capabilities' on it ...
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Is using HMAC to transmit a password OK?

I'm writing a small webapp and I don't want to transmit login passwords as cleartext. As I don't have SSL available I've written a one-time challenge system which sends a random string with the login ...
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3answers
424 views

How Reliably do mail systems transmit Encrypted PDFs

We have an solution design that will be sending Encrypted PDF's to our many clients, who will all be using varied email providers. We have tested the pdf's through the usual cast of internet mail ...
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2answers
1k views

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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3answers
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How would you store a 4 digit pin code securely in the database?

I'm familiar with password hashing, using salts, bcrypt etc. But it doesn't seem like this would work to store a 4 digit pin code since the attacker could try all 10,000 combinations quite quickly. ...
8
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3answers
676 views

Does the SSL encryption strength of a website really matter?

When looking to get an SSL certificate one is presented with a lot of options. For example lets take Network Solutions since they have a nice comparison chart. Immediately there seems to be 4 major ...
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3answers
267 views

Embedded System Communications Security

I am getting ready to start deploying an embedded sensor network that is internet connected (via the cell network) and reports private data on a regular basis back to a central server. Unfortunately, ...
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1k views

What encryption (if any) is used on electronic credit cards?

Out of curiosity: how do electronic Visa/Master Card debit/credit cards with microchips authenticate a transaction? Are they stupid storage for a key which is simply read by a reader or do they ...
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Is it possible to encrypt your Java source code and still have it readable & writable in Eclipse?

I have some Java source code on my laptop that would cause me a great deal of suffering if I were to lose possession of the laptop and the source code were to fall into someone else's hands. Is there ...
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5answers
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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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3answers
1k views

Is TDEA (TripleDES) invulnerable to the weak keys of DES?

The key space of DES includes some keys that are weak, which results in a ciphertext that is extra vulnerable to cryptanalysis. Is TDEA (also known as TripleDES) invulnerable to those weak keys? Or, ...
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4answers
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AES ECB Mode for single block/random data encryption

I need to save random 16 byte keys to a database. To encrypt these keys I currently use AES 128 with ECB Mode (because of smaller data to store, no IV needed), but now I read a lot about ECB being ...
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4answers
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What steps do Gmail, Yahoo! Mail, and Hotmail take to prevent eavesdropping on email?

I would like to ask what happens when an email is sent from gmail, yahoo or hotmail public web email services? I don't understand email protocols in details, but as far as I know email traffic is ...
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5answers
509 views

What should one do when he/she wants to protect him/her home--computer--?

As you know, deleting a file by pressing shift-delete or by using the Trash doesn't mean that the file is unrecoverable. It's data persists on your computer. In day to day life, adversaries use ...
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2answers
704 views

Which encryption algorithms will be used to replace RSA when quantum computers become common? [duplicate]

Possible Duplicate: Are the encryptions "broken" with great computing power? I just wondered which algorithms will be used once quantum computers become common. Are there already ...
194
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13answers
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How is it possible that people observing an HTTPS connection being established wouldn't know how to decrypt it?

I've often heard it said that if you're logging in to a website - a bank, GMail, whatever - via HTTPS, that the information you transmit is safe from snooping by 3rd parties. I've always been a little ...
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1answer
519 views

Any risk in using the same salt for several hashes on a user?

Right now I'm storing a salt and password_hash on the users table (pretty standard stuff). The need arose to get a secure hash of another field for a user. Is there any risk in reusing the same salt ...
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7answers
1k views

Is there any asymmetrically encrypted file system?

Is there a file system providing a directory where everybody can write, but only the directory owner can read the files? In theory it could be done by encrypting using the public key while writing, ...
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2k views

Encryption on mobile phone - myth?

Well, about six months ago I had pleasure to meet Harald Welte and when he talked about m-banking (banking via smartphones) he said that the most people thing it's safe while, in fact, mobile ...
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1answer
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How can I store downloaded video securely to device's sd card?

I want to save videos in my android mobile's SD card securely such no other application or user can use it, outside the application or on any other devices. So for this what can I do? I think about ...
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2answers
1k views

What is the attack tree to intercept traffic on Wimax?

My current understanding is that sniffing traffic on 4G (lets use Wimax and LTE for the purposes of this question) and 3G is not a simple matter and either requires you setting up a fake base station ...
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2answers
701 views

Do Flash memory (SSD) architecture impacts encryption techniques?

I'm working on encryption techniques on SSD's and my question is: does the erase before write architecture of SSD's has anything to do with the encryption technique? What are the problems I might ...
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Is “real salt” the same as “initialization vectors”?

In the question about real vs. fake salt, the answers describe how real salt 'perturbs the encryption algorithm.' I know roughly how initialization vectors work; is this the same concept, or something ...
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How large blocks does AES-cbc use with a 128 bit key and with a 192-bit key?

I read on wikipedia that the AES with cipher block chaining and a 128-bit key uses blocks of size 128 bit to encrypt the data. However, it also said that with a 192-bit key, there were still 128-bit ...
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3answers
724 views

Server to server encryption: Key rotation over the air. Can it improve security?

In my other question, I explored whether to write my own encryption or use an existing one. I was advised to use TLS or AES or something that is established. This question is about key rotation. It ...
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Smartphone / GSM Sniffer

This question would be in the category of SmartPhone Sniffers. So we have sniffers that can show the packets that are being sent across a wired or wireless (802.11) network. I am just performing a ...
4
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1answer
771 views

Which encryption algo should be best for an Android application [duplicate]

Possible Duplicate: Which type of encryption algorithms android supports, and which would be better? I am confused about to use of DES. Triple DES, RSA and AES algorithms, I think I ...
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875 views

Can a Firefox add-on or plug-in access the user's websites' saved passwords in decrypted mode?

Going deeper into the previous question on Firefox plugins and add-ons malware risks: Could a Firefox add-on potentially decode and capture the encrypted websites' passwords saved in the browser?
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Native rsync protocol security

Is the native rsync protocol (port 873) secure? Does it encrypt data or credentials? I'm planning on using rsync to store encrypted files in the cloud, I'm wondering whatever the password is ...
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Am I wrong to believe that passwords should never be recoverable (one way hash)?

I recently forgot my password for our cable provider online account, only to discover that they sent it to us via plain text in an email. I quickly sent an email to customer support asking them if ...
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8answers
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Is Steganography a safe method to store secret data?

I want to put some parts of my secret data into specific file with Steganography method. Is this method as safe as other encryption methods like RSA or SHA?
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3answers
990 views

AES for key encryption

Is AES a good choice for protecting a key stored on the computer of a user of my application? I have seen threads on hashing passwords that suggest using slow algorithms for defending against brute ...
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1answer
1k views

RSA Key Pair generation with Javascript

I need to generate a RSA key pair with Javascript. This key pair will be used for encrypting a one time blob of data (20-100kb), then discarded. This data can be reduced to a couple of hundred kb or ...
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2answers
440 views

NSA crypto Suite B - historical

I'm looking for information on what NSA suggested for use in commercial systems in past times. 90's and early 2000's. I'm mainly interested in PKI and symmetric cyphers for SSL and file/disk ...
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3answers
6k views

What password-based encryption to use with standard Java 6?

Which password-based encryption method should I use in Java 6? It should be as strong as possible, but work with the default security policy file (not the export restricted one which you have to ...
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7answers
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How can I determine the encryption strength of an SSL connection

If I've connected to a https url, how can I determine the cipher strength of the connection? My understanding is that after the asymmetric public-key handshake the information is encrypted using a ...
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1answer
502 views

Is this security/encryption scheme secure?

I'm rolling my own, personal threetags.com-style 'encrypted data in the cloud' webapp (I didn't like the UI, and lack of non-browser client). However, I have absolutely no experience with security ...
7
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2answers
2k views

SSL Session resumption and IDs

Some sites, as seen in the report for www.mbank.com.pl [ssllabs.com] or report for aliorbank.pl [ssllabs.com] do not support "Session resumption", either because IDs are assigned but not accepted ...
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2answers
4k views

Is 1024bit Diffie Hellman key exchange secure?

My system uses AES-256, 4096bit RSA CA key and 2048bit RSA keys for servers together with SHA-256 signing. Does using 1024bit DH key exchange lower its security? I read on one mailing list that ...
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2answers
2k views

Which cipher suites with AES cipher provide forward secrecy?

Does standard AES with RSA (reported by Opera as TLS v1.0 256 bit AES (1024 bit RSA/SHA)) provide perfect forward secrecy? Which SSL3.0 and TLS1.0 ciphers do provide forward secrecy? Which ciphers ...
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2answers
748 views

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 ...
2
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4answers
459 views

Hash/Digest of string; multiple clients and reverse lookup must be impossible

Ok so i need a technique (could be a system or just an algorithm) to generate a hash/digest of a string on a client app without me (admin of a server app) being able to determine what the original ...
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6answers
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How secure is a Windows password protected zip file?

I need to send some sensitive information to a client. I thought I would email a password protected zip file I created using Windows XP and then call them with the password. Presuming I pick a good ...
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3answers
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Which type of encryption algorithms android supports, and which would be better?

I read this documentation, and I have written an algo to encrypt and decrypt a string. But I don't know how many types of algorithms android supports. Regarding DES and AES (As wiki documentation) ...
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2answers
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What are private key cryptography and public key cryptography, and where are they useful?

I don't understand the real world usage scenarios of these cryptography methods. Can any one please explain how they work, with examples and also their usage in the real world?
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Encrypting data by parts vs encrypting the whole data

Suppose I have a file with records, and I have two options to encrypt it: encrypt the file as a whole encrypt each record separately and store them together. Which way is generally preferable and ...