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Questions tagged [encryption]

Encryption is the process of transforming information using an algorithm to make it unreadable to anyone except those possessing special knowledge.

Encryption is used to protect stored data and secure online transactions and communications.

Without a specific piece of information, a key, the message cannot be read. Properly done, encryption should make it impossible to determine anything about the original message without knowledge of the key, even if the algorithm is known.

Common Encryption Algorithms

Other encryption-related tags:

Other Stack Exchange sites that discuss encryption:

2849 questions
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SSH: The authenticity of host can't be established

What does this message mean? Is this a potential problem? Is the channel not secure? Or is this simply a default message that is always displayed when connecting to a new server? I am used to seeing this message when using SSH in the past: I…
Steven Lu
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How to find and remove "spicy" media files from my PC

I have an embarrassing problem: during my younger and wilder days, I used to download a certain type of movie clips and pictures. The combination of youthful foolishness and a couple of beers apparently caused me to put these files in odd places on…
Scott
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How can I use encryption with Gmail?

I'm currently reading Cory Doctorow's novel Little Brother which includes a part about encrypted messaging, and even wrapping messages first in my private key and then your public key. I'd like to play around with that but from what I've googled so…
Torben Gundtofte-Bruun
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How to access a BitLocker-encrypted drive in Linux?

I have a laptop running Windows 7 Ultimate. I have encrypted my drives using BitLocker. Now I have also installed Lubuntu along with Windows. But my encrypted drives are not visible in Linux. How can I fix this?
Suyash Mohan
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90
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7 answers

Compress and then encrypt, or vice-versa?

I am writing a VPN system which encrypts (AES256) its traffic across the net (Why write my own when there are 1,000,001 others already out there? Well, mine is a special one for a specific task that none of the others fit). Basically I want to run…
Majenko
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Which TrueCrypt Algorithm is the safest?

If performance is of no concern, which TrueCrypt algorithm is the safest to use? AES Serpent Triple DES Twofish AES-Twofish AES-Twofish-Serpent Serpent-AES Serpent-Twofish-AES Twofish-Serpent
Amir Rezaei
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5 answers

How to use ssh-rsa public key to encrypt a text?

So, the scenario is: Given I'm Bob, I want to encrypt some message for Alice. The only public key I have is her ssh-rsa id_rsa.pub like this: ssh-rsa…
sikachu
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8 answers

Is TrueCrypt truly safe?

I have been using TrueCrypt for a long time now. However, someone pointed me to a link that described the problems with the license. IANAL and so it really didn't make much sense to me; however, I want my encryption software to be open source — not…
Alfred
66
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1 answer

How do I symmetrically encrypt a file using gpg?

I'm trying to symmetrically encrypt a file using gpg. $ gpg --encrypt --symmetric $MYFILE I enter and re-enter a passphrase, then gpg tells me You did not specify a user ID. (you may use "-r") Current recipients: Enter the user ID. End with an…
dave4420
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What are the correct permissions for the .gnupg enclosing folder? gpg: WARNING: unsafe enclosing directory permissions on configuration file

I don't want to just chmod and run until I get the right answer, nor do I want to run GnuPG as root. The easy fix would be to just set it so that only my user can read it, but I don't think that's the best way. I get the following error when I…
Nathan Basanese
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6 answers

What is better for GPG keys - RSA or DSA?

ssh-keygen defaults to creating RSA keys, but gpg --gen-key prefers DSA/ElGamal. Which one - RSA or DSA - is better for GPG?
u1686_grawity
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Does full-disk encryption on SSD drive reduce its lifetime?

I would assume that a full-disk encryption deployment would introduce additional writes each time the computer is booted up and shut down. Given that solid state disks are considered to have a lower average capacity for writes before failure, can a…
Bill
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3 answers

Simple built-in way to encrypt and decrypt a file on a Mac via command-line?

Are there any built in command-line tools that I can encrypt and decrypt a text file (and provide it some sort of password).
codecompleting
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4 answers

Setting up an encrypted git-repository

Situation Hi, I would like to save data with git, encrypted (on some platform like bitbucket or github). Therefore the question: Question I am looking for different hassle-free ways on: How to set up an encrypted repository on…
gr4nt3d
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How to do rsync-like encrypted backup?

I want to save a backup of my data on a remote server, but never want the backup server to see the data unencrypted. Editing a single file and backing up should not result in everything being encrypted and sent again. The remote server should…
user67194
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