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

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84
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7answers
50k views

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 ...
67
votes
8answers
30k views

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 ...
56
votes
6answers
17k views

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 ...
56
votes
13answers
85k views

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
44
votes
10answers
42k views

Speed of TrueCrypt whole disk encryption

I'm getting a new development laptop soon, and I'm thinking of using TrueCrypt to encrypt the whole disk. What kind of performance drop can I expect? 10%? 30%? More? Also, assuming the workload has ...
42
votes
6answers
24k views

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?
40
votes
18answers
8k views

Can I encrypt data in a way that it can be read normally but can't be copied or edited? [closed]

I want to share my 500 GB hard drive with a friend but I want to encrypt it in a way that all data can be read normally but cannot be copied or edited in any way. Is that possible?
38
votes
1answer
2k views

Short, easy to understand explanation of GPG/PGP for nontechnical people?

Does anyone have a link to a good, but short (1-2 paragraphs) explanation of the benefits of using GPG/PGP signing and encryption for Email focused at non-technical readers? That is, why would someone ...
37
votes
3answers
14k views

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 ...
33
votes
10answers
1k views

Password Cracking Windows Accounts

At work we have laptops with encrypted harddrives. Most developers here (on occasion I have been guilty of it too) leave their laptops in hibernate mode when they take them home at night. Obviously, ...
30
votes
2answers
19k views

How secure are password-protected zip files?

In modern zip utilities like 7zip, you can specify a password when creating a .ZIP file. But, how secure is this? What encryption algorithm(s) are used to secure password-protected zip files?
29
votes
10answers
8k views

Determining if a hard disk has been removed and data copied from it?

Is there a method or a tool that can detect if someone has separated my hard disk from my computer, copied data from it, and returned it back? I want to be sure that no one has done this without my ...
28
votes
10answers
2k views

Encrypted HDD 100% safe?

I guess am a bit of a paranoid ha... anyway i encrypted my HDD with truecrypt using all printable ASCII characters and the password is 64 characters long. It is quite random, certainly no dictionary ...
27
votes
5answers
17k views

How does SSH encryption work?

I've read about generating 2 keys (private and public) on client host and copying the public key to the server host. As I understand it, (correct me if i'm wrong): The server encrypts data with the ...
27
votes
3answers
2k views

Can Google Employees See My Passwords Saved in Google Chrome?

I understand that we are really tempted to save our passwords in Google Chrome. The likely benefit is two fold, You don't need to (memorize and) input those long and cryptic passwords. These are ...
26
votes
2answers
15k views

Best encryption and signing algorithm for GnuPG: RSA/RSA or DSA/Elgamal? [closed]

I have found this relatively old question about whether RSA or DSA is the preferred algorithm for signing and encrypting with GnuPG. When using gpg --gen-key, the two relevant choices are either "RSA ...
24
votes
18answers
16k views

How can clients easily and securely send me passwords?

I often need to get passwords from clients for FTP, SSH, MySQL, Authorize.net, etc. What's an easy way for them to send me passwords securely? Maybe even without them needing a login/password? ...
19
votes
2answers
12k views

Is zip's encryption really bad? [closed]

The standard advice for many years regarding compression and encryption has been that the encryption strength of zip is bad. Is this really the case in this day and age? I read this article about ...
18
votes
4answers
55k views

How to access 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. Hence I ...
18
votes
2answers
6k views

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 ...
18
votes
1answer
751 views

How to make suspend to RAM secure on Ubuntu with full disk encryption (LVM on top of LUKS)?

I'm on Ubuntu 13.04 using full disk encryption (LVM on top of LUKS). I would like to incorporate luksSuspend into the suspend procedure (and later use luksResume) so that I can suspend to RAM without ...
16
votes
6answers
19k views

How to list encrypted files in Windows 7?

I somehow encrypted some files without meaning to, and because of it I can't backup my user folder to Mozy. Is there a way to remove the encryption from all the files or at least find out which one ...
16
votes
12answers
2k views

What is the most practical security method for a home wireless network?

Quoting Ars Technica: Proper wireless network (802.11a/b/g/n) security is quite simply out of reach for most organizations. ... Given that WEP (both 64- and 128-bit), WPA1/2 (PSK), and ...
16
votes
2answers
1k views

Does https encrypt URLs, too?

This is fairly easy. If I go to https://webserver.com/someurl?a=b, will the someurl?a=b part be protected, or just the contents of the site?
15
votes
6answers
8k views

Is https traffic over an unencrypted wireless network secure?

This is something I've wondered for a long time. If I am, say, using Gmail over https, can someone read my IM conversations and emails if I use an unsecured wireless network? I assume that the data ...
15
votes
1answer
1k views

Cross platform Hard Disk encryption?

I would like to encrypt my hard drive so that it requires a password to access it. However features like BitLocker in Windows will only work under Windows, and cannot be accessed from another OS such ...
15
votes
2answers
18k views

TrueCrypt, RIPEMD-160 vs SHA-512 vs Whirlpool

I am encrypting a volume with TrueCrypt. I have decided to use AES as the encryption algorithm, seeing as it is the government standard. But which hash algorithm is better (more secure)? RIPEMD-160 ...
14
votes
5answers
3k views

Why is MD5 still used heavily?

MD5 seems to have well documented vulnerabilities and yet it remains widespread in its usage. Does anyone have any reasons for it remaining a viable option when other alternatives (e.g. SHA-2) seem to ...
14
votes
3answers
9k views

GMail and SSL Encryption - how much is encrypted

It's strangely difficult to find out exactly how SSL works with email, at least insofar as answering my specific question - when I connect to gmail using SSL, I understand that my connected is secure ...
14
votes
3answers
31k views

What does the encryption setting of uTorrent do?

I'm having trouble finding precise information about the encryption setting of uTorrent. From what I understand, it's used to hide the torrent traffic from ISPs so that they cannot make the difference ...
14
votes
6answers
9k views

Wipe RAM on shut down to prevent Cold Boot Attack

My system is encrypted using Full Disk Encryption, i.e. everything except /boot is encrypted using dmcrypt/luks. I am concerned about Cold Boot Attacks, where researchers demonstrated, that content ...
13
votes
1answer
5k views

Mount encrypted HFS in ubuntu

I try to mount an encrypted HFS+ partition in Ubuntu. An older post described quite good how to do it, but lacks the information how to use encrypted partitions. What I found so far is: # install ...
13
votes
2answers
12k views

Using TrueCrypt (software encryption) with an SSD

I use full drive encryption (FDE) w/ TrueCrypt on my laptop. I have a 2nd gen I7 with AES instruction support, so honestly I can't even notice a speed change on the system with it on. My question, ...
13
votes
3answers
5k views

How to mount an encrypted ext3 filesystem under OS X?

I know how to mount an ext3 filesystem in OS X with MacFUSE and fuse-ext2. But how can I mount an encrypted ext3 volume? I have Mac OS X 10.6 "Snow Leopard" running.
12
votes
7answers
13k views

Reading an encfs volume from Windows?

I've been looking into encfs as a solution to encrypt my personal data. However I want to access this data both on Linux and Windows on different machines (synced through Dropbox). So far all Google ...
12
votes
7answers
5k views

Is there any P2P private file storage? [closed]

I would like to upload my private encrypted files to the cloud. However I don't want to rely on a company to do this, such as Dropbox. If I share it on a P2P network (such as using torrents) nobody ...
12
votes
1answer
4k views

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") ...
12
votes
4answers
8k views

How to encrypt a file or directory in Linux?

What's the most popular command to do such things as encrypting a file or directory in terminal in Linux?
12
votes
4answers
39k views

SSH: The authenticity of host <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 ...
12
votes
3answers
9k views

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 ...
11
votes
4answers
2k views

How to encrypt an USB stick?

When storing personal data on a USB stick, data needs to be encrypted to ensure privacy. Regrettably, this is far from easy to do without introducing a lot of overhead; ideally, the whole encryption ...
11
votes
3answers
872 views

How are User files in Windows 7 protected?

I noticed that I cannot access user files from one account across another. However, if someone took my HDD, hooked it up to another computer, would they be able to see the files? Is there a way to ...
11
votes
6answers
2k views

Want an easy to use Linux disk encryption scheme

In the interests of protecting personal info in case a laptop gets stolen, I'm looking for the best way to encrypt a Linux system. Disadvantages of whole disk encryption including swap: Pre-boot ...
11
votes
4answers
14k views

How much will full-disk encryption slow down a netbook?

I've been comfortable using TrueCrypt volumes to protect various sets of files on my computers. But I've gathered there can be more convenience and security to be had be encrypting the full hard disk, ...
11
votes
2answers
3k views

How easy is to crack the following copy protection? [closed]

I am trying to copyprotect some work, which is a bootable SD card booting a linux kernel on ARM device (Raspberry pi). I am using this approach: The approach uses an initrd to mount an encrypted ...
11
votes
9answers
11k views

How good is PDF password protection?

It appears that Word's password protection is not really good, at least until Office 2003, if I read this SU entry correctly. I'm under the impression that Acrobat's PDF password protection should be ...
10
votes
3answers
28k views

How to set password on already existing winrar archive and encrypt it also?

Not when creating new archive, but on existing archive. I would also like to know how to do that in other archiver.
10
votes
3answers
11k views

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).
10
votes
1answer
5k views

How do I fix “WARNING: message was not integrity protected” when using GPG symmetrical encryption?

I've encrypted a file using symmetric encryption like this: gpg --symmetric myfile which results in a file myfile.gpg. Alright. Now let's decrypt the file again: gpg -o myfile --decrypt ...
10
votes
1answer
4k views

How does S/MIME differ from PGP/GPG, for the purpose of signing and/or encrypting email?

In addition to the titular question, are the two technologies compatible? If so, under what circumstances? What are the relative benefits of the two technologies?