Welcome to Cryptography Stack Exchange
Cryptography Stack Exchange is a question and answer site for cryptographers, mathematicians, computer scientists and others interested in cryptography. It's built and run by you as part of the Stack Exchange network of Q&A sites. With your help, we're working together to build a library of detailed answers to every question about cryptography and cryptanalysis.
We're a little bit different from other sites. Here's how:
Ask questions, get answers, no distractions
This site is all about getting answers. It's not a discussion forum. There's no chit-chat.
Good answers are voted up and rise to the top.
The best answers show up first so that they are always easy to find.
The person who asked can mark one answer as "accepted".
Accepting doesn't mean it's the best answer, it just means that it worked for the person who asked.
Should I use ECB or CBC encryption mode for my block cipher?
ECB is not secure, it leaks information. CBC is better. But if you need random access to your file Use CTR mode.
For more information about Block cipher modes of operation see the Wikipedia article.
Never use ECB! It is insecure.
I recommend an authenticated encryption mode, like EAX or GCM. If you can't use authenticated encryption, use CBC or CTR mode encryption, and then apply a MAC (e.g., AES-CMAC or SHA1-HMAC) to the resulting ciphertext.
Get answers to practical, detailed questions
Focus on questions about an actual problem you have faced. Include details about what you have tried and exactly what you are trying to do.
- Asymmetric and symmetric cryptographic algorithms
- Cryptographic protocols and cryptanalysis techniques
- Entropy and information theory
- Random number generation
Not all questions work well in our format. Avoid questions that are primarily opinion-based, or that are likely to generate discussion rather than answers.
Questions that need improvement may be closed until someone fixes them.
Don't ask about...
- Anything not directly related to cryptography
- Questions that are primarily opinion-based
- Questions with too many possible answers or that would require an extremely long answer
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Your reputation score goes up when others vote up your questions, answers and edits.
As you earn reputation, you'll unlock new privileges like the ability to vote, comment, and even edit other people's posts.
|125||Vote down (costs 1 rep on answers)|
At the highest levels, you'll have access to special moderation tools. You'll be able to work alongside our community moderators to keep the site focused and helpful.
|2000||Edit other people's posts|
|3000||Vote to close, reopen, or migrate questions|
|10000||Access to moderation tools|
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Our goal is to have the best answers to every question, so if you see questions or answers that can be improved, you can edit them.
Use edits to fix mistakes, improve formatting, or clarify the meaning of a post.
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