Questions tagged [encryption]

Encryption is the process of transforming plaintext using a cipher to make it unreadable to anyone except those possessing the key.

Encryption is the process of transforming information (referred to as plaintext) using an algorithm (called cipher) to make it unreadable to anyone except those possessing special knowledge, usually referred to as a key.

The result of the process is encrypted information (in cryptography, referred to as ciphertext). In many contexts, the word encryption also implicitly refers to the reverse process, decryption (e.g. “software for encryption” can typically also perform decryption), to make the encrypted information readable again (i.e. to make it unencrypted).

source Wikipedia:

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RSA vs. DSA for SSH authentication keys

When generating SSH authentication keys on a Unix/Linux system with ssh-keygen , you're given the choice of creating a RSA or DSA key pair (using -t type ). What is the difference between RSA and DSA keys? What would lead someone to choose one over…
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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 confused as to how this could be possible. Sure,…
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What are ssh-keygen best practices?

Most users would simply type ssh-keygen and accept what they're given by default. But what are the best practices for generating ssh keys with ssh-keygen ? For example: Use -o for the OpenSSH key format rather than the older PEM format (OpenSSH 6.5…
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Is Telegram secure?

There is a new WhatsApp-killer application called Telegram . They said that it's open source and that it has a more secure encryption . But they store all the messages in their servers and WhatsApp doesn't store any messages in any server, only a…
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What is the difference between https://google.com and https://encrypted.google.com?

Is it there any difference between the encrypted Google search (at https://encrypted.google.com ) and the ordinary HTTPS Google search (at https://google.com )? In terms of security what were the benefits of browsing through encrypted Google search?…
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What is the difference between SSL vs SSH? Which is more secure?

What is the difference between SSH and SSL? Which one is more secure, if you can compare them together? Which has more potential vulnerabilities?
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What should you do if you catch encryption ransomware mid-operation?

You boot up your computer one day and while using it you notice that your drive is unusually busy. You check the System Monitor and notice that an unknown process is using the CPU and both reading and writing a lot to the drive. You immediately do a…
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How do mobile carriers know video resolution over HTTPS connections?

Verizon is modifying their "unlimited" data plans. Customers in the USA can stream video at 480p -or- pay to unlock higher resolutions (both 720p and +1080p). They are not the only mobile carrier to implement rules like this . If I am on a site that…
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ECDSA vs ECDH vs Ed25519 vs Curve25519

Among the Elliptic Curve Cryptography (ECC) algorithms available in OpenSSH (ECDH, ECDSA, Ed25519, Curve25519), which offers the best level of security, and (ideally) why?
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How to determine what type of encoding/encryption has been used?

Is there a way to find what type of encryption/encoding is being used? For example, I am testing a web application which stores the password in the database in an encrypted format ( WeJcFMQ/8+8QJ/w0hHh+0g== ). How do I determine what hashing or…
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Why can't the FBI read the key embedded in the iPhone's secure chip/ROM directly from hardware (silicon)?

As far as I understand, the 4 digit passcode is combined (in some fashion) with a key stored in secure read only memory (e.g. secure enclave chip or similar), where it is directly embedded into silicon wiring to help prevent unauthorized reads. But…
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Where to store a server side encryption key?

I have some data that is symmetrically encrypted with a single key in my database. Rather than hard coding it into my code, I am looking for a safer way to store the encryption key. Where can I safely store it?
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Apple's open letter - they can't or won't backdoor iOS?

Apple released an open letter to the public outlining their reasons for not complying with the FBI's demands to modify the iPhone's security mechanism. Here's a summary: The FBI has an iPhone in their possession which they would like to access data…
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Why most people use 256 bit encryption instead of 128 bit?

Isn't 128 bit security enough for most practical applications?
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Do I need to encrypt connections inside a corporate network?

Provided that I have a decent level of physical security in the office, I monitor the physical addresses of devices connected to the network and only give VPN access to trusted parties, do I need to encrypt access to intranet resources over HTTP?…
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