Symmetric vs. Asymmetric Encryption Flashcards
What is Symmetric Encryption?
Uses one key to encrypt and decrypt. Also called “secret key” encryption, as the key must be kept secret from third parties.
What are some pros and cons of Symmetric Encryption?
Pros:
Faster because there is only one key
Cons:
Key exchange leaves the key vulnerable
Pre-shared key
List some Symmetric Encryption methods and some characteristics of them.
Advanced Encryption Standard (AES)
* Strongest
* Block Cipher
* 128-bit, 192-bit, 256-bit variants
Data Encryption Standard (DES) and 3 DES
* Weak
* Block cipher
* 56 bits(DES)
* 112 (2 key)
* 168 bits(3DES)
o 3 keys
Blowfish
* Block Cipher
* Weak
* 64 bit
Rivest Cipher (RC*)
* RC4—Stream cipher
* RC5/RC6 – Block ciphers
What is Asymmetric Encryption?
Allows users to encrypt information using shared keys. Data encrypted with the public key can only be decrypted with a private key.
List some Asymmetric Encryption methods and their characteristics.
RSA (Rivest, Shamir, Adleman)
* One of the Oldest
Diffie-Hellman
* Old standard
* Many Variants
Digital Signature Algorithm (DSA)
* Endorsed by NIST for their Digital Signature
Standard
EIGamal
* Used in GNU Privacy Guard, Pretty Good
Privacy
What is a Digital Signature?
A process that uses a public key algorithm (asymmetric encryption) to generate two keys, creating a mathematically linked pair of keys: one private and one public.
Explain the process for how a Digital Signature is used to verify identity.
A hashing algorithm is used to create a hash value then encrypts it with the private key. It then sends the hash value to someone who has a public key. The public key can then be used to decrypt and verify the identity of the person who has the private key.
What is a Cipher Suite?
Sets of instructions that enable secure network connections through Transport Layer Security (TLS). Behind the scenes, these cipher suites provide a set of algorithms and protocols required to secure communications between clients and servers.
