1. Asymmetric Cryptography
   • Key Pair: Uses a pair of keys—one public and one private.
   • Public Key: Used to encrypt messages.
   • Private Key: Used to decrypt messages.
   • Speed: Slower than symmetric cryptography, often by a factor of 100 to 1000.
2. Public Key Algorithms
   • RSA (Rivest, Shamir, & Adleman):
     • Uses one-way mathematical functions involving large prime numbers (trapdoor functions).
     • Applications: Encryption, key exchange, and digital signatures.
   • Diffie-Hellman Key Exchange:
     • Focuses on exchanging secret keys over an insecure medium without exposing the keys.
     • Often used as a foundation for secure communication.
   • El Gamal:
     • Based on Diffie-Hellman, it operates using discrete logarithms.
     • Offers encryption and digital signature capabilities.
   • DSA (Digital Signature Algorithm):
     • The U.S. government’s equivalent of the RSA algorithm.
     • Primarily used for digital signatures.
   • ECC (Elliptic Curve Cryptosystem):
     • Utilizes the mathematical properties of elliptical curves.
     • Requires fewer resources than RSA, making it ideal for low-power devices like mobile phones.
     • Combines both hashing and asymmetric key algorithms (e.g., MD5 & ECC).

These concepts are critical for understanding how asymmetric cryptography enables secure communication, digital signatures, and key exchange in modern cryptographic systems, especially in environments where performance and resource constraints are significant considerations.