What is the Public Key Encryption?

TL;DR

Public key cryptography revolutionized the field in 1976, allowing for secure communication and encryption without the need for in-person key agreements.

Transcript

in 1976 we had a huge breakthrough which was the dawn of modern day cryptography with a paper that came out by a different Hellman Hellman was a professor at Stanford and III was his PhD student and they said it's complicated it's physically complicated to meet and agree on the key maybe we can do something different and somehow communicate in the ... Read More

Key Insights

• 🤩 Public key cryptography revolutionized modern cryptography by eliminating the need for physical key agreements.
• 🤩 Public key cryptography involves sharing a public key for encryption and keeping a private key for decryption.
• 🤩 While public key cryptography is secure, it is computationally expensive compared to symmetric key cryptography.
• 🤩 Public key cryptography is used in various applications, including online banking and e-commerce.
• 🤩 Symmetric key cryptography is faster but requires a secure channel for key distribution.
• #️⃣ Public key cryptography is based on mathematical assumptions that make factoring large numbers computationally expensive.
• 🤩 Public key cryptography is used in the initial setup of secure communication, with a subsequent switch to symmetric key cryptography for efficiency.

Questions & Answers

Q: What was the breakthrough in modern cryptography in 1976?

In 1976, Hellman and his student introduced public key cryptography, allowing for secure communication and agreement on encryption keys in the public domain.

Q: How does public key cryptography work?

Public key cryptography involves sharing a public key with others, who can then encrypt messages using that key. The owner keeps the private key to decrypt the messages.

Q: Why is public key cryptography computationally expensive?

Public key cryptography is based on mathematical assumptions like factoring large numbers, which takes significant computational power and time. This makes it more expensive compared to symmetric key cryptography.

Q: When do we use public key cryptography?

Public key cryptography is used for initial secure communication and key agreement. Once established, systems often switch to symmetric key cryptography for faster encryption and decryption.

Summary & Key Takeaways

• In 1976, Hellman and his PhD student proposed public key cryptography as a way to securely communicate and agree on encryption keys in the public domain.

• Public key cryptography allows for secure communication by sharing a public key with anyone, while the owner keeps the secret key to decrypt messages.

• Public key cryptography is used in various scenarios, such as logging into bank accounts or making purchases online, but it is computationally expensive compared to symmetric key cryptography.