Passwords & hash functions (Simply Explained)
Simply Explained
7 min, 28 sec
The video explains different methods of password protection and the effectiveness of each, including hashing with salt and slowed-down hash functions.
Summary
- The video begins by discussing a website that checks for compromised online accounts and questions the security of passwords.
- It explains three methods of password storage: plain text, encryption, and hash functions.
- The downsides of plain text and encryption are discussed, with emphasis on the superiority of hash functions.
- The concept of hashing with a salt and using intentionally slow hash functions to thwart brute force attacks is explained.
- Dropbox's multi-layer protection method is used as an example of robust password security.
Chapter 1
The video introduces the concept of password security and the problem of compromised accounts.
- The video discusses a website that informs users if their accounts have been compromised.
- It questions whether hackers really know the users' passwords after a breach.
Chapter 2
Explains three methods of storing passwords and their risks.
- Describes plain text storage as dangerous due to vulnerability in case of a data breach.
- Encryption is discussed as an alternative, but it's still risky if the encryption key is also stolen.
- Hash functions are introduced as a one-way, more secure method.
Chapter 3
Delves into hash functions and their one-way property for secure password storage.
- Explains that hash functions convert data into a fixed-length string, providing an example with 'Hello World!'.
- Emphasizes the one-way nature of hash functions, preventing the original data from being retrieved from the hash.
Chapter 4
Discusses the vulnerabilities of hash functions, including speed and identical hashes for common passwords.
- Addresses the susceptibility of fast hash functions to brute-force attacks.
- Illustrates the problem of identical hashes for common passwords like 'qwerty'.
Chapter 5
Chapter 6
Details slowed-down hash functions such as bcrypt, scrypt, and argon2 to counter brute force attacks.
- Discusses special hash functions that are intentionally slow to prevent brute force attacks.
- The 'cost' parameter is explained as a means to control the speed of the hashing algorithm.
Chapter 7
Discusses the multi-layer approach to password protection using Dropbox as an example.
- Explains Dropbox's method of using simple hash functions followed by bcrypt and AES encryption.
- Highlights the importance of multi-layer protection to significantly increase the difficulty of cracking passwords.
Chapter 8
Concludes by emphasizing immediate password changes after breaches and the effectiveness of cryptographic security measures.
- Urges changing passwords immediately after a breach, highlighting that hackers may not have actual passwords due to hash functions.
- Encourages understanding the role of cryptography in protecting passwords.