Digital Currencies and Blockchain Technology Course 2

发表于 2022-07-06 更新于 2022-07-14 分类于 Course Reviews Disqus：本文字数： 2.6k 阅读时长 ≈ 5 分钟

This course mainly introduces SHA 256 Hash, challenges bitcoin encounters with nowadays, the history of bitcoin.

SHA 256 Hash

SHA-256 is a patented cryptographic hash function that outputs a value that is 256 bits long. In hashing, the probably unlimited sized data will be mapped into smaller size of strings.

Why do the hash, that method that makes the message unrecoverable? The most common reason is to verify the content of data that must be kept secret. For example, hashing is used to verify the intergrity of the secure messages and files. The hash code of a secure file can be posted publicly so users who download the file can confirm they have an authentic version without the contents of the file being revealed. Hashes are similarly used to verify digital signatures.

Password verification is a particularly important application for cryptographic hashing. Strong user’s passwords in a plain-text document is a recipe for disaster; any hacker that manages to access the document would discover a treasure trove of unprotected passwords. That’s why it’s more secure to store the hash values of passwords instead. When a user enters a password, the hash value is calculated and then compared with the table. If it matches one of the saved hashes, it’s a valid password and the user can be permitted access.

SHA-256 is used in some of the most popular authentication and encryption protocols, including SSL, TLS, IPsec, SSH, and PGP. In Unix and Linux, SHA-256 is used for secure password hashing. Cryptocurrencies such as Bitcoin use SHA-256 for verifying transactions.

Information in addition: https://21-ways.com/toc

Challenges for Bitcoins

No space for endless transactions, because of the scaling of the Bitcoin Network
- High transaction fees (at full capacity)
- Slow transfers (at full capacity)
High volatility
High power consumption
Competition from other cryptocurrencies

HODL

HODL ($HODL) is a cryptocurrency that was named based on the popularity of “HODL” as an expression in the crypto community. The HODL token operates using the Binance Smart Chain, and HODL token owners can earn Binance Coin rewards.

https://www.investopedia.com/terms/h/hodl.asp

SHA 256 Hash

Challenges for Bitcoins

HODL

History of Bitcoin

Articles for the Final Presentation

For further exploration