80-bit vs 128-bit security in today's world In today's world of applications, I see a lot of the time a 256-bit encryption key is used, but what about an 80 or 128? What makes 256 the one to use. Is a 80 or 128 easily decrypted?
Are comp ciphers better than others with the encryption of these keys?
80-bit
First, note that the Bitcoin miner's hash rate reached $&gt; 2^{93}$ SHA-256 hashes per year in February 2021. This makes the 80-bit security absolute for known entities. They even passed that years ago (that is around 2012 per year). And even around 2011, it was absolute and NIST increased security strength from 80 to 122 for Federal Government in 2014. So there is no place for 80-bit in today's security.
128-bit
For 128-bit the question a bit more interesting, while yet there cannot be a group that can reach $2^{128}$ complexity ($2^{35}$-year is needed for a power like the Bitcoin Miners). There are

multi-target attack
In short; The expected cost of finding a key from $t$ targets is $2^{128}/t$. If you have a billion targets that you will be able to find the first key much lower than 128-bit security. The cost would be below $2^{100}$ and the time would be below $2^{70}$.

quantum-based attacks due to Grover's quadratic speed algorithm on symmetric ciphers. If ever build and if we omit other costs, 128-bit has 64-bit symmetric security on quantum computers.


Or see what can be done to AES-128
256-bit
To mitigate all just use AES-256 (or any 256-bit secure cipher like ChaCha20) and that is already the golden standard by the industry. Brute-force is impossible, multi-target has no meaning, and Grovers's algorithm can just reduce the security to 128-bit. Now we are safe as long as there no breakthrough either in breaking the algorithms or find a new scientific advancement.
112-bit
For lightweight cryptography NIST required at least 112-bit security from the 128-bit key size.