It takes twice as long to break an encryption key for every added bit
There’s an enomous inherent mathematical advantage in encrypting vs trying to break encryption. Fundementally, security is based on the length of a key; a small change in the key length results in an enormous amount of extra work for the attacker. The difficulty increases exponentially. A 64-bit key might take an attacker a day to break. A 65-bit key would take that same attacker twice the amount of time to break, or two days. And a 128-bit key—which is at most twice the work to use for encryption—would take the same attacker 264 times longer, or one million billion years to break. This is why you hear statements like: “This can’t be broken before the heat death of the universe, even if you assume the attacker biuilds some giant computer using all the atoms of the planet.”
References
- Schneier, Bruce. (2015). Data and Goliath The Hidden Battles to Collect Your Data and Control Your World Chapter 11. Security (Location 2302). New York, NY: W. W. Norton & Company.