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Single-Use Keys Review

Avoid key reuse if at all possible.

Key Takeaways
  1. Using a key more than once adds security risks. That doesn't mean you should never reuse a key, but you should be aware of the risks.
  2. We can't always use single-use keys, sometimes we need to reuse a key. For example, if two parties need to share a key, they probably can't generate a new key every time they need to use it.
  3. If a key doesn't need to be remembered by a human, you can make it long and random. We only use short, less secure passwords when humans need to remember them.
  4. Humans kind of suck. They make security hard.