|Scenario Task Description=When sending an email, it is incredibly easy to fake (or "spoof") one's email address. For example, try sending yourself an email with a made up identity from https://emkei.cz
In order to be certain of each other's email identity the message needs to be signed cryptographically. You can [[I want to learn about digital signatures | do this yourself]] or learn about existing authentication methods used by some email providers.
}}