[[Encryption| Encryption algorithms]] are based around an *encryption key*, or short a *key*. Everyone in possession of the appropriate key can decrypt a previously encrypted message. Thus, protecting an encryption key is of paramount importance for the security of the communication.
In [[Symmetric Encryption|symmetric encryption]] schemes, the same key is used to encrypt and decrypt a message. here, a central challenge is to distribute an encryption key without having an actual meeting between the parties. While a courier might have been an option a few centuries ago, nowadays, billions of devices need to securely communicate over the internet. This challenge of **key distribution** can be tackled with [[Quantum Technologies|quantum technologies]] in the form of [[Quantum Key Distribution|quantum key distribution]].
An alternative are [[Asymmetric Encryption|asymmetric encryption]] schemes, where the encrypting key is different from the decrypting key.
>[!read]- Further Reading
>- [[Encryption]]
>- [[Quantum Key Distribution]]
>- [[Asymmetric Encryption]]
>- [[Symmetric Encryption]]
>[!ref]- References