Overview
Symmetric-key cryptography is the field of cryptographic systems that use the same cryptographic keys. The keys, in practice, represent a shared secret between two or more parties that can be used to maintain a private information link
The main drawback of symmetric-key cryptography, compared to public-key cryptography, is the need for both parties to have access to the same secret key. This means that we need a key exchange protocol
Moreover, each recipient is responsible for securely storing the key. Even if we take every precaution to protect the key, there’s no guarantee that others will do the same