Practical Cryptography in Python: Learning Correct Cryptography by Example

© Seth James Nielson, Christopher K. Monson 2019

S. J. Nielson, C. K. MonsonPractical Cryptography in Pythonhttps://doi.org/10.1007/978-1-4842-4900-0_3

3. Symmetric Encryption: Two Sides, One Key

Seth James Nielson¹  and Christopher K. Monson²

(1)

Austin, TX, USA

(2)

Hampstead, MD, USA

 

Symmetric encryption is at the foundation of all modern secure communications. It is what we use to “scramble” messages so that people can only decrypt them if they have access to the same key used to encrypt them. That’s what “symmetric” means in this case: one key is used on both ends of the communication channel, to both encrypt and decrypt messages.

Let’s Scramble!

Unsurprisingly, the villains¹ of East Antarctica are at it again, causing all kinds of trouble for their ...