Features, applications and implications of encryption

Encryption is a mathematical process which uses an algorithm to convert data into a form which can not be read by any party. In order to retrieve the original data, a ‘key’ is required.

Encryption can be either symmetric (the same key is used to encrypt and decrypt the data), or it can be asymmetric (a different key is used for each part).

Features of encryption

• Data is not viewable by an outside actor
• Only people with the correct key can view the data
• The data is identical after decryption as it is before

Applications of encryption

There are many applications for encryption. Any time sensitive data is stored, processed or transmitted, encryption is used. In addition, any time that users wish for privacy, encryption is used. Some examples are:

• HTTPS (SSL) – data is encrypted between client and server, ensuring that details entered by a user can’t be viewed in transit between the two devices. For example payment details, usernames and passwords
• Messaging services – only the sender and receiver can view the messages. No other party can access the data (e.g. WhatsApp, iMessage)
• Data storage – where sensitive data is stored (e.g. medical), this is encrypted so that if the database is breached, the data is unreadable

Implications of encryption

The rise in encryption has affected hardware design – CPUs now contain dedicated hardware to ensure that there is no performance penalty when encrypting or decrypting data. This is especially important in devices such as laptops, where entire drives are encrypted and must be encrypted or decrypted on the fly, whilst using as little power as possible.

Although users appreciate the security that having their communications encrypted brings, there are big moral and social ramifications of this: law enforcement are unable to read messages sent using these services, and therefore argue that it makes it difficult to intercept criminal activity.

One suggestion would be to build in a ‘back door’ to the encryption (like a special key for law enforcement to use), however this brings its own risks: if a back door exists for ‘good’, it will only be a matter of time before the details are known to malicious parties, and this would likely do more harm than good.