What it is: Homomorphic Encryption is an encryption scheme that allows software to perform computations on encrypted data without having access to the unencrypted data. It can also be considered a safety measure when operating on encrypted data in the cloud.
What it does: The inventor of fully homomorphic encryption (FHE), IBM researcher Craig Gentry, likened the system to “one of those boxes with the gloves that are used to handle toxic chemicals.” Operations are performed inside the “encryption box” and data never leaves it.
Why it matters: When a client application needs to operate on encrypted data stored in the cloud, either the cloud server needs access to the secret key, leading to security problems, or the client must download, decrypt, operate, re-encrypt, and upload the data, causing logistical and performance problems that erode many of the advantages of cloud computing. If the cloud data is homomorphically encrypted, the client can operate on it without using a secret key and putting the information at risk.
What to do about it: While homomorphic encryption can technically be used with any data, its greatest impacts will be felt in the healthcare, financial, and AI sectors. Today, the technology is too slow and resource intensive for commercial viability. However, with the cloud becoming increasingly central to modern computing, homomorphic encryption will continue to evolve and eventually become a valuable encryption tool.