Homomorphic encryption is an encryption technique that allows users to perform mathematical operations on encrypted data, without accessing the encryption key. At the same time, it makes sure that this relationship or link between the plaintext and ciphertext is executed in a way that it remains hidden from an outsider. This feature promises data security to enterprises, thereby enabling them to conduct operations safely.
● Partially Homomorphic Encryption(PHE): This type supports only certain mathematical operations such as either addition or multiplication that can be conducted any number of times on encrypted values. A key example is RSA encryption, which uses PHE based on multiplicative operations to secure SSL.
● Somewhat Homomorphic Encryption(SHE): This type allows only select operations, either addition or multiplication, to a certain degree of complexity and only a specific number of times.
● Fully Homomorphic Encryption(FHE): This is highly robust and powerful and allows both addition and multiplication unlimited times. It holds good potential and can do arbitrary computations on your ciphertext. An example of FHE's application is in ensuring cloud computing security. It allows you to pull or use your encrypted data stored in the cloud without requiring the cloud service provider to access the data.
● Enabling data analytics in industries like medicine: It allows encrypted data to be shared across commercial cloud spaces for research and information-sharing while keeping the user or patient-data private. This makes it useful in multiple industries, including medicine, information technology, finance, etc., as users can use the data without decrypting it.
● Transparency and improving security in elections: Researchers are exploring these encryption techniques to find ways to conduct democratic elections with more transparency. An example in this regard is the Paillier encryption which uses only addition and thus can be used to add the votes unbiasedly. These technologies could help significantly in reducing manipulations in voting operations.
● Securing Data in the Cloud: If you have any data stored in encrypted form in the cloud, with homomorphic encryption, you can use and search the data and later decrypt it. This avoids the need to share the decrypted data with the cloud service provider.