# Which Fully Homomorphic Encryption schemes are fastest?

I want to know which one Fully homomorphic encryption schemes are the best in terms of time to encrypt & decrypt or compare between them ?(Preferred valid link)

• [OT] There aren't any FHE schemes currently in practical use owing to their high inefficiency, if I don't err. – Mok-Kong Shen Sep 23 '16 at 20:21
• Whether something is efficient or inefficient always depends on your point of view. For some applications 1 ms may be slow, for others 10 seconds may be more than fast enough. – Cryptonaut Sep 24 '16 at 17:47
• I want compare schemes in Time or performance between them – Heo Sep 25 '16 at 11:25
• Encrypt and decrypt are usually not the operations we are worried about when it comes to performance with FHE. We are more worried about performance when computing on the ciphertexts. – mikeazo Sep 26 '16 at 13:37
• Extending on mikeazo's comment: Which scheme is best strongly depends on your application. Do you really need fully homomorphic or is somewhat homomorphic enough? Over which field do you represent your problem? For a comparison of some systems take a look at Which Ring Based Somewhat Homomorphic Encryption Scheme is Best?, but be aware that it was written before ia.cr/2016/127 and ia.cr/2016/717 . – Hope that's a start Sep 26 '16 at 16:06

Very recently, there appeared a new library $\Lambda \circ \lambda$ (code can be found here). In Section E.2.2 they provide some performance results for a Somewhat Homomorphic Encryption (SHE) scheme, which allow you to evaluate circuits of a fixed depth. If I read the table (Figure 10) correct, then their encryption needs around 371 ms and their decryption 2.3 ms.