Functional Encryption Algorithm for Communication in Cloud Computing based on Attribute Based Encryption (ABE)

Functional encryption ensures that user can access encrypted data stored over cloud in which the first step is to encrypt the data files {P1, P2,........,Pn) by the data owner using Cipher text policy ABE that result in {C1, C2,........, Cn}. Then upload the encrypted files on a cloud based storage server or on a public cloud. Once the files are uploaded on the cloud the data owner list the prospective users and send all of them an email which contains two links. The first link is to send request to the Server a key as trapdoor to retrieve the encrypted data from the storage server. On the server side the third party which is a trusted party use this email to identify that this is an authorized user and then fetch the encrypted data file. Using the email id as an attribute it decrypt the file and get a function f(Ci) of the encrypted file.