An Ideal Lattice Based IBE Scheme in the Standard Model

摘要

Under the standard model,an IND-sID-CPA secure IBE (Identity Based Encryption) scheme is proposed,which is based on an improved trapdoor generation function over ring and decisional R-LWE (ring-learning with errors) assumption,thus the hardness of recovering system master key can be reduced to solve the Ideal-SIS (small integer solution) problem,and the attack to the ciphertext is equivalent to solving the SVP (the shortest vector problem) in the worst case on ideal lattice to within a fixed poly(n) factor.Moreover,the proposed scheme has advantages of high encryption and decryption speed and low encryption blowup factor compared with all known IBE scheme from the standard lattice under the standard model.