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We propose a methodology to construct verifiable random functions from a class of identity based key encapsulation mechanisms (IB-KEM) that we call VRF suitable. Informally, an IB-KEM is VRF suitable if it provides what we call unique decryption (i.e. given a ciphertext C produced with respect to an identity , all the secret keys corresponding to identity , decrypt to the same value, even if ) and it satisfies an additional property that we call pseudorandom decapsulation. In a nutshell, pseudorandom decapsulation means that if one decrypts a ciphertext C, produced with respect to an identity , using the decryption key corresponding to any other identity the resulting value looks random to a polynomially bounded observer. Interestingly, we show that most known IB-KEMs already achieve pseudorandom decapsulation. Our construction is of interest both from a theoretical and a practical …