Unconditionally Secure Commitment and Oblivious Transfer Schemes Using Private Channels and a Trusted Initializer

We present a new and very simple commitment scheme that does not depend on any assumptions about computational complexity; the Sender and Receiver may both be computationally unbounded. Instead , the scheme utilizes a \trusted initializer" who participates only in an initial setup phase. The scheme also utilizes private channels between each pair of parties. The Sender is able to easily commit to a large value; the scheme is not just a \bit-commitment" scheme. We also observe that 1-out-of-n oblivious transfer is easily handled in the same model, using a simple OT protocol due to Bennett et al..2].

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