We present a new anonymous communication channel based on MIXes. The channel is such that faulty nodes can be identified and removed without violating the untraceability of the users, under the assumption that at least a single mix is honest and networking delays are bounded.
Our protocol has three phases, a key sharing phase, a commitment phase, and a sending phase. Once the first two phases are completed, the sending phase can be repeated to send multiple messages.
Our system has the advantage of being computationally more efficient than existing fault-tolerant cascades, in which each MIX has to perform in the order of 50 exponentiations per sender. On the other hand, the protocol presented here lacks a provision for fault compensation without restarting the protocol.
Our scheme makes use of the most basic cryptographic primitives, namely hash functions, signatures, and shared and public key encryptions.
By: Ceki Gulcu
Published in: RZ3125 in 1999
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