MAC With Partially Cooperating Encoders and Security Constraints
The authors study a special case of Willems's two-user multiaccess channel with partially cooperating encoders from security perspective. This model differs from Willems's setup in that only one encoder, Encoder 1, is allowed to conference, Encoder 2 does not transmit any message, and there is an additional passive eavesdropper from whom the communication should be kept secret. For the discrete memoryless case, they establish inner and outer bounds on the rate-equivocation region. Furthermore, they show that these bounds coincide in the case of perfect secrecy, and so they characterize fully the secrecy capacity.