We study covert secret key generation over a binary-input two-user multiple access channel with one-way public discussion and derive bounds on the capacity region. Specifically, in this problem, there are three legitimate parties: Alice, Bob and Charlie. The goal is to allow Charlie to generate a secret key with Alice and another secret key with Bob, reliably, secretly and covertly. Reliability ensures that the key generated by Alice and Charlie is the same and the key generated by Bob and Charlie is the same. Secrecy ensures that the secret keys generated are only known to specific legitimate parties. Covertness ensures that the key generation process is undetectable by a warden Willie. As a corollary of our result, we establish bounds on the capacity region of wiretap secret key generation without the covertness constraint and discuss the impact of covertness. Our results generalize the point-to-point result of Tahmasbi and Bloch (TIFS 2020) to the setting of multiterminal communication.

翻译：本文研究二进制输入双用户多址信道下通过单向公开讨论实现隐蔽密钥生成的问题，并推导了容量区域的边界。具体而言，该问题涉及三个合法参与方：Alice、Bob 和 Charlie。目标是在确保可靠性、保密性和隐蔽性的前提下，使 Charlie 能够与 Alice 生成一个秘密密钥，同时与 Bob 生成另一个秘密密钥。可靠性要求 Alice 与 Charlie 生成的密钥相同，Bob 与 Charlie 生成的密钥相同。保密性要求生成的秘密密钥仅能被特定的合法参与方知晓。隐蔽性要求密钥生成过程对看守者 Willie 不可检测。作为我们结论的推论，我们建立了无隐蔽性约束的窃听密钥生成容量区域的边界，并讨论了隐蔽性约束的影响。我们的结果将 Tahmasbi 和 Bloch（TIFS 2020）的点对点结论推广至多终端通信场景。