CAREER: Anonymous and Robust Multi-Recipient Communication: Foundations and Applications

内容分发是密码技术的一个重要应用领域。 现有的多接收方通信的安全解决方案，如广播加密，主要集中在内容发起者的关注。 该项目从更广泛的角度来解决这个问题，包括接收者的隐私问题，并为内容分发开发加密模型和协议，提供超越数据保密的保证。这项研究的成果将有助于解决与云存储相关的隐私问题。在研究过程中开发的技术将激励密码学和信息隐藏社区的研究人员，从而可能促进各领域之间的合作。该项目有四个具体的研究目标：（1）设计接收方匿名广播加密的密码结构，使其既能提供传输保密性，又能为接收方提供匿名性，并具有与标准广播加密相当的性能;（2）探讨接收者匿名性与密文歧义性之间的关系，它指的是给定的密文可能对多个解密者看起来有效的可能性;（3）广播隐写术的概念的形成，使得能够使用广播信道作为隐蔽通信的媒介;以及（4）对像协作远程存储这样的应用的研究，其中一组用户私下地和不经意地访问云中的共享内容。

Content distribution is an important application domain for cryptographic techniques. Existing security solutions for multi recipient communication, like broadcast encryption, focus mostly on the concerns of the content originator. This project tackles the problem from a broader perspective that includes the privacy concerns of the recipients, and develops cryptographic models and protocols for content distribution that provide guarantees beyond the mere secrecy of the data. The outcomes of this research will enable solutions that address the privacy issues associated with cloud storage. The techniques developed in the course of the research will be stimulating for researchers across the cryptography and information-hiding communities, thus potentially fostering collaborations between the fields. The project has four specific research objectives: (1) the design of cryptographic constructions for receiver-anonymous broadcast encryption that at once provide transmission secrecy, afford anonymity to the receivers, and enjoy performance comparable to standard broadcast encryption; (2) the exploration of the relationship between receiver anonymity and ciphertext ambiguity, which refers to the possibility that a given ciphertext might appear valid to multiple decryptors; (3) the formulation of the concept of broadcast steganography to enable the use of a broadcast channel as a medium for covert communication; and (4) the investigation of applications like collaborative remote storage, whereby a group of users accesses shared content in the cloud privately and obliviously.