{"title":"Discreet: distributed delivery service with context-aware cooperation","authors":"Ludovic Paillat, Claudia-Lavinia Ignat, Davide Frey, Mathieu Turuani, Amine Ismail","doi":"10.1007/s12243-024-01053-1","DOIUrl":null,"url":null,"abstract":"<p>End-to-end encrypted messaging applications such as Signal became widely popular thanks to their capability to ensure the confidentiality and integrity of online communication. While the highest security guarantees were long reserved for two-party communication, solutions for n-party communication remained either inefficient or less secure until the standardization of the MLS protocol (Messaging Layer Security). This new protocol offers an efficient way to provide end-to-end secure communication with the same guarantees originally offered by the Signal protocol for two-party communication. However, both solutions still rely on a centralized component for message delivery, called the Delivery Service in the MLS protocol. The centralization of the delivery service makes it an ideal target for attackers and threatens the availability of any protocol relying on MLS. In order to overcome this issue, we propose DiSCreet (Distributed delIvery Service with Context-awaRE coopEraTion), a design that allows clients to exchange protocol messages efficiently and without any intermediary. It uses a probabilistic reliable-broadcast mechanism to efficiently deliver messages and the Cascade Consensus protocol to handle messages requiring an agreement. Our solution strengthens the availability of the MLS protocol without compromising its security. We compare the theoretical performance of DiSCreet with another distributed solution, the DCGKA protocol, and detail the implementation of our solution.</p>","PeriodicalId":50761,"journal":{"name":"Annals of Telecommunications","volume":null,"pages":null},"PeriodicalIF":1.8000,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Annals of Telecommunications","FirstCategoryId":"94","ListUrlMain":"https://doi.org/10.1007/s12243-024-01053-1","RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"TELECOMMUNICATIONS","Score":null,"Total":0}
引用次数: 0
Abstract
End-to-end encrypted messaging applications such as Signal became widely popular thanks to their capability to ensure the confidentiality and integrity of online communication. While the highest security guarantees were long reserved for two-party communication, solutions for n-party communication remained either inefficient or less secure until the standardization of the MLS protocol (Messaging Layer Security). This new protocol offers an efficient way to provide end-to-end secure communication with the same guarantees originally offered by the Signal protocol for two-party communication. However, both solutions still rely on a centralized component for message delivery, called the Delivery Service in the MLS protocol. The centralization of the delivery service makes it an ideal target for attackers and threatens the availability of any protocol relying on MLS. In order to overcome this issue, we propose DiSCreet (Distributed delIvery Service with Context-awaRE coopEraTion), a design that allows clients to exchange protocol messages efficiently and without any intermediary. It uses a probabilistic reliable-broadcast mechanism to efficiently deliver messages and the Cascade Consensus protocol to handle messages requiring an agreement. Our solution strengthens the availability of the MLS protocol without compromising its security. We compare the theoretical performance of DiSCreet with another distributed solution, the DCGKA protocol, and detail the implementation of our solution.
由于 Signal 等端到端加密信息应用程序能够确保在线通信的保密性和完整性,因此广受欢迎。长期以来,最高的安全保证一直保留在双方通信中,而 n 方通信的解决方案要么效率低下,要么安全性较低,直到 MLS 协议(消息层安全)的标准化。这一新协议提供了一种高效的端到端安全通信方式,与最初用于双方通信的 Signal 协议提供的保证相同。不过,这两种解决方案仍然依赖于一个集中式的信息传递组件,在 MLS 协议中称为传递服务。递送服务的集中化使其成为攻击者的理想目标,并威胁到依赖 MLS 的任何协议的可用性。为了解决这个问题,我们提出了 DiSCreet(Distributed delIvery Service with Context-awaRE coopEraTion),它允许客户端在没有任何中介的情况下高效交换协议信息。它使用概率可靠广播机制来有效传递信息,并使用级联共识协议来处理需要达成一致的信息。我们的解决方案增强了 MLS 协议的可用性,同时又不影响其安全性。我们将 DiSCreet 的理论性能与另一种分布式解决方案 DCGKA 协议进行了比较,并详细介绍了我们解决方案的实现。
期刊介绍:
Annals of Telecommunications is an international journal publishing original peer-reviewed papers in the field of telecommunications. It covers all the essential branches of modern telecommunications, ranging from digital communications to communication networks and the internet, to software, protocols and services, uses and economics. This large spectrum of topics accounts for the rapid convergence through telecommunications of the underlying technologies in computers, communications, content management towards the emergence of the information and knowledge society. As a consequence, the Journal provides a medium for exchanging research results and technological achievements accomplished by the European and international scientific community from academia and industry.