Mesh Messaging in Large-Scale Protests: Breaking Bridgefy

Albrecht, M.; Blasco, Jorge; Jensen, Rikke Bjerg; Mareková, Lenka

doi:10.1007/978-3-030-75539-3_16

Cited by 13 publications

(12 citation statements)

References 13 publications

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“…For example, consider a group of protesters split across two physical locations, and assume that devices at each location are able to communicate (e.g. via a mesh network such as Briar [10] or Bridgefy [1]), but that long-range communication between the locations is interrupted (perhaps due to an adversary). This is known as a network partition [19].…”

Section: Goals and Assumptionsmentioning

confidence: 99%

“…The MLS protocol, mentioned in Section 1, uses the TreeKEM key agreement protocol [5,8]. Adding or removing a group member, or performing a PCS key update, requires broadcasting a message of All but last can be concurrent 1 Costs are the number of public-key cryptographic operations performed. The total size of messages broadcast equals the "Sender" column except for Sender Keys and Matrix, which have total broadcast network cost 𝒪(n 2 ).…”

Section: Related Workmentioning

confidence: 99%

“…Anonymity networks such as Tor [16] or Loopix [33] rely crucially on the assumption that no single node is able to observe all network traffic. Protesters use mesh networks, in which mobile devices exchange messages without any servers, to avoid censorship [1,4,38]. In systems such as these, a protocol that assumes a central node or consensus cannot be used, because it would defeat the purpose of the underlying network's decentralization.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Key Agreement for Decentralized Secure Group Messaging with Strong Security Guarantees

Weidner

Kleppmann

Hugenroth

et al. 2021

Proceedings of the 2021 ACM SIGSAC Conference on Computer and Communications Security

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Secure group messaging protocols, providing end-to-end encryption for group communication, need to handle mobile devices frequently being offline, group members being added or removed, and the possibility of device compromises during long-lived chat sessions. Existing work targets a centralized network model in which all messages are routed through a single server, which is trusted to provide a consistent total order on updates to the group state. In this paper we adapt secure group messaging for decentralized networks that have no central authority. Servers may still optionally be used, but they are trusted less. We define decentralized continuous group key agreement (DCGKA), a new cryptographic primitive encompassing the core of a decentralized secure group messaging protocol; we give a practical construction of a DCGKA protocol and prove its security; and we describe how to construct a full messaging protocol from DCGKA. In the face of device compromise our protocol achieves forward secrecy and post-compromise security. We evaluate the performance of a prototype implementation, and demonstrate that our protocol has practical efficiency. CCS CONCEPTS• Security and privacy → Key management; Distributed systems security.

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Section: Goals and Assumptionsmentioning

confidence: 99%

Section: Related Workmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Key Agreement for Decentralized Secure Group Messaging with Strong Security Guarantees

Weidner

Kleppmann

Hugenroth

et al. 2021

Proceedings of the 2021 ACM SIGSAC Conference on Computer and Communications Security

View full text Add to dashboard Cite

show abstract

“…Initially, we only contacted publicly-known figures in Hong Kong, which led to three initial interviews. We then reached out to potential participants through two local gatekeepers, 3 who shared our contact details and a participant information sheet (PIS) with potential participants. The PIS outlined what participation would involve and how we would protect participant information.…”

Section: Semi-structured Interviewsmentioning

confidence: 99%

“…Finally, most participants had heard about the mesh networking application Bridgefy (see [3]), which according to news reports saw a spike in downloads in Hong Kong in September 2019. However, none had successfully used it: "it just doesn't work" (P7).…”

Section: Disconnected Discontentmentioning

confidence: 99%

Collective Information Security in Large-Scale Urban Protests: the Case of Hong Kong

Albrecht¹,

Blasco²,

Jensen³

et al. 2021

Preprint

Self Cite

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The Anti-Extradition Law Amendment Bill protests in Hong Kong present a rich context for exploring information security practices among protesters due to their large-scale urban setting and highly digitalised nature. We conducted indepth, semi-structured interviews with 11 participants of these protests. Research findings reveal how protesters favoured Telegram and relied on its security for internal communication and organisation of on-the-ground collective action; were organised in small private groups and large public groups to enable collective action; adopted tactics and technologies that enable pseudonymity; and developed a variety of strategies to detect compromises and to achieve forms of forward secrecy and post-compromise security when group members were (presumed) arrested. We further show how group administrators had assumed the roles of leaders in these 'leaderless' protests and were critical to collective protest efforts.

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Jay: A software framework for prototyping and evaluating offloading applications in hybrid edge clouds

et al. 2023

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We present Jay, a software framework for offloading applications in hybrid edge clouds. Jay provides an API, services, and tools that enable mobile application developers to implement, instrument, and evaluate offloading applications using configurable cloud topologies, offloading strategies, and job types. We start by presenting Jay's job model and the concrete architecture of the framework. We then present the programming API with several examples of customization. Then, we turn to the description of the internal implementation of Jay instances and their components. Finally, we describe the Jay Workbench, a tool that allows the setup, execution, and reproduction of experiments with networks of hosts with different resource capabilities organized with specific topologies. The complete source code for the framework and workbench is provided in a GitHub repository.

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Mesh Messaging in Large-Scale Protests: Breaking Bridgefy

Cited by 13 publications

References 13 publications

Key Agreement for Decentralized Secure Group Messaging with Strong Security Guarantees

Key Agreement for Decentralized Secure Group Messaging with Strong Security Guarantees

Collective Information Security in Large-Scale Urban Protests: the Case of Hong Kong

Jay: A software framework for prototyping and evaluating offloading applications in hybrid edge clouds

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