Analysis and Improvements of the Sender Keys Protocol for Group Messaging. (arXiv:2301.07045v2 [cs.CR] UPDATED)

Messaging between two parties and in the group setting has enjoyed widespread
attention both in practice, and, more recently, from the cryptographic
community. One of the main challenges in the area is constructing secure
(end-to-end encrypted) and efficient messaging protocols for group
conversations. The popular messaging applications WhatsApp and Signal utilise a
protocol in which, instead of sharing a single group key, members have
individual \textit{sender keys}, which are shared with all other group members.
The Sender Keys protocol is …

analysis applications area attention challenges community conversations encrypted end end-to-end key keys main messaging popular practice protocol protocols sharing signal single whatsapp