Vuvuzela

[labbe5]

We kill people based on metadata

— Michael Hayden, former Director of the NSA



Metadata absolutely tells you everything about somebody's life

— Stewart Baker, former General Counsel of the NSA


Vuvuzela is a private chat application that hides metadata, including who you chat with and when you are chatting. Vuvuzela supports millions of users and is secure even if the network and a majority of the servers are compromised.

Vuvuzela is built on mathematical foundations. To hide metadata, messages are routed through multiple servers, and each server adds noise. The servers add enough noise to guarantee differential privacy, a formal definition of privacy that enables users to quantify their metadata privacy after sending many messages through the system.

The research powering Vuvuzela is being conducted at MIT CSAIL and has been published in top systems conferences.
Source : https://vuvuzela.io/

Vuvuzela is a messaging system that protects the privacy of message contents and message metadata. Users communicating through Vuvuzela do not reveal who they are talking to, even in the presence of powerful nation-state adversaries. Our SOSP 2015 paper explains the system, its threat model, performance, limitations, and more. Our SOSP 2015 slides give a more graphical overview of the system.

Vuvuzela is the first system that provides strong metadata privacy while scaling to millions of users. Previous systems that hide metadata using Tor (such as Pond) are prone to traffic analysis attacks. Systems that encrypt metadata using techniques like DC-nets and PIR don't scale beyond thousands of users.

Vuvuzela uses efficient cryptography (NaCl) to hide as much metadata as possible and adds noise to metadata that can't be encrypted efficiently. This approach provides less privacy than encrypting all of the metadata, but it enables Vuvuzela to support millions of users. Nonetheless, Vuvuzela adds enough noise to thwart adversaries like the NSA and guarantees differential privacy for users' metadata.
Source : https://github.com/vuvuzela/vuvuzela

You have been warned : We kill people based on metadata