[$] Rollercoaster: group messaging for mix networks

Even encrypted data sent on the internet leaves some footprints-metadataabout where packets originate, where they are bound, and when they are sent. Mix networks aremeant to hide that metadata by routing packets through various intermediatenodes to try to thwart the traffic analysis used by nation-state-leveladversaries to identify "opponents" of various kinds. Tor is perhaps thebest-known mix network, but there are others that make differenttradeoffs to increase the security of their users. Rollercoasteris a recently announced mechanism that extends the functionality of mixnetworks in order to more efficiently communicate among groups.