cacaoweb uses a number of technology revolving around p2p. Some technologies used in cacaoweb:
From Wikipedia: A distributed hash table (DHT) is a class of a decentralized distributed system that provides a lookup service similar to a hash table; (key, value) pairs are stored in a DHT, and any participating node can efficiently retrieve the value associated with a given key. Responsibility for maintaining the mapping from keys to values is distributed among the nodes, in such a way that a change in the set of participants causes a minimal amount of disruption. This allows a DHT to scale to extremely large numbers of nodes and to handle continual node arrivals, departures, and failures.
Distributed relational database
The feature, that builds on cacaoweb distributed hashtable, allows to store and access full relational databases and query them via an SQL-like language.
cacaoweb has a lot of p2p communications primitives, this allows two peers to initiate a direct communication to each other in UDP or TCP in any situation.
One of the most strikingly popular feature is p2p streaming. With the use of smart communication algorithms, cacaoweb provides realtime multimedia consumption to users.