radioAe6rt

JXTA provides a high level application API for sending data to peers in a peergroup. JXTA “propagate pipes” resemble IP multicast in their functionality: write data to a propagate pipe and any peer bound to the pipe receives the data. Peers discover routes to each other as a result of underlying JXTA platform services. This route discovery allows the packets written to the abstract pipe mechanism to find, similar to multicast, their way to other peers listening on that pipe.

Currently pipes are implemented over TCP, but work is in progress that may admit UDP transport. Such a lightweight transport would be an important next step in allowing audio over JXTA to succeed, over propagate pipes or other varieties of JXTA pipes.

Realtime audio over JXTA would be a powerful open source point of departure on the way to a Skype alternative.

Update 20 Dec 2005: I’ve prototyped a version of AE6RT Beacon that writes 16ms of audio 60/s to a propagate pipe. A peer reading the messages on the same pipe renders to what is quite intelligible audio. Traffic is going purely peer to peer over TCP, and over IPv6 at that on my home network.