Spartic provides a way for small groups of people to create virtual spaces where nobody either in or outside the group can know who is who.
Any message exchanged in such a space could have come from any participant; only the content of the message can provide any clue to the sender's identity.
Unlike systems such as Tor, which achieve anonymity by forwarding traffic, in Spartic all participants carry only their own messages.
Spartic achieves its anonymity through synchronized keystreams: the participants in a group are able to create random strings of bits that, while unpredictable, are guaranteed to XOR to zero when all combined. Each participant publishes their stream to all other participants, with their messages XORed in. By XORing the streams they received with the one they sent, each participant can recover a stream containing all the (nonoverlapping) messages, but no participant can identify any other participant as having sent any particular message.
If the parties coordinate perfectly on which pseudonym within the system is allowed to write to any given bit, then for N parties sending B bits of content from one party to another, an additonal (N - 1) * B bits of overheadare required. (More overhead may be required for re-keying faster than information leaks form the synchronized keystreams' secrets.)
To avoid parties being identified because they sent packets first, it is recommended to schedule the transmission of bits at a predefined rate, and for changes to that rate to be negotiated within the virtual space.