A Light weight private messaging (and chat) fabric/protocol, with direct, relayed, and P2P modes, mainly for Internet of Things (IoT).
chatFabric is an open source, binary, Layer 7 protocol allowing secure communication and control of Internet of Things or embedded devices. Being originally developed small embedded devices and mobile apps, it could easily be also used for monitoring cloud based computing systems as well. With all packets under 1400 bytes, it has really low overhead.
Find chatFabric over on github.