CoAP – Constrained Application Protocol

I have been used this protocol for with my 6LowPan. it adds reliability to UDP without a lot of the overhead of TCP, this becomes incredibly important in constrained devices. In addition, the fact that google appears to be using it in THREAD could give its utilization a boost.

One thing I particularly like about CoAP is the /.well-known URI support (http://tools.ietf.org/html/rfc7252#section-7). It lets you implement services with easily discoverable data endpoints. E.g. IoT sensor devices can be made self-documenting in a lightweight manner.