After a successful 6LowApp BOF at Hiroshima, an Internet Draft on the feature analysis of the Constrained Application Protocol (CoAP) has been posted!. The document analyzes the requirements for CoAP from the proposed 6LowApp charter, identifies the key features and possible ways of realizing each feature, and covers the applicability of these features to energy, building automation and general M2M applications.
"This document considers the requirements and resulting features needed for the design of the Constrained Application Protocol (CoAP). Starting from requirements for energy and building automation applications, the basic features are identified along with an analysis of possible realizations. The goal of the document is to provide a basis for protocol design and related discussion.
The use of web services on the Internet has become ubiquitous in most applications, and depends on the basic REST architecture of the web. The proposed Constrained RESTful Environments (CoRE) working group aims at extending the REST architecture to a suitable form for the most constrained nodes (e.g. 8-bit microcontrollers with limited RAM and ROM) and networks (e.g. 6LoWPAN). One of the main goals of CoRE is to design a generic RESTful protocol for the special requirements of this constrained environment, especially considering energy and building automation applications. The result of this work should be a Constrained Application Protocol (CoAP) which easily traslates to HTTP for integration with the web while meeting specialized requirements such as multicast support, very low overhead and simplicity."