%% You should probably cite rfc7252 instead of this I-D.
@techreport{ietf-core-coap-09,
    number =    {draft-ietf-core-coap-09},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-ietf-core-coap/09/},
    author =    {Zach Shelby and Klaus Hartke and Carsten Bormann and Brian Frank},
    title =     {{Constrained Application Protocol (CoAP)}},
    pagetotal = 91,
    year =      2012,
    month =     mar,
    day =       12,
    abstract =  {This document specifies the Constrained Application Protocol (CoAP), a specialized web transfer protocol for use with constrained networks and nodes for machine-to-machine applications such as smart energy and building automation. These constrained nodes often have 8-bit microcontrollers with small amounts of ROM and RAM, while networks such as 6LoWPAN often have high packet error rates and a typical throughput of 10s of kbit/s. CoAP provides a method/response interaction model between application end-points, supports built-in resource discovery, and includes key web concepts such as URIs and content-types. CoAP easily translates to HTTP for integration with the web while meeting specialized requirements such as multicast support, very low overhead and simplicity for constrained environments.},
}