%% You should probably cite rfc9175 instead of this I-D.
@techreport{ietf-core-echo-request-tag-01,
    number =    {draft-ietf-core-echo-request-tag-01},
    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-echo-request-tag/01/},
    author =    {Christian Amsüss and John Preuß Mattsson and Göran Selander},
    title =     {{Echo and Request-Tag}},
    pagetotal = 19,
    year =      ,
    month =     ,
    day =       ,
    abstract =  {This document specifies several security enhancements to the Constrained Application Protocol (CoAP). Two optional extensions are defined: the Echo option and the Request-Tag option. Each of these options provide additional features to CoAP and protects against certain attacks. The document also updates the processing requirements on the Block options and the Token. The updated Token processing ensures secure binding of responses to requests.},
}