The IESG has approved the following document: - 'Observing Resources in CoAP' (draft-ietf-core-observe-16.txt) as Proposed Standard This document is the product of the Constrained RESTful Environments Working Group. The IESG contact persons are Ben Campbell, Barry Leiba and Alissa Cooper. A URL of this Internet Draft is: https://datatracker.ietf.org/doc/draft-ietf-core-observe/ Technical Summary This specification extends the CoAP protocol (RFC 7252) to allow for CoAP clients to "observe" changing server-side resources, using a model of eventual consistency (not every intermediate state is necessarily delivered). It is intended for standards-track as it is a widely implemented extension of a standards-track protocol. Review and Consensus The specification was developed along with the base CoAP specification and received significant review by active WG members and implementers. One remaining smaller issue without an obvious answer, how to actively cancel an ongoing observation from the client side, remained under discussion for quite some time before a solution was finally picked at IETF89 in London. Several implementations of this final (post-London) version have completed an interoperability test event with a very good score. Further implementer feedback also was positive. Parts of the specification have already been picked up earlier in OMA LWM2M and are an element of their 1.0 specification. The specification benefited from the directorate reviews of the base specification (in particular with respect to congestion control), but no separate directorate review of this extension has been performed. Personnel Carsten Bormann is the document shepherd. Barry Leiba is the responsible Area Director. RFC Editor note Please make the following change at the end of Section 3.5: OLD observers. NEW observers (Section 4.5).
