Shepherd writeup

## Shepherd Writeup


* Document Shepherd: Jaime Jiménez, <>
* Area Director: Mirja Kuehlewind <>

The CoAP protocol needs to be implemented in such a way that it does
not cause persistent congestion on the network it uses.  The CoRE
CoAP specification defines basic behavior that exhibits low risk of
congestion with minimal implementation requirements.  It also leaves
room for combining the base specification with advanced congestion
control mechanisms with higher performance.

This specification defines more advanced, but still simple CoRE
Congestion Control mechanisms, called CoCoA.  The core of these
mechanisms is a Retransmission TimeOut (RTO) algorithm that makes use
of Round-Trip Time (RTT) estimates, in contrast with how the RTO is
determined as per the base CoAP specification (RFC 7252).  The
mechanisms defined in this document have relatively low complexity,
yet they improve the default CoAP RTO algorithm.  The design of the
mechanisms in this specification has made use of input from
simulations and experiments in real networks.

The document is intended as Informational, as it provides an optimisation of the existing CoAP congestion control mechanism with a Retransmission TimeOut (RTO) algorithm based on RTT estimation. 

###Review and Consensus

The document has gone through multiple expert reviews and has been discussed on multiple IETF meetings. Before the last IETF the WGLC was completed.

###Intellectual Property

Each author has stated that they do not have direct, personal knowledge of any IPR related to this document. I am not aware of any IPR discussion about this document on the CoRE WG.

###Other Points
There are RFC Editor comments that need to be edited out.
This document makes no requirements on IANA.


* [x] Does the shepherd stand behind the document and think the document is ready for publication?
* [x] Is the correct RFC type indicated in the title page header?
* [x] Is the abstract both brief and sufficient, and does it stand alone as a brief summary?
* [x] Is the intent of the document accurately and adequately explained in the introduction?
* [x] Have all required formal reviews (MIB Doctor, Media Type, URI, etc.) been requested and/or completed?
* [x] Has the shepherd performed automated checks -- idnits (see and the Internet-Drafts Checklist), checks of BNF rules, XML code and schemas, MIB definitions, and so on -- and determined that the document passes the tests?
* [x] Has each author stated that their direct, personal knowledge of any IPR related to this document has already been disclosed, in conformance with BCPs 78 and 79?
* [x] Have all references within this document been identified as either normative or informative, and does the shepherd agree with how they have been classified?
* [x] Are all normative references made to documents that are ready for advancement and are otherwise in a clear state?
* [x] If publication of this document changes the status of any existing RFCs, are those RFCs listed on the title page header, and are the changes listed in the abstract and discussed (explained, not just mentioned) in the introduction? `Does not apply`
* [x] If this is a "bis" document, have all of the errata been considered? `Does not apply`

* **IANA** Considerations: `There are no requirements on IANA`

	* [x] Are the IANA Considerations clear and complete? Remember that IANA have to understand unambiguously what's being requested, so they can perform the required actions.
	* [x] Are all protocol extensions that the document makes associated with the appropriate reservations in IANA registries?
	* [x] Are all IANA registries referred to by their exact names (check them in to be sure)?
	* [x] Have you checked that any registrations made by this document correctly follow the policies and procedures for the appropriate registries?
	* [x] For registrations that require expert review (policies of Expert Review or Specification Required), have you or the working group had any early review done, to make sure the requests are ready for last call?
	* [x] For any new registries that this document creates, has the working group actively chosen the allocation procedures and policies and discussed the alternatives?
	* [x] Have reasonable registry names been chosen (that will not be confused with those of other registries), and have the initial contents and valid value ranges been clearly specified?