Reviewer: Yoshiro Yoneya
Review result: Ready with Nits

  I am assigned ARTART reviewer for this draft.

Summary:

  This draft is in good shape and almost ready for publication.  I found a few nits better to be considered.

Major issues:

  None.

Minor issues:

  None.

Nits:

  ==
  In Section "4. Configuration":

  CURRENT
  1.  Issuer Request URL: A token request URL for generating access
       tokens.  For example, an Issuer URL might be
       https://issuer.example.net/request.

  SUGGESTION
  1.  Issuer Request URI: A token request URI for generating access
       tokens.  For example, an Issuer URI might be
       https://issuer.example.net/request.

  This is because URI is normative term for URL in IETF.
  I found the term "URL" in this document at several places and they could be replaced by "URI" as well.

  ==
  In Section "5.1. Client-to-Issuer Request":

  CURRENT
  *  "token_type" is a 2-octet integer, which matches the type in the
      challenge.

  SUGGESTION
  *  "token_type" is a 2-byte integer, which matches the type in the
      challenge.

  There seems no reason to use the term "octet" in this document. By definition of the data structure, byte == 8bit (uint8_t) is obvious.
  I found the term "octet" in this document at several places and they could be replaced by "byte" as well.