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Document: draft-ietf-dmarc-arc-protocol-18
Reviewer: Ines Robles	
Review Date: 11-03-2018
IETF LC End Date: 11-06-2018
IESG Telechat date: (if known)

Summary:

I believe the draft is technically good. This document is well written and clear to understand.

This document describes the Authenticated Received Chain (ARC) protocol, which provides an authenticated "chain of custody" for a message, allowing each entity that handles the message to see what entities handled it before, and to see what the message's authentication assessment was at each step in the handling.

I like that the document mentions the available implementations.

Major issues: Not found

Minor issues:

There is a TODO in Appendix B, so I suppose further information will be added to the draft later.

Nits/editorial comments: 

Page 18: “ptypes” →types
Page 22: “concocted” → connected? 

Thank you for this draft.

Ines