I've reviewed this draft for the security directorate. This draft specifies the PCN protocol for the mode in which only a single mark is present. This protocol operates among a set of nodes trusted to enforce PCN behavior and to properly police traffic entering and leaving the network. This document referrs to a previous RFC for security considerations. The considerations documentedseem adequate, and for that reason I have no comments on this document. Had I been assigned the previous RFC, I might have had more comments, but we've already reached consensus on that document and published it, so let's move forward.