I have reviewed this document as part of the Operational directorate's ongoing effort to review all IETF documents being processed by the IESG. These comments were written with the intent of improving the operational aspects of the IETF drafts. Comments that are not addressed in last call may be included in AD reviews during the IESG review. Document editors and WG chairs should treat these comments just like any other last call comments. This document extends IEEE 802.15.4 with 6TiSCH Join and Enrollment Information for layer 2 synchronization and layer 3 synchronization. I think this document is ready for publication. Major issue: Not found Minor issue: 1. Abstract Is small details about 6TiSCH join and enrollment information? If yes, why not document it explicitly? Also it will be great to clarify in the abstract why 6TiSCH join and enrollment information needs to be carried? For which purpose? 2 Section 1, 1st paragraph s/slot designated a broadcast slot/slot designated as a broadcast slot 3.Section 1.2 2nd paragraph s/annouce/announce 4. Section 1.2, last paragraph is slot/s slot per second? Please make clear about this. 5.Section 3, 2nd paragraph s/Beagon/Beacon 6.Section 4 Should the last paragraph be moved after the first sentence and before the second sentence in the first paragraph? How DODAGID is related to network ID? Should you add DODAGID as a new abbreviation or term? When Dogagid is hashed, how interloper can use the network ID to map out the extend of mesh network? What do you mean by the extend of the mesh network? s/ provides some cover the addresses used within the network/ provides some cover for the addresses used within the network.