Hello, I have been selected to do a routing directorate “early” review of this draft. https://datatracker.ietf.org/doc/draft-ietf-idr-bgp-model/ The routing directorate will, on request from the working group chair, perform an “early” review of a draft before it is submitted for publication to the IESG. The early review can be performed at any time during the draft’s lifetime as a working group document. The purpose of the early review depends on the stage that the document has reached. As this document is in working group last call, my focus for the review was to determine whether the document is ready to be published. Please consider my comments along with the other working group last call comments. For more information about the Routing Directorate, please see http://trac.tools.ietf.org/area/rtg/trac/wiki/RtgDir Document: draft-ietf-idr-bgp-model-07 Reviewer: Yingzhen Qu Review Date: 10 December 2019 Intended Status: Standards Track Summary Thank you for writing this document. It is a critical piece for IETF YANG support in general. This document is very well written. I think that it is almost ready to be published, but there are a few points below that I would like to discuss for clarification. I also spotted a few nits that should be fixed at some point before publication. Comments and Questions 1) about RIB This model defines BGP RIB, which augments RFC 8349. There are a few places it says just RIB instead of BGP RIB, and I’d suggest making it clear to be BGP RIB. For example: In Abstract: This document defines a YANG data model for configuring and managing BGP, including protocol, policy, and operational aspects, such as RIB, based on data center, carrier and content provider operational requirements. Section 1.1: o RIB contents. 2) About VRF support This question has been asked during WG session when the draft was presented. VRF support is through Network Instance model (RFC8529), however there is issue when trying to map a VRF to one of the several BGP instances. Example configuration is shown below: RP/0/RSP0/CPU0:ASR9001_RT21(config-bgp-vrf-af)#do show running-config  router bgp Tue Nov 19 10:02:04.130 UTC router bgp 100 instance a1 bgp router-id 12.12.12.12 address-family vpnv4 unicast ! neighbor 121.1.1.1   remote-as 100   address-family vpnv4 unicast   ! ! vrf vrf-a1 <— it needs some sort of binding information to relate this VRF to BGP instance a1. In this case, the key point is there are one than one BGP default instances.   rd auto   address-family ipv4 unicast    redistribute static   ! ! ! router bgp 200 instance a2 bgp router-id 13.1.1.1 address-family vpnv4 unicast ! address-family ipv6 unicast ! address-family l2vpn evpn ! neighbor 122.1.1.1   remote-as 100   address-family vpnv4 unicast   !   address-family l2vpn evpn   ! ! vrf a3   rd 13.1.1.1:2   address-family ipv4 unicast   ! ! vrf vrf-a2   rd 13.1.1.1:1   address-family ipv4 unicast    redistribute connected   ! ! ! router bgp 100 bgp router-id 1.1.11.1 address-family ipv4 unicast ! address-family vpnv4 unicast ! address-family l2vpn vpls-vpws ! Nits Overall the document is very well written and read well. Only a couple of nits: Section 3    The BGP model augments the Routing Management model A YANG Data Model    for Routing Management [RFC8349] which defines the notion of routing,    routing protocols, It seems that this long sentence could use a couple “,”.   Section 4:    These are the subtrees and data nodes    and their sensitivity/vulnerability: There are three paragraphs ending with this sentence, meant for writeable, read only and RPC operations data nodes, but the detailed nodes are missing.