# OPSDIR Early Review of draft-ietf-bess-evpn-mvpn-seamless-interop-09 

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.

The document is well-written. The motivation is clear.

The document does not include a dedicated Operational Considerations section. Please consider adding one —draft-opsarea-rfc5706bis provides some useful information.


## Minor
Section 8.2 and Section 9. 
As the current text primarily focuses on MPLS and VXLAN, I propose the inclusion of SRv6 (Segment Routing over IPv6) encapsulation to enhance the future applicability and completeness of the solution
Section 8.2
Suggestion: Please introduce a dedicated subsection to cover SRv6 encapsulation.
Section 9
Suggestion: Following the discussion of the MPLS/VXLAN inter-connect, please add a discussion of the SRv6/VXLAN scenario.

## Nits
1.Please ensure the term "VxLAN" is consistently capitalized as VXLAN throughout the document to comply with the spelling used in RFC 7348.
2.Please perform a global check to remove unnecessary white spaces that appear throughout the document.
-s/( Since EVPN PE/( Since EVPN PE (Remove extra spaces before 'Since')
-s/( PE's loopback address/( PE's loopback address (Remove extra spaces before 'PE's')
-s/( Refer Section 13)/ (Refer Section 13) (Remove extra spaces before 'Refer')
3.Terminology Section：
Please add the full definition for IRB to the Terminology section, referencing RFC9135.
IRB: Integrated Routing and Bridging interface. It connects an IP-VRF to a BD (or subnet).
-s/NVE: Network Virtualization Endpoint/NVE: Network Virtualization Edge（Consistent with RFC8365 and RFC9135）
-s/PE: Provider Edge device/ PE: Provider Edge
-s/VNI: Virtual Network Identifier (for VXLAN)/ VNI: VXLAN Network Identifier（Consistent with RFC8365）
-s/VXLAN: Virtual Extensible LAN/ VXLAN: Virtual eXtensible LAN（Consistent with RFC7348）
4. 
-s/I.e,/i.e.,
-s/External source and receivers/External Source and Receivers
-s/IRB multicast in seamless interop mode/IRB Multicast in Seamless Interoperability Mode
-s/ Setup of overlay multicast delivery/ Setup of Overlay Multicast delivery
-s/Handling of different encapsulations/ Handling of Different Encapsulations
-s/Data plane interconnect/Data Plane Interconnect
-s/Control plane inter-connect/Control Plane Interconnect
-s/Connecting external Multicast networks/Connecting External Multicast Networks
-s/multihoming of IP multicast sources and receivers/ Multihoming of IP multicast sources and receivers
-s/an temporary/a temporary
-s/specificied/specified
5. Section 6.1
OLD：
   As described in Section 5.4.2, when a multicast source is sitting
   behind an All-Active ES, then an intra-subnet multicast tunnel is
   needed among the multihoming EVPN PEs for that ES to carry multicast
   flow received by one of the multihoming PEs to the other PEs in that
   ES.  We refer to this multicast tunnel as an Intra-ES subnet tunnel.
NEW：
   As described in Section 5.4.2, when a multicast source is sitting
   behind an All-Active ES, then an intra-subnet multicast tunnel is
   needed among the multihoming EVPN PEs for that ES to carry multicast
   flow received by one of the multihoming PEs to the other PEs in that
   ES.  This multicast tunnel is referred to as an Intra-ES subnet tunnel.
Section 9:
   This section describes the inter-operation between MVPN PEs in WAN
   using MPLS encapsulation with EVPN PEs in a DC network using VxLAN
   encapsulation.  Since the tunnel encapsulation between these networks
   are different, we must have at least one gateway in between.
NEW:
   This section describes the inter-operation between MVPN PEs in WAN
   using MPLS encapsulation with EVPN PEs in a DC network using VXLAN
   encapsulation. Since the tunnel encapsulation between these networks
   are different, it must have at least one gateway in between

6. Please review the references sections. If all referenced documents are normative, please delete Section 16.2 " Informative References " as it is redundant.

Thanks!
Ran