Last Call Review of draft-ietf-idr-tunnel-encaps-19
review-ietf-idr-tunnel-encaps-19-genart-lc-mishra-2020-10-02-2-00

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Document: draft-ietf-idr-tunnel-encaps-??
Reviewer: Gyan Mishra
Review Date: 2020-10-02
IETF LC End Date: 2020-10-01
IESG Telechat date: Not scheduled for a telechat

Summary:
   This draft updates RFC 5512 is which was never used in production.
    This document deprecates the original RFC 5512
   Encapsulation SAFI used for GRE encapsulation type only and defined extended
   community attributes  (which has never been used in production) , and
   specifies semantics for the attribute when it is carried in UPDATEs of
   certain other SAFIs.  This document adds support for additional Tunnel
   Types, and allows a remote tunnel endpoint address to be specified for each
   tunnel.  This document also provides support for specifying fields of any
   inner or outer encapsulations that may be used by a particular tunnel.

This document is well written and clearly defines all the tunnel encapsulation
attributes that exist today. This draft modification of the usage of the tunnel
encapsulation attribute is backwards compatible so does not impact the existing
deployments of the tunnel encapsulation types such as vxlan,vxlan GPE, NVGRE,
MPLS over GRE, L2TPV3.

Major issues:
None

Minor issues:
Is tunnel type RFC 7510 MPLS over UDP supported.  Also RFC 8663 SR-MPLS over IP
for SRv6 and SR-MPLS interoperability where MPLS over GRE RFC 4023 is used or
RFC 7510 MPLS over UDP and outer encapsulation is IPv6 for SRv6 forwarding
plane to tunnel SR-MPLS.

Nits/editorial comments:
As this update is backwards compatible to tunnel encapsulation attributes
deployed today is there any code upgrade for vendor implementation required now
for router vendors to support the new encapsulation attributes TLV and Sub TLVs
and extended community attributes defined with this draft.