This draft has limited security relevance.  The parties involved are largely mutually trusting, and this draft doesn't significantly affect their relationships.

Use of a 40-bit unsigned integer deserves special care in implementation.

Abstract:

> The document updates RFC 8584 and related EVPN DF
>   election extensions (i.e. draft-ietf-bess-evpn-per-mcast-flow-df-
>   election and draft-ietf-bess-evpn-pref-df)

You can't update an unpublished draft.  Presumably the intent is to describe some way in which this concept interacts with the content of those drafts, but it isn't an "update".

Section 4.1:

> Value-
>   Units code points other than those defined in this document are out
>   of scope.

This is unclear, and the matter is clarified in Section 4.1.1.  It would be clearer to drop this sentence or write "No other Value-Units code points are defined at this time.".