Hello,

I've been selected as Routing Directorate (early) reviewer for this draft. 

I have a few nits (nothing major) and a couple of suggestions.

Some of my comments might come through as pedantic -- mostly due to my superficial prior knowledge concerning VRRP!


# Abstract:

suggested change/clarification
"...sub-second convergence of the Active router and..."
=> "...sub-second convergence for the process determining the Active router and..."
or something equivalent.


# Section 1:

suggested change/clarification
"this document demonstrates how... can enable faster detection..."
=> "this document specifies fast transition to a new Active router, upon detection of..."
or something equivalent.


# Section 2:

"Supporting sub-second mode... in the data plane may prove challenging"
=> Would be best to hint at the main reason why (costs in terms of control traffic overhead?).

"BFD already has many implementationq based on HW"
=> Cite at least one implementation, if possible?


# Section 3:

My Discriminator => cite RFC5880 upon first use of this term in the doc ;)

"... starts transmitting BFD control packets with VRID as a source IP address and ..."
=> it is unclear how VRID (1 Byte) can be used as IP address. Can you rephrase/clarify?

"... when a backup router detects failure of the Active router, ..."
=> using which mechanism/RFC ? I suggest citing it explicitly

"... it reevaluates its role as VRID."
=> it is unclear how this happens exactly. If this is intentionally left unspecified as implementation-dependent, I suggest to say it explicitly in the doc.

"... the new Active router MUST select My Discriminator and..."
=> it is unclear which discriminator is meant here. Do you mean the value locally allocated (as it was still Backup router)?


# Section 5:

"... to accelerate detecting a failure that affects VRRP"
=> it is unclear what in the doc accelerates *detecting* a failure. I suggest a rephrase such as "...to accelerate transition to a new Active router upon detection of BFD failure" or something equivalent.