Technical Summary
This version of the draft updates the 'ietf-bfd-types' module to
define a new feature called 'client-base-cfg-parms and a 'if-feature'
statement that conditionally includes definition of parameters such
as 'multiplier' or 'desired-min-tx-interval'. The feature statement
allows YANG implementations of protocol such as OSPF, ISIS, PIM and
BGP, to support both a model where such parameters are not needed,
such as when multiple BFD sessions are supported over a given
interface, as well as when they need to be defined per session. As a
result, the BFD MPLS module has to use the base-cfg-parms instead of
client-cfg-parms to be able to include all the parameters
unconditionally.
Working Group Summary
While the desired YANG changes were very small, this update is occurring a
short time after the original publication of RFC 9127. It was decided to, as
much as possible, to simply re-issue RFC 9127 to avoid potential confusion
about the authoritative contents of the YANG modules for BFD.
Consultation with the YANG doctors did indicate that a smaller document
containing only the minimum required updates was an option. However, the
authors and the interested parties in the Working Group participating in the
discussion pushed for the larger document.
The primary consideration that kept this document from being a simple copy and
paste of the original RFC 9127 with the minor necessary changes was the
iana-bfd-types module which was previously delegated to IANA in RFC 9127, and
thus not eligible for re-publication in this document.
Document Quality
This module is intended to be leveraged both as the BFD management module along
with providing BFD configuration for other IETF modules. It was as part of
assessing impacts on other routing protocols that the motivating work for this
update was discovered.
The YANG doctors were consulted as part of this work, but no formal review was
requested. Since this is largely a republication of RFC 9127, it is presumed
that prior work this is based upon is well reviewed.
Personnel
: Who is the Document Shepherd?
Jeffrey Haas.
: Who is the Responsible Area Director?
John Scudder.