Update July 23rd 2020. Comments on draft-ietf-bfd-stability-06
General: NULL authentication TLV is still used, should be replaced with NULL
authentication type or section as appropriate. Be consistent for Null v/s NULL
(NULL Auth is used in bfd-optimizing-authentication)
Introduction
s/detect lost packet/detect lost packets/
Section 3 Use Cases:
s/any BFD packet loss if loss/any BFD packet loss if the loss/
s/BFD implementation/BFD implementations/
Where the text says “failure of a link”, might be better to say “failure of a
datapath”? Informative references to CFM and TWAMP would be useful
Section 4
“by appending the Null-Authentication type “. Suggest “by appending an
authentication section with the NULL Authentication type “
Section 5
“BFD uses authentication TLV”, suggest change to “BFD uses an authentication
section”.
“BFD packets MUST include NULL-Auth TLV”. Change to “BFD control packets MUST
include an authentication section with the NULL Authentication type”
Section 5.1
“The first BFD NULL-Auth type processed by the receiver…”. Change to “The
first BFD authentication section with the NULL Authentication type, in a valid
BFD control packet, processed by the receiver” . Also, does it have to be NULL
Auth, I believe it can be any auth with sequence number? If that’s the case
change to “The first BFD authentication section with a non-zero sequence
number, in a valid BFD control packet, processed by the receiver is used for….”.
===================
(1) What type of RFC is being requested (BCP, Proposed Standard, Internet
Standard, Informational, Experimental, or Historic)? Why is this the proper
type of RFC? Is this type of RFC indicated in the title page header? Standards
Track as indicated on title page.
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Please provide such a Document Announcement Write-Up. Recent examples can be
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announcement contains the following sections:
Technical Summary:
This document describes extensions to the Bidirectional Forwarding
Detection (BFD) protocol to measure BFD stability. Specifically, it
describes a mechanism for detection of BFD control packet loss.
Relevant content can frequently be found in the abstract and/or introduction of
the document. If not, this may be an indication that there are deficiencies in
the abstract or introduction.
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There have been many discussions since 2014 on this document. The document has
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removed.
Was there anything in WG process that is worth noting? For example, was there
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The document is well-written, concise and technically accurate, but requires
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Reshad Rahman, BFD co-chair.
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summarize any WG discussion and conclusion regarding the IPR disclosures. No
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Boilerplate checks are not enough; this check needs to be thorough. 1 comment
regarding document date being 106 days in the past.
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RFC8342? N/A
COMMENTS
General:
- Don’t use NULL-authentication TLV, use RFC5880 language.
e.g.NULL-authentication type. - s/control frame/control packet/ (reuse
same terms as in RFC5880) - CC frames is not defined in BFD, use “control
packets” instead? - Terminology section would help. In there: secure
sequence numbers, meticulous authentication etc could be added. - Missing
“the”, “an” in a few sentences.
Introduction
Following sentence is long and not super clear, what’s the essence of the point
it’s trying to make? I’m having a hard time digesting “…, the tolerance for
lost or delayed frames in the Detection Time,”. Is it just saying that
Detection Time is usually set to smallest value and because of this there’s
little tolerance for delayed/lost packets? Needs tweaking.
.In order to
prevent significant data loss due to a datapath failure, the
tolerance for lost or delayed frames in the Detection Time, as
defined in BFD [RFC5880] is set to the smallest feasible value.
s/does not propose BFD extension/does not propose any BFD extension/
Requirements Language
Please put this is a separate (sub)section later in the doc, e.g. after intro.
Add RFC8174, and have RFCs 2119 and 8174 as normative references.
2. Use cases
Legacy BFD? Why not say BFD as specified in RFC5880. Or add “Legacy BFD” in
terminology section.
Instead of “dead interval”, use “Detection Time” as defined in RFC5880.
s/This draft/This document/
s/enables BFD engine/enables the BFD engine/
Instead of “BFD engine”, use “BFD implementation”? I understand what you mean
by “BFD engine”, and ok if you keep it, but it’s not a term I’ve seen in BFD
drafts/RFCs.
s/In a faulty datapath scenario, operator/In a faulty datapath scenario, an
operator/ Add references for CFM and TWAMP in last paragraph?
3. BFD Null-Authentication TLV
Rename to BFD Null-Authentication section?
s/BFD control frame that do not/BFD control packets that do not/
Suggestion: consider putting this is a sub-section of section 4 “Theory of
operation”?
4. Theory of operations
s/4. Theory of operations/4. Theory of operation/
s/This mechanism allows operator/This mechanism allows operators/
4.1
Following needs clarification. What is “appropriately recorded”? For secure
sequence number, add normative reference to
draft-ietf-bfd-secure-sequence-numbers.
When using
secure sequence numbers, if the expected values are pre-calculated,
the matched value must be appropriately recorded to detect lost
frames.