Partial

RFC 5883 - Bidirectional Forwarding Detection (BFD) for Multihop Paths

Every requirement this repository extracted from RFC 5883, the tests bound to it, and what a reader has verified about them. This summary is enrolled and gated by ./le rfc check.

Overview

Positive

what Ze has

Tested both ways75.0%6 of 8 binding obligations

a positive test proves Ze does what the requirement demands and a negative one proves it refuses what the requirement forbids

One polarity plus reason0.0%0 of 8 binding obligations

the requirement admits no counter-case, so one polarity plus a recorded reason is the whole proof available for it

One polarity, unexcused0.0%0 of 8 binding obligations

one direction is tested, the other is neither tested nor excused, and nothing states which

Proven by a recorded break0.0%0 of 12 tagged units

a red was observed once under a recorded procedure, and the unit, the claim and the producer it rested on still hash to what was recorded. The break is not re-run. A test pair is not a proof until one has been observed

Neutral

measures that are neither good news nor bad

Gated MUSTs8of 9 this summary declares

MUST-level requirements the gate HOLDS. A population, not a result: the shares beside it are what says how Ze stands

Out of scope0of 8 gated MUSTs

a {not-applicable} annotation says the obligation does not bind Ze. Scope, not coverage: it is in no share below

Negative

what Ze owes

No test at all25.0%2 of 8 binding obligations

no test carries the requirement id, whether or not a gap states why

The 4 shares marked as a part above are the whole of the 8 obligations that bind Ze: they add to 100%. Proven by a recorded break is a share of TAGGED UNITS, a different population, so it is not one of them.

How to read the colors

A color names what the measure MEANS, not how well Ze scores on it. Green is a good outcome at any value, red is a bad one, and neither a population nor a scope count is an outcome, so both take no color. The number under the label is what says how far Ze has got.

Card	Tone here	Why that color
Gated MUSTs	neutral	no color: a population is a scale, and a larger one is neither good news nor bad. It is the accounting total
Out of scope	neutral	no color: an obligation that never bound Ze is neither an achievement nor a failure, and counting it either way would be a claim
Tested both ways	ok	green at every value: a test pair is the outcome this gate exists to produce, and the share under the label is what says how far Ze has got
One polarity plus reason	ok	green at every value: where no counter-case exists, one polarity IS the complete answer, and a recorded reason is what the gate demands beside it
One polarity, unexcused	ok	green at zero, RED above it: half a proof with no reason for the other half
No test at all	bad	green at zero, RED above it: a binding obligation nothing exercises is a claim with nothing behind it, whether or not a reason is stated
Proven by a recorded break	ok	green at every value: an observed break is the outcome the discrimination gate exists to produce. The denominator is TAGGED UNITS, not obligations, so this share is not one of the parts above
Audit verdicts	warn	RED on the first weak, wrong or unimplemented verdict, amber while a verdict is no longer current or a gated MUST is unjudged, green when every one is judged sound and current

At a glance

Field	Value
Public status	Partial
Enrolment	Enrolled
Requirements	9
Gated MUST-level	8
Obligations that bind Ze	8
Not applicable, so out of scope	0
Declared gaps	2
Gated with no test	0
Nightly-only evidence	0
Test tags	12
Tagged units	12
Recorded audit verdicts	0
Discrimination records	0
Summary	`rfc/short/rfc5883.md`
Requirement shard	`rfc/requirements/rfc5883.md`
RFC text	`rfc/full/rfc5883.txt`

Enrolment

Enrolled: BFD for Multihop Paths: eight MUST-level requirements. Six are met with new positive+negative tests in internal/component/bfd asserting producer decisions: 5-1 (multihop uses UDP destination port 4784), 5-2 (single-hop 3784 and multihop 4784 use separate ports), 4.3-1 (a default session takes the Active role and arms its transmit timer), 4.3-2 (a Passive session stays silent until it receives a packet), and 3-1 / x-1 (BFD Echo is rejected on a multihop path). 7-1 and 7-2 (congestion detection and congestion-triggered transmit-rate reduction) are {gap}: ze has no BFD congestion-control code path (only slow-start and jitter). Disclosed in the docs/features/rfc-status.md RFC 5883 row.

What the public ledger says

Status: Partial

What the ledger says is covered:

Multi-hop UDP 4784 sessions, single-hop/multihop port separation (3784/4784), Active/Passive roles, echo-on-multihop rejection, and min-TTL floor
tests bound per requirement in rfc/requirements/rfc5883.md.

What the ledger says remains:

No BFD congestion control or congestion-triggered transmit-rate reduction (RFC 5883 / RFC 5880 Section 7); IPv6 dual-bind and wider deployment proof are tracked with BFD.

Coverage

Bucket	Count	What it counts
Positive and negative tests	6	one part of the gated population
Annotated instead of tested	2	one part of the gated population
One polarity only	0	one part of the gated population
No test and no annotation	0	one part of the gated population
Evidence that runs nightly only	0	an overlay: each of these is also counted by the part it falls in
Gated MUST-level requirements	8	every gated MUST falls in exactly one bucket above

Positive and negative tests (6): RFC5883-3-1, RFC5883-4.3-1, RFC5883-4.3-2, RFC5883-5-1, RFC5883-5-2, RFC5883-x-1

Annotated instead of tested (2): RFC5883-7-1, RFC5883-7-2

Requirements

Requirement	Level	Section	Tests
`RFC5883-3-1`	Echo function must not be used over multihop paths (§3)
	MUST NOT	3	positive`unit/verifyTestRFC5883SingleHopEchoAccepted` negative`unit/verifyTestRFC5883MultiHopEchoRejected`
`RFC5883-4.3-1`	Unidirectional Sender must operate in the Active role (§4.3)
	MUST	4.3	positive`unit/verifyTestRFC5883DefaultSessionActiveArmsTx` negative`unit/verifyTestRFC5883PassiveSessionDoesNotArmTx`
`RFC5883-4.3-2`	Unidirectional Receiver must operate in the Passive role (§4.3)
	MUST	4.3	positive`unit/verifyTestRFC5883PassiveSessionSilentUntilRx` negative`unit/verifyTestRFC5883PassiveSessionTransmitsAfterRx`
`RFC5883-5-1`	UDP destination port must be 4784 for multihop BFD Control packets (§5)
	MUST	5	positive`unit/verifyTestRFC5883MultiHopControlPort` negative`unit/verifyTestRFC5883MultiHopControlPortNotSingleHop`
`RFC5883-5-2`	Implementations must bind RX sockets to the correct port per session type (single-hop 3784 vs multihop 4784) (Pitfalls, §5)
	MUST	5	positive`unit/verifyTestRFC5883SingleHopControlPort` negative`unit/verifyTestRFC5883SeparatePortsPerMode`
`RFC5883-x-1`	Multihop implementations must reject attempts to enable Echo on a multihop session (Pitfalls)
	MUST	x	positive`unit/verifyTestRFC5883SingleHopEchoAccepted` negative`unit/verifyTestRFC5883MultiHopEchoRejected`
`RFC5883-7-1`	Congestion control must be implemented for multihop deployments (§7 of RFC 5880, referenced in Interop)
	MUST	7	positive`no test`no positive test negative`no test`no negative test {gap}: ze implements no BFD congestion detection or congestion-triggered transmit-rate reduction (internal/component/bfd/ has only slow-start and jitter); the RFC 5883 / RFC 5880 Section 7 congestion-control obligation is unmet
`RFC5883-7-2`	When congestion is detected, TX rate must be reduced (§7 of RFC 5880, referenced in Interop)
	MUST	7	positive`no test`no positive test negative`no test`no negative test {gap}: ze implements no BFD congestion detection or congestion-triggered transmit-rate reduction (internal/component/bfd/ has only slow-start and jitter); the RFC 5883 / RFC 5880 Section 7 congestion-control obligation is unmet
`RFC5883-6-1`	Cryptographic authentication should be used for all multihop sessions (§6)
	SHOULD	6	positive`no test`no positive test negative`no test`no negative test

Gaps and untested MUSTs

Requirement	State	Reason
`RFC5883-7-1` Congestion control must be implemented for multihop deployments (§7 of RFC 5880, referenced in Interop)	{gap}, no test	ze implements no BFD congestion detection or congestion-triggered transmit-rate reduction (internal/component/bfd/ has only slow-start and jitter); the RFC 5883 / RFC 5880 Section 7 congestion-control obligation is unmet
`RFC5883-7-2` When congestion is detected, TX rate must be reduced (§7 of RFC 5880, referenced in Interop)	{gap}, no test	ze implements no BFD congestion detection or congestion-triggered transmit-rate reduction (internal/component/bfd/ has only slow-start and jitter); the RFC 5883 / RFC 5880 Section 7 congestion-control obligation is unmet

Proof state

A tagged unit reads unproven where no discrimination record exists for it: nothing in this tree has been observed to break it, so the claim its tag makes is unproven.