Partial

RFC 5905 - Network Time Protocol Version 4: Protocol and Algorithms Specification

Every requirement this repository extracted from RFC 5905, 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 ways0.0%0 of 8 gated MUSTs

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 gated MUSTs

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 gated MUSTs

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

Partial proof; remaining gap0.0%0 of 8 gated MUSTs

scoped tests exist; the remaining obligation is unmet or unproven, with zero whole-requirement credit

Proven by a recorded break0.0%0 of 0 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 8 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

an obligation that does not bind Ze. A {not-applicable} annotation says it never bound; a {feature-declined} annotation says its condition is an optional feature Ze does not offer, and quotes the RFC sentence that makes it optional. Scope, not coverage: it stays in the denominator every share on this page is taken over

Not applicable0.0%0 of 8 gated MUSTs

a {not-applicable} annotation says the obligation does not bind Ze, so no test is owed for it. It stays in the denominator every share here is taken over

Met below Ze0.0%0 of 8 gated MUSTs

a {lower-layer} annotation says a layer under Ze performs the behavior, on state Ze installs into that layer, and names the producer that installs it. The obligation binds Ze and is met; Ze proves none of it, because its own boundary carries no value the behavior reads

Optional feature declined0.0%0 of 8 gated MUSTs

a {feature-declined} annotation says the obligation is conditional on a feature the RFC makes optional and Ze does not offer, and it quotes the sentence that makes it optional. The condition is false, so nothing is owed and nothing is missing. It stays in the denominator every share here is taken over

Linux cannot do this0.0%0 of 8 gated MUSTs

Linux cannot provide the primitive this requirement needs. The obligation still binds Ze and remains unmet; it stays in every denominator and earns no proof credit

Negative

what Ze owes

No test at all100.0%8 of 8 gated MUSTs

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

The 9 shares marked as a part above are the whole of the 8 gated MUSTs: 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
Partial proof; remaining gap	ok	green at zero, RED above it: a tested clause cannot prove the whole requirement
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
Not applicable	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
Met below Ze	neutral	no color: an obligation met below Ze is neither a test Ze wrote nor work Ze owes, and the two green shares above are what says how much Ze proves itself
Optional feature declined	neutral	no color: an obligation whose condition Ze never meets is neither an achievement nor a failure. The absent FEATURE is disclosed on the RFC's own status row, as an implementation gap a later scope decision can revisit
Linux cannot do this	neutral	neutral at every value: an evidenced platform limit is neither a proof nor a scope exemption
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	8
Gated MUST-level	8
Not applicable, so out of scope	0
Declared gaps	8
Declared gaps a test demonstrates	0
Gated with no test	0
Nightly-only evidence	0
Test tags	0
Tagged units	0
Recorded audit verdicts	0
Discrimination records	0
Summary	`rfc/short/rfc5905.md`
Requirement shard	`rfc/requirements/rfc5905.md`
RFC text	`rfc/full/rfc5905.txt`

Enrolment

Enrolled: NTPv4 protocol and algorithms. Ze is an SNTP-style client (Section 14): it queries its configured and DHCP-learned servers, picks one sample and steps or slews the clock, without the Section 9 and later mitigation algorithms. Every MUST-level row is classified: the full-suite, alternative-algorithm and association-reset rows (RFC5905-2-1, RFC5905-2-2, RFC5905-11.2.3-1) and the kiss-of-death handling rows are gaps owned by plan/post-release/features/spec-ntp-client-kiss-of-death.md. No owner ruling names the full NTPv4 suite unwanted (ai/META-DECISIONS.md, Goal and scope), so the Section 14 subset Ze ships is recorded as a gap, not a declined feature.

What the public ledger says

Status: Partial

What the ledger says is covered

SNTP client of RFC 5905 Section 14: per-server query, reach register, absurd-timestamp and Validate rejection (stratum 0 kiss-of-death, unsynchronized leap, invalid stratum), one selected sample, step or slew of the system clock
servers from configuration and from DHCP.

What the ledger says remains

No NTP server or peer mode, no Section 9 and later mitigation (clock filter, selection, cluster, combine, discipline), so the client is not the entire suite (RFC5905-2-1) and its one-sample choice is not output-identical to it (RFC5905-2-2); a clock step does not reset the associations (RFC5905-11.2.3-1). Kiss-of-death codes are rejected as samples but never inspected: DENY and RSTR do not demobilize the server and RATE does not slow polling (RFC5905-7.4-1, RFC5905-7.4-2, RFC5905-7.4-3, RFC5905-7.4-4); a KoD packet's transmit timestamp is read by the absurd-year check before the packet is discarded (RFC5905-7.4-5).

Coverage

Bucket	Count	What it counts
Positive and negative tests	0	one part of the gated population
Annotated (including scoped evidence)	8	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
Partial proof; remaining gap (subset of annotated; zero whole-requirement credit)	0	an overlay: each of these is also counted by the part it falls in
Evidence that runs nightly only	0	an overlay: each of these is also counted by the part it falls in
Derived from other rows	0	outside the gated population: each asserts nothing and derives its state from the rows it names, which the parts above already count
Gated MUST-level requirements	8	every gated MUST falls in exactly one bucket above

Annotated (including scoped evidence) (8): RFC5905-2-1, RFC5905-2-2, RFC5905-7.4-1, RFC5905-7.4-2, RFC5905-7.4-3, RFC5905-7.4-4, RFC5905-7.4-5, RFC5905-11.2.3-1

Attainable ceiling

Mandatory ceiling: 8 of 8 (100.0%). Optional ceiling: no rows. Every RFC shown with measured rows can reach 100% under current classifications. Lowest mandatory ceiling: rfc5905 8 of 8 (100.0%). Ceilings describe current classifications, not an immutable Linux maximum. Not-applicable and feature-declined classifications can be revisited. Every gap remains work Ze owes.

Requirements

Requirement	Level	Section	Tests
`RFC5905-2-1`	All servers and clients who are fully NTPv4-compliant MUST implement the entire suite of algorithms described in this document. (§2)
	MUST	2	positive`no test`no positive test negative`no test`no negative test {gap}: Ze implements the Section 14 SNTP subset, not the entire suite: internal/plugins/ntp/ntp.go::doSync queries each server once per round and keeps its latest sample, with no clock filter, selection, cluster, combine or clock discipline algorithm; no owner ruling names this feature unwanted (ai/META-DECISIONS.md, Goal and scope)
`RFC5905-2-2`	Alternative algorithms MAY be used, but their output MUST be identical to the algorithms described in this specification. (§2)
	MUST	2	positive`no test`no positive test negative`no test`no negative test {gap}: internal/plugins/ntp/ntp.go::doSync picks one server with internal/plugins/ntp/state.go::selectBestServer over each server's latest sample, an alternative to the Section 10 and 11 algorithms whose output is not identical to theirs; no owner ruling names this feature unwanted (ai/META-DECISIONS.md, Goal and scope)
`RFC5905-7.4-1`	Recipients of kiss codes MUST inspect them and, in the following cases, take these actions: (§7.4)
	MUST	7.4	positive`no test`no positive test negative`no test`no negative test {gap}: doSync in internal/plugins/ntp/ntp.go discards a stratum-0 response through resp.Validate and logs the error; the kiss code is never read
`RFC5905-7.4-2`	For kiss codes DENY and RSTR, the client MUST demobilize any associations to that server and stop sending packets to that server; (§7.4)
	MUST	7.4	positive`no test`no positive test negative`no test`no negative test {gap}: a server answering DENY or RSTR stays in the server list and is queried again every round; internal/plugins/ntp/ntp.go doSync
`RFC5905-7.4-3`	For kiss code RATE, the client MUST immediately reduce its polling interval to that server and continue to reduce it each time it receives a RATE kiss code. (§7.4)
	MUST	7.4	positive`no test`no positive test negative`no test`no negative test {gap}: the sync interval is the fixed configured IntervalSec and no kiss code changes it; internal/plugins/ntp/ntp.go run
`RFC5905-7.4-4`	Kiss codes beginning with the ASCII character "X" are for unregistered experimentation and development and MUST be ignored if not recognized. (§7.4)
	MUST	7.4	positive`no test`no positive test negative`no test`no negative test {gap}: no kiss code is inspected (RFC5905-7.4-1), so an X code is not distinguished from DENY, RSTR or RATE; every KoD packet is discarded alike by doSync in internal/plugins/ntp/ntp.go and no test pins the X case
`RFC5905-7.4-5`	The Receive Timestamp and the Transmit Timestamp (set by the server) are undefined when in a KoD packet and MUST NOT be relied upon to have valid values and MUST be discarded. (§7.4)
	MUST NOT	7.4	positive`no test`no positive test negative`no test`no negative test {gap}: doSync in internal/plugins/ntp/ntp.go reads resp.Time, derived from the transmit timestamp, for its absurd-year check before resp.Validate rejects the KoD packet, so a KoD packet can be logged and counted as an absurd timestamp rather than as a kiss
`RFC5905-11.2.3-1`	In this case, the clock is stepped to the correct offset, but since this means all peer data have been invalidated, all associations MUST be reset and the client begins as at initial start. (§11.2.3)
	MUST	11.2.3	positive`no test`no positive test negative`no test`no negative test {gap}: after internal/plugins/ntp/ntp.go::doSync steps the clock it keeps every server's state in w.peers (reach register, offset, delay, stratum) and does not reset the associations to their initial state; no owner ruling names this feature unwanted (ai/META-DECISIONS.md, Goal and scope)

Gaps and untested MUSTs

Requirement	State	Reason
`RFC5905-2-1` All servers and clients who are fully NTPv4-compliant MUST implement the entire suite of algorithms described in this document. (§2)	{gap}, no test	Ze implements the Section 14 SNTP subset, not the entire suite: internal/plugins/ntp/ntp.go::doSync queries each server once per round and keeps its latest sample, with no clock filter, selection, cluster, combine or clock discipline algorithm; no owner ruling names this feature unwanted (ai/META-DECISIONS.md, Goal and scope)
`RFC5905-2-2` Alternative algorithms MAY be used, but their output MUST be identical to the algorithms described in this specification. (§2)	{gap}, no test	internal/plugins/ntp/ntp.go::doSync picks one server with internal/plugins/ntp/state.go::selectBestServer over each server's latest sample, an alternative to the Section 10 and 11 algorithms whose output is not identical to theirs; no owner ruling names this feature unwanted (ai/META-DECISIONS.md, Goal and scope)
`RFC5905-7.4-1` Recipients of kiss codes MUST inspect them and, in the following cases, take these actions: (§7.4)	{gap}, no test	doSync in internal/plugins/ntp/ntp.go discards a stratum-0 response through resp.Validate and logs the error; the kiss code is never read
`RFC5905-7.4-2` For kiss codes DENY and RSTR, the client MUST demobilize any associations to that server and stop sending packets to that server; (§7.4)	{gap}, no test	a server answering DENY or RSTR stays in the server list and is queried again every round; internal/plugins/ntp/ntp.go doSync
`RFC5905-7.4-3` For kiss code RATE, the client MUST immediately reduce its polling interval to that server and continue to reduce it each time it receives a RATE kiss code. (§7.4)	{gap}, no test	the sync interval is the fixed configured IntervalSec and no kiss code changes it; internal/plugins/ntp/ntp.go run
`RFC5905-7.4-4` Kiss codes beginning with the ASCII character "X" are for unregistered experimentation and development and MUST be ignored if not recognized. (§7.4)	{gap}, no test	no kiss code is inspected (RFC5905-7.4-1), so an X code is not distinguished from DENY, RSTR or RATE; every KoD packet is discarded alike by doSync in internal/plugins/ntp/ntp.go and no test pins the X case
`RFC5905-7.4-5` The Receive Timestamp and the Transmit Timestamp (set by the server) are undefined when in a KoD packet and MUST NOT be relied upon to have valid values and MUST be discarded. (§7.4)	{gap}, no test	doSync in internal/plugins/ntp/ntp.go reads resp.Time, derived from the transmit timestamp, for its absurd-year check before resp.Validate rejects the KoD packet, so a KoD packet can be logged and counted as an absurd timestamp rather than as a kiss
`RFC5905-11.2.3-1` In this case, the clock is stepped to the correct offset, but since this means all peer data have been invalidated, all associations MUST be reset and the client begins as at initial start. (§11.2.3)	{gap}, no test	after internal/plugins/ntp/ntp.go::doSync steps the clock it keeps every server's state in w.peers (reach register, offset, delay, stratum) and does not reset the associations to their initial state; no owner ruling names this feature unwanted (ai/META-DECISIONS.md, Goal and scope)

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.

`RFC5905-2-1`

All servers and clients who are fully NTPv4-compliant MUST implement the entire suite of algorithms described in this document. (§2)