Supported

RFC 4486 - Subcodes for BGP Cease NOTIFICATION Message

Every requirement this repository extracted from RFC 4486, 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 ways100.0%1 of 1 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 1 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 1 binding obligations

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

No test at all0.0%0 of 1 binding obligations

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

Proven by a recorded break0.0%0 of 4 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 MUSTs1of 11 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 1 gated MUSTs

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

The 4 shares marked as a part above are the whole of the 1 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	ok	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	Supported
Enrolment	Enrolled
Requirements	11
Gated MUST-level	1
Obligations that bind Ze	1
Not applicable, so out of scope	0
Declared gaps	0
Gated with no test	0
Nightly-only evidence	0
Test tags	4
Tagged units	4
Recorded audit verdicts	0
Discrimination records	0
Summary	`rfc/short/rfc4486.md`
Requirement shard	`rfc/requirements/rfc4486.md`
RFC text	`rfc/full/rfc4486.txt`

Enrolment

Enrolled: Subcodes for BGP Cease NOTIFICATION Message: one MUST-level requirement, RFC4486-4-1 -- terminating a peering because the prefix count exceeded a locally configured upper bound MUST send a NOTIFICATION with Error Code Cease and Error Subcode "Maximum Number of Prefixes Reached". Both polarities are proven over the reactor's prefix-limit path (internal/component/bgp/reactor/session_prefix.go:399 decides, :448 builds the NOTIFICATION with message.NotifyCease and message.NotifyCeaseMaxPrefixes): positive in TestPrefixExceedTeardown, and negative in TestPrefixWarningThreshold, where a peer at the warning threshold but below the maximum receives no NOTIFICATION at all -- so the Cease is bound to the termination and not merely to a counter moving. test/plugin/prefix-maximum-enforce.ci pins the same bytes on the wire (error code 06, subcode 01, plus the AFI/SAFI/count Data field of RFC4486-4-10). The other ten rows in section 4 are SHOULD, RECOMMENDED or MAY and are not gated.

What the public ledger says

Status: Supported

What the ledger says is covered

The subcode catalog for error code 6, subcodes 1 to 8 (internal/component/bgp/message/notification.go). Also max-prefix teardown, retry backoff, and the operator reset paths. Enrolled 2026-07-30. Its sole MUST-level requirement is proven in both polarities. That requirement binds subcode 1 to the teardown a prefix-maximum breach causes. test/plugin/prefix-maximum-enforce.ci asserts the bytes on the wire, including the optional AFI/SAFI/upper-bound Data field of Figure 1. The ten advisory statements of section 4 are bound per line in rfc/short/rfc4486.md.

What the ledger says remains:

No tracked gap in current source anchors.

Coverage

Bucket	Count	What it counts
Positive and negative tests	1	one part of the gated population
Annotated instead of tested	0	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	1	every gated MUST falls in exactly one bucket above

Positive and negative tests (1): RFC4486-4-1

Requirements

Requirement	Level	Section	Tests
`RFC4486-4-1`	If a BGP speaker decides to terminate its peering with a neighbor because the number of address prefixes received from the neighbor exceeds a locally configured upper bound (as described in [BGP-4]), then the speaker MUST send to the neighbor a NOTIFICATION message with the Error Code Cease and the Error Subcode "Maximum Number of Prefixes Reached" (§4)
	MUST	4 - Subcode Usage	positive`unit/verifyTestPrefixExceedTeardown` negative`unit/verifyTestPrefixWarningThreshold` positive`functional/verifyprefix-maximum-enforce.ci`
`RFC4486-4-2`	If a BGP speaker decides to administratively shut down its peering with a neighbor, then the speaker SHOULD send a NOTIFICATION message with the Error Code Cease and the Error Subcode "Administrative Shutdown" (§4)
	SHOULD	4 - Subcode Usage	positive`no test`no positive test negative`no test`no negative test
`RFC4486-4-3`	If a BGP speaker decides to de-configure a peer, then the speaker SHOULD send a NOTIFICATION message with the Error Code Cease and the Error Subcode "Peer De-configured" (§4)
	SHOULD	4 - Subcode Usage	positive`no test`no positive test negative`no test`no negative test
`RFC4486-4-4`	If a BGP speaker decides to administratively reset the peering with a neighbor, then the speaker SHOULD send a NOTIFICATION message with the Error Code Cease and the Error Subcode "Administrative Reset" (§4)
	SHOULD	4 - Subcode Usage	positive`no test`no positive test negative`no test`no negative test
`RFC4486-4-5`	If a BGP speaker decides to disallow a BGP connection (e.g., the peer is not configured locally) after the speaker accepts a transport protocol connection, then the BGP speaker SHOULD send a NOTIFICATION message with the Error Code Cease and the Error Subcode "Connection Rejected" (§4)
	SHOULD	4 - Subcode Usage	positive`no test`no positive test negative`no test`no negative test
`RFC4486-4-6`	If a BGP speaker decides to administratively reset the peering with a neighbor due to a configuration change other than the ones described above, then the speaker SHOULD send a NOTIFICATION message with the Error Code Cease and the Error Subcode "Other Configuration Change" (§4)
	SHOULD	4 - Subcode Usage	positive`no test`no positive test negative`no test`no negative test
`RFC4486-4-7`	If a BGP speaker decides to send a NOTIFICATION message with the Error Code Cease as a result of the collision resolution procedure (as described in [BGP-4]), then the subcode SHOULD be set to "Connection Collision Resolution" (§4)
	SHOULD	4 - Subcode Usage	positive`no test`no positive test negative`no test`no negative test
`RFC4486-4-8`	An implementation SHOULD impose an upper bound on the number of consecutive automatic retries (§4)
	SHOULD	4 - Subcode Usage	positive`no test`no positive test negative`no test`no negative test
`RFC4486-4-9`	It is RECOMMENDED that a BGP speaker behave as though the DampPeerOscillations attribute [BGP-4] were true for this peer when re-trying a BGP connection after the speaker receives a Cease NOTIFICATION message with a subcode of "Administrative Shutdown", "Peer De-configured", "Connection Rejected", or "Out of Resources" (§4)
	RECOMMENDED	4 - Subcode Usage	positive`no test`no positive test negative`no test`no negative test
`RFC4486-4-10`	The message MAY optionally include the Address Family information [BGP-MP] and the upper bound in the "Data" field, as shown in Figure 1 (§4)
	MAY	4 - Subcode Usage	positive`unit/verifyTestPrefixNotificationDataCarriesTheConfiguredUpperBound` negative`no test`no negative test
`RFC4486-4-11`	If a BGP speaker runs out of resources (e.g., memory) and decides to reset a session, then the speaker MAY send a NOTIFICATION message with the Error Code Cease and the Error Subcode "Out of Resources" (§4)
	MAY	4 - Subcode Usage	positive`no test`no positive test negative`no test`no negative test

Gaps and untested MUSTs

RFC 4486 declares no gap, and every gated MUST it carries has a test bound to it.

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.

`RFC4486-4-1`

If a BGP speaker decides to terminate its peering with a neighbor because the number of address prefixes received from the neighbor exceeds a locally configured upper bound (as described in [BGP-4]), then the speaker MUST send to the neighbor a NOTIFICATION message with the Error Code Cease and the Error Subcode "Maximum Number of Prefixes Reached" (§4)

Audit verdict: not audited: no reader has judged these tests

Polarity	Test	Kind and tier	Proof state
negative	`TestPrefixWarningThreshold`	unit/verify	unproven
positive	`TestPrefixExceedTeardown`	unit/verify	unproven
positive	`prefix-maximum-enforce.ci`	functional/verify	unproven

`RFC4486-4-10`

The message MAY optionally include the Address Family information [BGP-MP] and the upper bound in the "Data" field, as shown in Figure 1 (§4)

Audit verdict: not audited: no reader has judged these tests

Polarity	Test	Kind and tier	Proof state
positive	`TestPrefixNotificationDataCarriesTheConfiguredUpperBound`	unit/verify	unproven

Extraction sign-off

Field	Value
Reviewer	ze-implement agent, spec-rfcgate-4-ledger phase 6
Signed off	2026-07-30
Register	rfc2119
Source	rfc/full/rfc4486.txt
Source fingerprint	ee862bf55c82959b
Record	rfc/extraction/rfc4486.json
Mapped sentences	1
Declined as scope	0
Relocated to a spec, which Ze OWES	0
Unclassified	0

Sections

Section	Name	Sites	Disposition	Reason
`front`	not stated	0	skipped (front-matter)	Title block, Status of this Memo, copyright notice and Abstract. The Abstract restates section 1 word for word and states no obligation.
`1`	Introduction	0	walked	Introduction. Says what the document defines and that it 'also recommends' a backoff mechanism. The recommendation itself is stated normatively in section 4 and is captured there as RFC4486-4-9.
`2`	not stated	0	walked	Specification of Requirements: the RFC 2119 key-words paragraph. It tells a reader how to read the other sections and binds no speaker, which is why the derivation excludes it from the site inventory.
`3`	Subcode Definition	0	walked	Subcode Definition. The registry table assigning subcodes 1 to 8 to their symbolic names. A value assignment, not a directive: the obligation to USE each value is in section 4.
`4`	Subcode Usage	1	walked	Subcode Usage. The only normative section. Its one capitalised MUST is the site below; the remaining ten sentences are SHOULD, RECOMMENDED or MAY and are captured as RFC4486-4-2 through RFC4486-4-11.
`5`	IANA Considerations	0	skipped (iana)	IANA Considerations. Defines subcodes 1 to 8 in the registry and names the process for future assignments. Binds IANA, not a speaker.
`6`	Security Considerations	0	walked	Security Considerations. One sentence: the extension does not change BGP's underlying security issues. No countermeasure is directed at a speaker.
`7`	Acknowledgements	0	skipped (acknowledgements)	Acknowledgements.
`8`	References heading	0	skipped (references)	References heading.
`8.1`	Normative References: RFC 2119, RFC 4271, RFC 4760	0	skipped (references)	Normative References: RFC 2119, RFC 4271, RFC 4760.
`8.2`	Informative References: RFC 2434, RFC 4020	0	skipped (references)	Informative References: RFC 2434, RFC 4020.

Excluded sentences

The walk over RFC 4486 declined no sentence: every site it found is mapped to a requirement.

Superseded

No document obsoletes RFC 4486, so its obligations are stated where they were written.