Experimental

RFC 3954 - Cisco Systems NetFlow Services Export Version 9

Every requirement this repository extracted from RFC 3954, 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 ways40.0%2 of 5 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 reason40.0%2 of 5 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 5 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 8 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 MUSTs9of 21 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 scope4of 9 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 all20.0%1 of 5 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 5 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	Experimental
Enrolment	Enrolled
Requirements	21
Gated MUST-level	9
Obligations that bind Ze	5
Not applicable, so out of scope	4
Declared gaps	1
Gated with no test	0
Nightly-only evidence	0
Test tags	8
Tagged units	8
Recorded audit verdicts	0
Discrimination records	0
Summary	`rfc/short/rfc3954.md`
Requirement shard	`rfc/requirements/rfc3954.md`
RFC text	`rfc/full/rfc3954.txt`

Enrolment

Enrolled: NetFlow Services Export Version 9 (ze as a v9 exporter): nine MUST-level requirements. Four are met: x-1 (never send a Data FlowSet before its Template) and x-8 (the sequence number is cumulative per observation domain) carry positive+negative tags; x-3 (network byte order) and x-9 (a Template ID is constant for the process lifetime) are {single-polarity: positive}. x-2 (refresh templates on both a time interval and a packet-count interval) is {gap}: ze refreshes on a configurable time interval only, with no packet-count-based interval. x-4, x-5, x-6, x-7 are {not-applicable}: they are NetFlow v9 collector requirements and ze is an exporter only. Disclosed in the docs/features/rfc-status.md RFC 3954 row.

What the public ledger says

Status: Experimental

What the ledger says is covered

Flow export templates and records over UDP (exporter): no Data FlowSet before its Template, cumulative per-observation-domain sequence numbers, network byte order, constant Template IDs
tests bound per requirement in rfc/requirements/rfc3954.md.

What the ledger says remains:

Template refresh is time-interval-based only, with no packet-count-based refresh interval (RFC3954-x-2 gap). ze is an exporter only; the v9 collector requirements are not applicable.

Coverage

Bucket	Count	What it counts
Positive and negative tests	2	one part of the gated population
Annotated instead of tested	7	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	9	every gated MUST falls in exactly one bucket above

Positive and negative tests (2): RFC3954-x-1, RFC3954-x-8

Annotated instead of tested (7): RFC3954-x-2, RFC3954-x-3, RFC3954-x-4, RFC3954-x-5, RFC3954-x-6, RFC3954-x-7, RFC3954-x-9

Requirements

Requirement	Level	Section	Tests
`RFC3954-x-1`	Exporter MUST NOT send a Data FlowSet without having sent the corresponding Template FlowSet in a previous or the same export packet (Template Lifecycle)
	MUST	x	positive`unit/verifyTestWriteExportPacketWithTemplate` negative`unit/verifyTestExporterSendsTemplateBeforeData`
`RFC3954-x-2`	Exporter MUST periodically refresh templates using both time-based and packet-count-based intervals, both configurable (Template Lifecycle)
	MUST	x	positive`no test`no positive test negative`no test`no negative test {gap}: ze refreshes NetFlow v9 templates on a time interval only (internal/plugins/flowexport/exporter.go:192-199, config template-refresh seconds); it has no packet-count-based template-refresh interval, so the conjoined time-and-packet-count refresh requirement is only partly met
`RFC3954-x-3`	All binary integer values MUST be coded in network byte order (big-endian) (Encoding Rules)
	MUST	x	positive`unit/verifyTestNetflow9DataFlowSet` positive`unit/verifyTestNetflow9Header` negative`no test`no negative test {single-polarity}: ze only ENCODES NetFlow v9 (exporter-only, internal/plugins/flowexport/netflow9); every multi-octet field is written big-endian via binary.BigEndian and there is no decode or wrong-endianness code path to reject, so only the positive can be tested
`RFC3954-x-4`	Collector MUST use the FlowSet ID to find the correct template for decoding (Validation)
	MUST	x	positive`no test`no positive test negative`no test`no negative test {not-applicable}: this is a NetFlow v9 collector requirement (map a Data FlowSet ID to its template); ze is a v9 exporter only (internal/plugins/flowexport/netflow9) with no v9 decode/collect code path
`RFC3954-x-5`	Collector MUST use the Length field to determine the position of the next FlowSet record (Encoding Rules)
	MUST	x	positive`no test`no positive test negative`no test`no negative test {not-applicable}: collector requirement (use FlowSet Length to find the next FlowSet); ze does not collect v9
`RFC3954-x-6`	Collector MUST accept padding in Data FlowSets and Options Template FlowSets (Validation)
	MUST	x	positive`no test`no positive test negative`no test`no negative test {not-applicable}: collector requirement (accept padding); ze does not collect v9 (its exporter does emit 4-octet padding at internal/plugins/flowexport/netflow9/data.go:38-44)
`RFC3954-x-7`	Collector MUST override an existing template when a new definition arrives for the same Template ID (Template Lifecycle)
	MUST	x	positive`no test`no positive test negative`no test`no negative test {not-applicable}: collector requirement (override a template on redefinition); ze does not collect v9
`RFC3954-x-8`	Sequence Number MUST be a cumulative counter per observation domain (Wire Format)
	MUST	x	positive`unit/verifyTestNetflow9FlowSeqNumPerPacket` negative`unit/verifyTestNetflow9SeqNumNotAdvancedOnSendError`
`RFC3954-x-9`	Template ID MUST remain constant for the life of the NetFlow process on the exporter (Template Lifecycle)
	MUST	x	positive`unit/verifyTestNetflow9FlowTemplate` positive`unit/verifyTestNetflow9Template` negative`no test`no negative test {single-polarity}: ze's NetFlow v9 template IDs are compile-time constants (CounterTemplateID=256 in internal/plugins/flowexport/netflow9/template.go, FlowTemplateID=257 and FlowTemplateID6=258 in flow_template.go) that are never reassigned for the life of the process, so there is no ID-change code path to test negatively
`RFC3954-x-10`	Exporter SHOULD insert padding to 4-octet alignment using zeros (Encoding Rules)
	SHOULD	x	positive`no test`no positive test negative`no test`no negative test
`RFC3954-x-11`	Exporter SHOULD send templates at an accelerated rate after configuration changes or clock changes (Template Lifecycle)
	SHOULD	x	positive`no test`no positive test negative`no test`no negative test
`RFC3954-x-12`	Collector SHOULD use (exporter IP, Source ID) to separate different export streams (Wire Format)
	SHOULD	x	positive`no test`no positive test negative`no test`no negative test
`RFC3954-x-13`	Collector SHOULD buffer data records when the matching template has not yet been received (Validation)
	SHOULD	x	positive`no test`no positive test negative`no test`no negative test
`RFC3954-x-14`	Collector SHOULD use Sequence Number to detect missing packets (Wire Format)
	SHOULD	x	positive`no test`no positive test negative`no test`no negative test
`RFC3954-x-15`	Exporter SHOULD NOT reuse a Template ID after configuration changes until the process restarts (Template Lifecycle)
	SHOULD NOT	x	positive`no test`no positive test negative`no test`no negative test
`RFC3954-x-16`	Export path SHOULD be a dedicated link or provisioned to handle burst rate without drops (Transport Considerations)
	SHOULD	x	positive`no test`no positive test negative`no test`no negative test
`RFC3954-x-17`	Exporter MAY send template-only packets (no data) to pre-populate the collector (Template Lifecycle)
	MAY	x	positive`no test`no positive test negative`no test`no negative test
`RFC3954-x-18`	Exporter MAY export flows prematurely due to internal constraints (memory pressure, counter wrap) (Exporter Implementation)
	MAY	x	positive`no test`no positive test negative`no test`no negative test
`RFC3954-x-19`	Exporter MAY include multiple template records in a single Template FlowSet (Template FlowSet)
	MAY	x	positive`no test`no positive test negative`no test`no negative test
`RFC3954-x-20`	Exporter MAY send templates and data in the same packet (Template Lifecycle)
	MAY	x	positive`no test`no positive test negative`no test`no negative test
`RFC3954-x-21`	Exporters MAY use reserved field type IDs for vendor-specific fields (Reserved Fields)
	MAY	x	positive`no test`no positive test negative`no test`no negative test

Gaps and untested MUSTs

Requirement	State	Reason
`RFC3954-x-2` Exporter MUST periodically refresh templates using both time-based and packet-count-based intervals, both configurable (Template Lifecycle)	{gap}, no test	ze refreshes NetFlow v9 templates on a time interval only (internal/plugins/flowexport/exporter.go:192-199, config template-refresh seconds); it has no packet-count-based template-refresh interval, so the conjoined time-and-packet-count refresh requirement is only partly met
`RFC3954-x-4` Collector MUST use the FlowSet ID to find the correct template for decoding (Validation)	no test	no test carries this requirement id; annotated {not-applicable}: this is a NetFlow v9 collector requirement (map a Data FlowSet ID to its template); ze is a v9 exporter only (internal/plugins/flowexport/netflow9) with no v9 decode/collect code path
`RFC3954-x-5` Collector MUST use the Length field to determine the position of the next FlowSet record (Encoding Rules)	no test	no test carries this requirement id; annotated {not-applicable}: collector requirement (use FlowSet Length to find the next FlowSet); ze does not collect v9
`RFC3954-x-6` Collector MUST accept padding in Data FlowSets and Options Template FlowSets (Validation)	no test	no test carries this requirement id; annotated {not-applicable}: collector requirement (accept padding); ze does not collect v9 (its exporter does emit 4-octet padding at internal/plugins/flowexport/netflow9/data.go:38-44)
`RFC3954-x-7` Collector MUST override an existing template when a new definition arrives for the same Template ID (Template Lifecycle)	no test	no test carries this requirement id; annotated {not-applicable}: collector requirement (override a template on redefinition); ze does not collect v9

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.

`RFC3954-x-1`

Exporter MUST NOT send a Data FlowSet without having sent the corresponding Template FlowSet in a previous or the same export packet (Template Lifecycle)