RFC 9097 §5: IP-Layer Capacity Singleton Metric Definitions

The 17 Requirements of RFC 9097 §5, each quoted from the RFC with its state and the tests that prove it. Conformance explains the states.

RFC9097-5.2-1

Not applicable

This section lists the REQUIRED input factors to specify the metric, beyond those listed in Section 4.

Note: The section adds no Parameters.

RFC9097-5.3-1

Not applicable

This section defines the REQUIRED aspects of the measurable IP-Layer Capacity Metric (unless otherwise indicated) for measurements between specified Source and Destination hosts:

Note: An introduction to the section’s Requirements, each recorded with its own ID; nothing to do beyond them.

RFC9097-5.3-L1

Deviation

Define the IP-Layer Capacity, C(T,dt,PM), to be the number of IP- Layer bits (including header and data fields) in packets that can be transmitted from the Src host and correctly received by the Dst host during one contiguous sub-interval, dt in length.

Note: IP-Layer Capacity; a definition, but the one the Sub-Interval results compute.

Recorded in approximate-upstream-aggregation.

Conformance Records: duplicates-count-as-received, multi-connection-common-grid.

Proving tests:

• crates/udpstp/tests/netns.rs::a_fixed_rate_test_above_the_bottleneck_delivers_its_rate
• crates/udpstp-core/tests/bottleneck.rs::a_fixed_rate_over_the_bottleneck_measures_its_capacity_and_loss
• crates/udpstp-core/tests/bottleneck.rs::a_fixed_rate_under_the_bottleneck_arrives_whole
• crates/udpstp-core/tests/sub_interval_results.rs::a_downstream_client_reports_each_sub_interval_it_received
• crates/udpstp-core/tests/sub_interval_results.rs::over_ipv6_the_headers_are_48_bytes

RFC9097-5.3-2

Tested

Anticipating a Sample of Singletons, the number of sub-intervals with duration dt MUST be set to a natural number m, so that T+I = T + m*dt with dtn+1 - dtn = dt for 1 <= n <= m.

Note: testIntTime / subIntPeriod Sub-Intervals.

Conformance Records: sub-interval-whole-trial-intervals.

Proving tests:

• crates/udpstp-core/tests/sub_interval_results.rs::the_sub_interval_becomes_a_whole_number_of_trial_intervals

RFC9097-5.3-3

Tested

Parameter PM represents other performance metrics (see Section 5.4 below); their measurement results SHALL be collected during measurement of IP-Layer Capacity and associated with the corresponding dtn for further evaluation and reporting.

Note: Per-Sub-Interval statistics (sisSav).

Proving tests:

• crates/udpstp-core/tests/sub_interval_results.rs::each_sub_interval_carries_the_rtt_and_one_way_delay_minimums

RFC9097-5.3-4

Tested

Users SHALL specify the Parameter Tmax as required by each metric’s reference definition.

Note: Tmax.

Conformance Records: tmax-within-the-sub-interval.

Proving tests:

• crates/udpstp-core/tests/sequence_errors.rs::a_load_pdu_later_than_its_sub_interval_stays_lost

RFC9097-5.3-5

Tested

PM represents other performance metrics (see Section 5.4 below); their measurement results SHALL be collected during measurement of IP-Layer Capacity and associated with the corresponding dtn for further evaluation and reporting.

Note: Bullet restating RFC9097-5.3-3.

Proving tests:

• crates/udpstp-core/tests/sub_interval_results.rs::each_sub_interval_carries_the_rtt_and_one_way_delay_minimums

RFC9097-5.3-6

Tested

All sub-intervals MUST be of equal duration.

Note: subIntPeriod is a whole number of Trial Intervals.

Conformance Records: sub-interval-whole-trial-intervals.

Proving tests:

• crates/udpstp-core/tests/sub_interval_results.rs::the_sub_interval_becomes_a_whole_number_of_trial_intervals

RFC9097-5.3-7

Operational

The bit rate of the physical interface of the measurement devices MUST be higher than the smallest of the links on the path whose C(T,I,PM) is to be measured (the bottleneck link).

Note: Deployment of the measurement hosts.

RFC9097-5.3-8

Tested

Measurements according to this definition SHALL use the UDP transport layer.

Proving tests:

• crates/udpstp/tests/loopback.rs::a_client_completes_the_control_phase_over_ipv4_loopback

RFC9097-5.3-9

Tested

The measurement SHOULD use a randomized Source port or equivalent technique, and SHOULD send responses from the Source address matching the test packet Destination address.

Note: The Client’s ports are assigned by the OS from its ephemeral range, not udpstp’s Ephemeral Ports (the Server’s); replies leave from the arrival address (ADR 0007).

Proving tests:

• crates/udpstp/tests/loopback.rs::replies_leave_from_the_address_the_setup_request_arrived_on

RFC9097-5.4-1

Tested

The statistics used to summarize RTD[dtn,dtn+1] MAY include the minimum, maximum, median, mean, and the range = (maximum - minimum).

Proving tests:

• crates/udpstp-core/tests/sub_interval_results.rs::each_sub_interval_carries_the_rtt_and_one_way_delay_minimums

RFC9097-5.4-2

Tested

The statistics used to summarize OWL[dtn,dtn+1] MAY include the count of lost packets and the ratio of lost packets.

Note: Loss Ratio.

Proving tests:

• crates/udpstp-core/tests/sub_interval_results.rs::duplicates_and_reordering_are_reported_apart_from_loss

RFC9097-5.4-3

Tested

Other metrics MAY be measured: one-way reordering, duplication, and delay variation.

Proving tests:

• crates/udpstp-core/tests/sub_interval_results.rs::duplicates_and_reordering_are_reported_apart_from_loss

RFC9097-5.6-1

Tested

The IP-Layer Capacity SHOULD be reported with at least single-Megabit resolution, in units of Megabits per second (Mbps) (which, to avoid any confusion, is 1,000,000 bits per second).

Proving tests:

• crates/udpstp/src/results.rs::a_completed_test

RFC9097-5.6-2

Tested

The related One-Way Loss metric and Round-Trip Delay measurements for the same Singleton SHALL be reported, also with meaningful resolution for the values measured.

Proving tests:

• crates/udpstp/src/results.rs::a_completed_test

RFC9097-5.6-3

Tested

Individual Capacity measurements MAY be reported in a manner consistent with the Maximum IP-Layer Capacity; see Section 9.

Proving tests:

• crates/udpstp/src/results.rs::a_completed_test