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10. Operational Considerations for the Measurement Method

Dieser Abschnitt bewahrt den RFC-Text zu UDPSTP, einschliesslich One-Way IP Capacity metrics, Control and Data phases, Load and Status Feedback PDUs, KDF/HMAC authentication, optional checksum handling, IANA registries und security considerations.

Originaler RFC-Text

10.  Operational Considerations for the Measurement Method

The architecture of the method requires two cooperating hosts
operating in the roles of Src (test packet sender) and Dst
(receiver), with a measured path and return path between them.

The nominal duration of a measurement interval at the Destination,
parameter testIntTime, MUST be constrained in a production network,
since this is an active test method and it will likely cause
congestion on the Src to Dst host path during a test.

It is RECOMMENDED to locate test endpoints as close to the intended
measured link(s) as practical. The testing operator MUST set a value
for the MaxHops parameter, based on the expected path length. This
parameter can keep measurement traffic from straying too far beyond
the intended path.

It is obviously counterproductive to run more than one independent
and concurrent test (regardless of the number of flows in the test
stream) when attempting to measure the maximum capacity on a single
path. The number of concurrent, independent tests of a path SHALL be
limited to one.

The load rate adjustment algorithm's scope is limited to helping
determine the Maximum IP-Layer Capacity in the context of an
infrequent, diagnostic, short-term measurement. It is RECOMMENDED to
discontinue non-measurement traffic that shares a subscriber's
dedicated resources while testing: measurements may not be accurate,
and throughput of competing elastic traffic may be greatly reduced.

See Section 8 of [RFC9097] for a discussion of the Method of
Measurement beyond purely operational aspects.

10.1. Notes on Interface Measurements

Additional measurements may be useful in specific circumstances. For
example, interface byte counters measured by a client at a
residential gateway are possible when the client application has
access to an interface that sees all traffic to/from a service
subscriber's location. Adding a byte counter at the client for
download or upload directions could be used to measure total traffic
and possibly detect when non-test traffic is present (and using
capacity). The client may not have the CPU cycles available to count
both the interface traffic and IP-Layer Capacity simultaneously, so
this form of diagnostic measurement may not be possible.