USB

USB instance boundary

Records the represented physical extent and the evidence identifying its connectors as USB-related.

1. Does this instance represent a port, plug, cable, adapter or complete connection, and which containing objects are represented elsewhere? boundary
2. What connector family, variant and plug or receptacle form is present at each mating point, and what evidence supports the identification? definition

Path components and mating

Records the proposed or actual route through USB cables, adapters and hubs.

1. Which endpoints, cables, adapters and hubs lie along the intended USB path, in connection order? boundary
2. Do the mating connectors fit as intended without force, and does each intervening component have evidence of supporting the intended use? action

Data support and roles

Records evidence for USB signalling capabilities and supported data roles without deriving them from connector shape.

1. Which USB revisions and signalling modes are supported by each endpoint and intervening component, and where is that support documented? provenance
2. Which endpoint can act as host and which as device for this task, and is any part of the path explicitly limited to power delivery? boundary

Observed USB session

Captures enumeration, exposed functions, active mode and transfer observations for a particular connection session.

1. What device identity and USB functions does the host report after attachment, and which expected functions are absent? measurement
2. What active USB mode, transfer performance and errors are observed, under which test conditions? measurement
3. What evidence supports retrying, changing a path component or investigating an endpoint when enumeration or transfer fails? action

Power path agreement

Records source and sink roles, applicable cable constraints and evidence for the current delivery arrangement.

1. Which component supplies power, which receives it, and what voltage, current and power limits are documented for the endpoints and cable? provenance
2. What supply arrangement or negotiated power contract is active, and how do measured voltage and current compare with it? measurement
3. Can the intended load operate within the evidenced limits of this complete path, or must the agent select another source or cable? action

USB and other mode boundary

Records whether a requested connector-carried function uses USB or requires a separately modelled protocol or mode.

1. Does the requested function use USB data, USB power delivery or another protocol carried through this connector? boundary
2. What evidence shows that both endpoints and every cable or adapter support the required mode and its intended concurrent functions? provenance

USB path serviceability

Records observable connector and cable condition alongside symptoms that may indicate a faulty connection.

1. What contact contamination, deformation, looseness, cable damage, moisture or abnormal heating is observed, and at which component? measurement
2. Do disconnects or errors follow a particular port, cable or adapter during controlled tests with known-working components? measurement
3. Which observations justify stopping use, replacing a component or following the manufacturer's inspection procedure? action

Permitted USB session

Records which USB functions are authorised and what must be checked before enabling or ending their use.

1. Who authorises this connection, and are its reported storage, input, network or other USB functions permitted for the intended task? action
2. If only charging is authorised, what evidence establishes that the selected connection prevents data access? provenance
3. Before disconnection or a role change, what active transfers, mounted storage or power-dependent operations require coordination with the connected device's model? action

Kinds and varieties

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

1. Which of these kinds and varieties hold for the sense of USB this model covers, and on what evidence? provenance

Identifiers and schemes

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

1. Which of these identifiers and schemes hold for the sense of USB this model covers, and on what evidence? provenance

Standards and regulation

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

1. Which of these standards and regulation hold for the sense of USB this model covers, and on what evidence? provenance

Real-world use

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

1. Which of these real-world use hold for the sense of USB this model covers, and on what evidence? provenance

Typical measurements

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

1. Which of these typical measurements hold for the sense of USB this model covers, and on what evidence? provenance

Failure modes and hazards

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

1. Which of these failure modes and hazards hold for the sense of USB this model covers, and on what evidence? provenance

Regional variation

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

1. Which of these regional variation hold for the sense of USB this model covers, and on what evidence? provenance

Neighbouring kinds and how to tell them apart

Reported by the breadth pass; each item needs checking against its source before it becomes normative.

1. Which of these neighbouring kinds and how to tell them apart hold for the sense of USB this model covers, and on what evidence? provenance