Network Speed Test Result Interpreter

Inspectable records

Ledger state

The current ledger marks this instrument verified clean within the source-bound verification corpus.

Area

Computing & Information

Tranche

tranche-7

Evidence ID

t7-057

Ledger rows

1

No ledger note is attached.

Review findings

The core comparison idea is reasonable as a guideline calculator, and the transfer arithmetic is correct under the stated decimal-unit assumptions. The instrument remains NEEDS_REVIEW because the actual lookup-table contents, provenance, date, ping algorithm, video-call mapping, file-size set, and zero-bandwidth behavior are unspecified. No interpolation is used in these vectors; therefore no bracketing table rows are applicable.

Formula and scope findings

• The stated transfer_time=size/bandwidth formula is incomplete unless file size is converted to megabits and bandwidth is explicitly treated as decimal Mbps; for decimal gigabytes, time_seconds=(size_GB*8000)/bandwidth_Mbps.
• The specification does not define the exact bundled lookup rows, service versions, publication dates, comparison operators, or whether thresholds are minimums or recommended values.
• Video-call quality cannot be determined reliably from download and upload speed plus ping alone; jitter, packet loss, route stability, codec, resolution, participant count, and service-specific requirements are omitted.
• Ping has no specified interpretation or quality bands, so any ping-based checklist would require an additional documented guideline table.
• The output definition does not specify which common file sizes are reported or whether transfer times include protocol overhead, congestion, Wi-Fi limitations, or sustained-throughput efficiency.

Unit assumptions

• Bandwidth inputs are decimal megabits per second (Mbps), where 1 Mbps=1,000,000 bits/s.
• File sizes in these vectors are decimal gigabytes (GB), where 1 GB=1,000,000,000 bytes=8,000 megabits.
• Ping is in milliseconds (ms).
• A use-case threshold is supported when the relevant measured speed is greater than or equal to the table threshold.
• Video-call quality uses the lower of download and upload speed against the symmetric table requirement.
• The illustrative lookup values are general guidance, not guarantees; service-specific and dated source metadata must be bundled with the production instrument.

Boundary hardening

BREAK_CLAIMED · SELF_FLAGGED

A zero download rate causes transfer-time division by zero and requires rejection or an explicit undefined result. The lookup results also depend on exact threshold inclusivity, and throughput and ping unit ambiguity can change the reported transfer time or video-call assessment.

Errata and corrections

No applied erratum is attached to this unique-name record.

Inspectable example

4 review vectors are recorded. One source-bound sample is shown below.

{
  "inputs": {
    "download_mbps": 25,
    "upload_mbps": 10,
    "ping_ms": 20,
    "file_size_gb": 1
  },
  "expected_outputs": {
    "supported_use_cases": {
      "streaming": [
        "SD",
        "HD",
        "4K/UHD"
      ],
      "video_call": "HD",
      "ping_quality": "excellent"
    },
    "transfer_time_seconds": 320,
    "transfer_time_human": "5 min 20 s"
  },
  "reference_data": {
    "streaming_thresholds_mbps": {
      "SD": {
        "download_mbps": 3,
        "source_convention": "widely tabulated standard value; Netflix-published minimum guidance, bundled snapshot required"
      },
      "HD": {
        "download_mbps": 5,
        "source_convention": "widely tabulated standard value; Netflix-published minimum guidance, bundled snapshot required"
      },
      "4K/UHD": {
        "download_mbps": 15,
        "source_convention": "widely tabulated standard value; Netflix-published minimum guidance, bundled snapshot required"
      }
    },
    "video_call_thresholds_mbps": {
      "standard": {
        "download_mbps": 1.5,
        "upload_mbps": 1.5,
        "source_convention": "widely tabulated standard value; published video-conferencing guidance, bundled snapshot required"
      },
      "HD": {
        "download_mbps": 3,
        "upload_mbps": 3,
        "source_convention": "widely tabulated standard value; published video-conferencing guidance, bundled snapshot required"
      }
    },
    "ping_bands_ms": {
      "excellent_max": 50,
      "source_convention": "widely tabulated standard value; general latency guideline"
    },
    "table_comparison": "greater than or equal to threshold"
  },
  "working": "Streaming: 25>=3, so SD is supported; 25>=5, so HD is supported; 25>=15, so 4K/UHD is supported. Video call: min(25,10)=10 Mbps; 10>=3, so HD is supported. Ping: 20<=50 ms, so ping quality is excellent. Transfer: 1 GB*8,000=8,000 megabits; 8,000/25 Mbps=320 s; 320 s=5 min 20 s."
}

Related workflows

No source-defined multi-instrument workflow membership is recorded.

Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

• VERIFIED_LEDGER.json · VERIFIED_CLEAN
• evidence-tranche7/tranche7-results.json
• BOUNDARY_HAZARD_CATALOG.json