DOCSIS 3.0 Downstream SC-QAM Channel Statistics¶

Provides DOCSIS 3.0 Downstream SC-QAM Channel Configuration And Signal-Quality Metrics (Power, RxMER, Codeword Counters).

Endpoint¶

POST /docs/if30/ds/scqam/chan/stats

Request¶

Use the SNMP-only format: Common → Request
TFTP parameters are not required.

Response¶

This endpoint returns the standard envelope described in Common → Response (mac_address, status, message, data).

Abbreviated Example¶

{
  "mac_address": "aa:bb:cc:dd:ee:ff",
  "status": 0,
  "message": null,
  "data": [
    {
      "index": 52,
      "channel_id": 32,
      "entry": {
        "docsIfDownChannelId": 32,
        "docsIfDownChannelFrequency": 639000000,
        "docsIfDownChannelWidth": 6000000,
        "docsIfDownChannelModulation": "qam256",
        "docsIfDownChannelInterleave": "taps32Increment4",
        "docsIfDownChannelPower": 1.1,
        "docsIfSigQUnerroreds": 260152637,
        "docsIfSigQCorrecteds": 351,
        "docsIfSigQUncorrectables": 0,
        "docsIfSigQMicroreflections": 3,
        "docsIfSigQExtUnerroreds": 129109307889,
        "docsIfSigQExtCorrecteds": 351,
        "docsIfSigQExtUncorrectables": 0,
        "docsIf3SignalQualityExtRxMER": 403
      }
    },
    {
      "index": 53,
      "channel_id": 31,
      "entry": {
        "docsIfDownChannelId": 31,
        "docsIfDownChannelFrequency": 633000000,
        "docsIfDownChannelWidth": 6000000,
        "docsIfDownChannelModulation": "qam256",
        "docsIfDownChannelInterleave": "taps32Increment4",
        "docsIfDownChannelPower": 0.8,
        "docsIfSigQUnerroreds": 89334852,
        "docsIfSigQCorrecteds": 460,
        "docsIfSigQUncorrectables": 0,
        "docsIfSigQMicroreflections": 3,
        "docsIfSigQExtUnerroreds": 128938490104,
        "docsIfSigQExtCorrecteds": 460,
        "docsIfSigQExtUncorrectables": 0,
        "docsIf3SignalQualityExtRxMER": 409
      }
    },
    { "...": "other channels elided" }
  ]
}

Channel Fields¶

Field	Type	Description
`index`	int	SNMP table index (OID instance) for this channel’s row in the CM table.
`channel_id`	int	DOCSIS downstream SC-QAM logical channel ID.

Entry Fields¶

Field	Type	Units	Description
`docsIfDownChannelId`	int	—	Channel ID (mirrors logical ID).
`docsIfDownChannelFrequency`	int	Hz	Center frequency.
`docsIfDownChannelWidth`	int	Hz	Channel width.
`docsIfDownChannelModulation`	string	—	Modulation name (e.g., `qam256`).
`docsIfDownChannelInterleave`	string	—	Interleaver mode name (e.g., `taps32Increment4`).
`docsIfDownChannelPower`	float	dBmV	Received RF power level.
`docsIfSigQUnerroreds`	int	cw	Unerrored codewords (base counter).
`docsIfSigQCorrecteds`	int	cw	Corrected codewords (base counter).
`docsIfSigQUncorrectables`	int	cw	Uncorrectable codewords (base counter).
`docsIfSigQMicroreflections`	int	—	Micro-reflections indicator (implementation-specific scale).
`docsIfSigQExtUnerroreds`	int64	cw	Unerrored codewords (extended 64-bit), if supported.
`docsIfSigQExtCorrecteds`	int64	cw	Corrected codewords (extended 64-bit), if supported.
`docsIfSigQExtUncorrectables`	int64	cw	Uncorrectable codewords (extended 64-bit), if supported.
`docsIf3SignalQualityExtRxMER`	int	0.1 dB	RxMER in tenths of dB (e.g., `403` → 40.3 dB).

Notes¶

docsIfDownChannelModulation is normalized to a modulation name (e.g., qam256).
Prefer extended (64-bit) counters when available to avoid rollover on high-traffic channels.
Metrics such as RxMER, Uncorrectables, And Micro-Reflections Are Critical For Diagnosing RF Impairments.
docsIfDownChannelInterleave is normalized to an interleaver mode name.