Chapter 6: Configuring DSL Parameters

•Annex-Bfor operating conditions typically found in the European implementation of G.shdsl. This is the default mode for the MM701G modem.

•Auto for automatically negotiates the Annex A or B standard by which this modem, and the device to which this modem is attached, can operate. This is the default mode for the MM702G modem.

•Annex-B_ANFPfor operating conditions that include the Annex B standard with Access Network Frequency Plan Pulse Spectral Density (PSD) mask.

•Auto_ANFP for automatically negotiating the Annex A or B standard with Access Network Frequency Plan Pulse Spectral Density (PSD) mask.

Startup Margin

The target signal-to-noise margin, in decibels, that the modem must achieve with a BER of 10-7or better to successfully complete synchronization. The default margin value is 6 dB. A lower margin may result in a higher data rate, but it can increase noise on the line. Possible values are -10dBthrough 10dB, or to completely Disable the margin.

Data Rate (kbps)

Data rate determines the maximum transmission rate, in kilobits per second, up to which the modem can negotiate and synchronize with another device (modem or a DSLAM) to which it is attached. When the Bit Rate Mode (page 62) is set to Fixed, the range of values are (ADC modems comply with the standard G.shdsl data rate range):

•for the MM702G modem, 384 kbps to 4608 kbps, in 128 kbps increments (default value is 4608)

•for the MM701G modem, 192 kbps to 2304 kbps, in 64 kbps increments

Rates down to 64 kbps are supported only when operating in single-pair, point-to-point mode with another ADC modem. (see Chapter 7, “Implementing a Point-to-Point LAN Extension”).

When the Bit Rate Mode (page 62) is set to Adaptive for an MM701G (Adaptive is MM701G default value) or for an MM702G set to Single Wire Pair Mode only (see below), this field is automatically set to Adaptive. An MM702G in Dual Wire Pair Mode cannot be used in Adaptive Bit Rate Mode.

Wire Pair Mode

Indicates whether the G.shdsl modem is operating in a two-wire mode (Single) or a four-wire mode (Dual). For the MM701G modem, Single mode is the only setting available. For the MM702G modem, you can select either Single or Dual mode and Dual mode is the default.

MM701G and MM702G User Manual

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