Manage DSL

Standard Annex

Type 2 then select one of the following Annexes:

•1—Annex-Afor operating conditions typically found in the North American implementation of G.shdsl

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

•3—Autofor automatically negotiating 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.

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

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

Startup Margin

Type 3 then select a number from 1 to 21 for possible values between -10dBthrough 10dB, or select 22 to completely Disable the 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.

Data Rate (kbps)

Type 4 then select a data rate (number 1 through 34) which 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 123) 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 123) 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.

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MM701G and MM702G User Manual