Chapter6 Edit Interface/Connection
Configure DSL Controller
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Cisco Router and Security Device Manager 2.5 User’s Guide
OL-4015-12
Line Rate
Choose the DSL line rate for the G.SHDSL port. If you have chosen a 2-wire
connection, you can choose either auto, which configures the interface to
automatically negotiate the line rate between the G.SHDSL port and the DSLAM,
or the actual DSL line rate. The supported line rates are 200, 264, 392, 520, 776,
1032, 1160, 1544, 2056, and 2312.
If you have chosen a 4-wire connection, you must choose a fixed line rate. The
supported line rates for a 4-wire connection are 384, 512, 640, 768, 896, 1024,
1152, 1280, 1408, 1664, 1792, 1920, 2048, 2176, 2304, 2432, 2688, 2816, 2944,
3072, 3200, 3328, 3456, 3584, 3712, 3840, 3968, 4096, 4224, 4352, 4480, and
4608
Note If different DSL line rates are configured at opposite ends of the DSL uplink, the
actual DSL line rate is always the lower rate.
Enable Sound to Noise Ratio Margin
The sound-to-noise ratio margin provides a threshold for the DSL modem to
determine whether it should reduce or increase its power output depending on the
amount of noise on the connection. If you have set the line rate to “auto”, you can
enable this feature to maximize the quality of the DSL connection. Note that you
cannot use this feature if your line rate is fixed. To enable the sound-to-noise ratio
margin, check this check box and choose the ratio margins in the Current and
Snext fields. To disable this feature, uncheck this check box.
Current
Choose the sound-to-noise ratio margin in the form of decibels (dB) on the current
connection. The lower the ratio chosen here, the more noise will be tolerated on
the connection. A lower dB setting will cause the DSL modem to allow more noise
on the line, potentially resulting in a connection of lower quality but higher
throughput. A higher dB setting causes the modem to restrict noise, potentially
resulting in a connection of higher quality but lower throughput.
Snext
Choose the Self near-end crosstalk (Snext) sound-to-noise ratio margin in the
form of decibels.