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MSAP2000 AAMS User’s Guide
Discrete Multi-Tone (DMT) modulation divides up a line's bandwidth into tones.
This screen displays the number of bits transmitted for each tone. This can be
used to determine the quality of the connection, whether a given sub-carrier loop
has sufficient margins to support ADSL transmission rates, and possibly to
determine whether certain specific types of interference or line attenuation exist.
Refer to the ITU-T G.992.1 recommendation for more information on DMT.
The better (or shorter) the line, the higher the number of bits transmitted for a
DMT tone. The maximum number of bits that can be transmitted per DMT tone is
15.
The bit allocation contents are only valid when the link is up.
In the screen shown, the downstream channel is carried on tones 48 to 255 and
the upstream channel is carried on tones 16 to 31 (space is left between the
channels to avoid interference).
Figure 38 Line Data
