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Q6: Can VC-202 compatible with VC-202A?
A6: Currently NO. Although VC-202 (prole 12a) and VC-202A
(prole 17a) is base on ITU-T G.993.2 VDSL2, but with
different Proles, so far they are not compatible with each
other.
Q7: What is SNR and what’s the effect?
A7: In analog and digital communications, Signal-to-Noise Ratio,
often written SNR, is a measure of signal strength relative
to background noise. The ratio is usually measured in deci-
bels (dB).
In digital communications, the SNR will probably cause a
reduction in data speed because of frequent errors that
require the source (transmitting) computer or terminal to
resend some packets of data. SNR measures the quality of
a transmission channel over a network channel. The greater
the ratio, the easier it is to identify and subsequently isolate
and eliminate the source of noise.
Generally speaking, the higher SNR value gets better line
quality, but lower performance.
Q8: What is band plan and what’s the effect?
A8: VDSL2 denes multiple band plans and conguration modes
(proles) to allow asymmetric and symmetric services in
the same binder (by designated frequency bands) for the
transmission of upstream and downstream signals. User
has the ability to select xed band plan. When Symmetric
is selected that provides better downstream performance,
when Asymmetric is selected that provides better upstream
performance.