ZyXEL Communications MSC1000G Series, User Manual

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Chapter 9 Subscriber Port Setup Screens
Management Switch Card User’s Guide
235
9.8.5 VDSL Port Setup Advanced: VDSL Optionmask Screen
Click the Optionmask link in the advanced VDSL Port Setup screen to display a pop-up screen as
shown. Use this screen to enable features on a port for advanced troubleshooting. ADSL features
are included because the VDSL line card supports ADSL fallback.
Figure 144
VDSL Port Setup: Advanced: Optionmask
The following table describes the fields in this screen.
Table 103
VDSL Port Setup: Advanced: Optionmask
LABEL DESCRIPTION
All Use the check boxes to disable individual features. Use the All check box to select every
feature check box.
Disable Trellis Trellis encoding helps to reduce the noise in ADSL transmissions. Trellis may reduce
throughput but it makes the connection more stable.
Disable Reed
Solomon Reed-Solomon performs transmission error correction.
Disable
Upstream/
Downstream
Bitswap Bit swapping allows the system to respond to noise on a tone by sending data on another
tone. The subscriber (ATU-R) equipment must also support bit swapping in order for this
feature to work.
Disable 1-bit
Constellation 1-bit constellation allows the system to send individual bits over DMT tones that can only
support one bit. This allows the connection to use as many of the tones as possible.
Disable Transmit
Windowing Transmit windowing is only available with ADSL2+.
Disable S=0.5
Support(ADSL1
Only) 0.5 support maps two Reed-Solomon code words into one data frame (instead of one) to
increase the maximum G.dmt transmission rate.
Reserved At the time of writing, this feature is not available.
Enable Nitro This allows ATM header compression for greater bandwidth efficiency.