ZyXEL Communications MSC1024G Series User Manual page 223

Figure 131 ADSL Port Setup: Advanced: Option Mask
The following table describes the fields in this screen.
Table 83 ADSL Port Setup: Advanced: Option Mask
LABEL
All
Disable Trellis
Disable Reed
Solomon
Disable
Upstream/
Downstream
Bitswap
Disable 1-bit
Constellation
Disable Transmit
Windowing
Disable S=0.5
Support(ADSL1
Only)
Disable G.lite
Rate Limit
(ADSL1 Only)
Current Option
mask is:
Apply
Cancel
MSC1000G/1024G/1224G Series User's Guide
DESCRIPTION
Use the check boxes to disable individual features. Use the All check box to select
every feature check box.
Trellis encoding helps to reduce the noise in ADSL transmissions. Trellis may
reduce throughput but it makes the connection more stable.
Reed-Solomon performs transmission error correction.
Bit swapping allows the system to respond to noise on a tone by sending it's data
on another tone. The subscriber (ATU-R) equipment must also support this in
order for it to work.
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.
Transmit windowing is only available with ADSL2+.
0.5 support maps two Reed-Solomon code words into one data frame (instead of
one) to increase the maximum G.dmt transmission rate.
Disabling the G.lite rate limit allows the G.lite upstream transmission rate to be
greater than 512 Kbps.
Selecting or clearing feature check boxes adjusts the current option mask
displayed at the bottom of the screen.
Click Apply to save the changes in this screen to the system's volatile memory.
The system loses these changes if it is turned off or loses power, so use the
Config Save on the navigation panel and then the Save button to save your
changes to the non-volatile memory when you are done configuring.
Click Cancel to close the screen without saving your changes.
Chapter 11 Subscriber Port Setup Screens
223