ZyXEL Communications VMG3926-B10A - Page 79

Chapter 6 Broadband
VMG3926-B10A User’s Guide
79
Figure 26 Network Setting > Broadband > Advanced
The following table describes the labels in this screen.
Table 13 Network Setting > Broadband > Advanced
LABEL DESCRIPTION
PhyR US Enable or disable PhyR US (upstream) for upstream transmission to the WAN. PhyR US
should be enabled if data being transmitted upstream is sensitive to noise. However,
enabling PhyR US can decrease the US line rate. Enabling or disabling PhyR will require the
CPE to retrain. For PhyR to function, the DSLAM must also support PhyR and have it
enabled.
PhyR DS Enable or disable PhyR DS (downstream) for downstream transmission from the WAN.
PhyR DS should be enabled if data being transmitted downstream is sensitive to noise.
However, enabling PhyR DS can decrease the DS line rate. Enabling or disabling PhyR will
require the CPE to retrain. For PhyR to function, the DSLAM must also support PhyR and
have it enabled.
Bitswap
SRA Enable or disable Seamless Rate Adaption (SRA). Select Enable to have the VMG
automatically adjust the connection’s data rate according to line conditions without
interrupting service.
ADSL
Modulation
PTM over
ADSL:
Select Enable to use PTM over ADSL. Since PTM has less overhead than ATM, some ISPs
use this for better performance.
G.Dmt: ITU G.992.1 (better known as G.dmt) is an ITU standard for ADSL using discrete multitone
modulation. G.dmt full-rate ADSL expands the usable bandwidth of existing copper
telephone lines, delivering high-speed data communications at rates up to 8 Mbit/s
downstream and 1.3 Mbit/s upstream.
G.lite : ITU G.992.2 (better known as G.lite) is an ITU standard for ADSL using discrete multitone
modulation. G.lite does not strictly require the use of DSL filters, but like all variants of
ADSL generally functions better with splitters.