netsys NV-720 Series, User Manual

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NV-720S ADSL2+/VDSL2 Wi-Fi USER’S MANUAL Ver. A.2
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3. Symptom: VDSL Link cannot be established.
Cause: VDSL setting failure or phone cable length is over the specification limit.
Solution:
3.1 Please make sure that the phone wire must be connected between CO side and NV-720S
(CPE) when both are power on. CO side will do link speed function depending on phone wire
length, therefore if CO side can’t detect NV-720S (CPE) over phone wire while both power on,
this will cause the link to fail.
3.2 Please check the phone wire, we recommend using 24-26 gauge twisted pair cables without
rust.
3.3 Please reinsert power when changing the cable length or link time over 3 minutes.
Note:
The phone wire must meet CAT 3 standard or above and without clustering, otherwise it will cause
more cross talk, reducing the DSL power driver.
4. Question: What is VDSL2? (Only reference)
Answer:
Very-high-speed digital subscriber line 2 (VDSL2) is an access technology that exploits the existing
infrastructure of copper wires that were originally deployed for traditional telephone service. It can
be deployed from central offices, from fiber-optic connected cabinets located near the customer
premises, or within buildings. It was defined in standard ITU-T G.993.2 finalized in 2005.
VDSL2 was the newest and most advanced standard of digital subscriber line (DSL) broadband wire
line communications. Designed to support the wide deployment of triple play services such as voice,
video, data, high definition television (HDTV) and interactive gaming, VDSL2 was intended to enable
operators and carriers to gradually, flexibly, and cost-efficiently upgrade existing xDSL infrastructure.