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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SNR is commonly quoted for electrical signals, it can be applied to any form of signal (such as
isotope levels in an ice core or biochemical signaling between cells). The ratio is usually measured
in decibels(dB)
The signal-to-noise ratio, the bandwidth, and the channel capacity of a communication channel are
connected by the Shannon–Hartley theorem.
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.
6. Symptom:
Connected the CO Router with CPE Router within 300 meters RJ-11 phone cable got only less than
10 Mbit/s.
Cause:
Some testing programs which are based on TCP/IP protocols such as FTP, Iperf, NetIQ, the testing
bandwidth outcome will be limited by TCP window size.
Solution:
We recommend testing VDSL2 bandwidth using Smartbits® equipment or IPERF program. The
TCP window size must be set to max. 64k, the parameter as iperf –c server IP address –i 1 –t 50 –w
65535 for client side.
7. Question:
I just bought a Netsys NV-720S to replace my Quest DSL modem for my home. I was told any VDSL2
modem would work and give me higher communication speeds. It doesn’t get me internet when
hooked up. All lights come on but no Link light. Is this the complete wrong application for this unit?
Answer:
Please note NV-720S is a remote side (CPE side), it must be connected to the CO side to work.
Tone mode, Band profile and band plan settings must be compatible with each other, if not; access