ZyXEL Communications PLA-402 v3, Руководство пользователя

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Chapter 6 The OS X Configuration Utility
PLA-402 v3 User’s Guide
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Avg. Bits/Carrier This field displays the average number of bits transferred over
the connection measured in Mbps. This represents the physical
rate of data transmission (the PHY rate) which includes not only
the files sent on your powerline, but also line overhead required
to manage your network, such as error correction bits.
The PHY rate is the clearest indicator of the quality of your line.
• If the PHY rate is close to the HomePlug AV maximum data
transfer rate, then the quality of this section of the line is
very high, with very little attenuation.
• If the PHY rate varies between the maximum level and a
lower level (such as 60 Mbps), there is noise on this section
of your powerline. Attenuation is not a factor.
• If the PHY rate is steady at a lower level (such as 80 Mbps),
this is caused by attenuation and not noise on this section of
your powerline.
Avg. SNR/Carrier This field displays the average Signal to Noise Ratio (SNR)
measured in dB. Use this to check the amount of noise on this
part of your powerline network. The higher the number the
better the connection quality.
Noise on your powerline coaxial network is usually caused by
household appliances running on your powerline coaxial
network. The motor of a refrigerator can create electrical
interference. A cell/mobile phone recharger which rapidly
alternates between on and off can also generate noise. Poor
cable quality and installation can also cause noise. To identify
causes of noise on your network, disconnect an appliance
connected on this part of your powerline coaxial network and
observe whether this reduces the Signal-to-Noise ratio.
Avg. Attentuation/
Carrier This field displays the average attenuation measured in dB.
Attenuation is the reduction in strength of a signal as it travels
over a transmission line. Use this field to check the reduction in
the strength of the signal between two devices.
Attenuation may vary considerably across a powerline coaxial
network as line conditions also vary. A typical level of
attenuation may be 40 dB, but may reach over 70 dB,
depending on line quality and distance.
A main cause of attenuation is the power requirements of
appliances on your electrical circuit. Powerline traffic near an
appliance such as a refrigerator may be affected by attenuation
more than on other sections of your powerline coaxial network.
Avg. Output Power/
Carrier This field shows the average power produced by the source
device. Power levels should be constant and limited by the
output power standard of your country. Unusually high output
power levels may damage your device.
Clear Statistics Click this button to reset all counters in this screen to zero.
Close Click this button to close this window.
Table 11 Link Information (continued)
LABEL DESCRIPTION