Select transmission medium – Televes Coaxdata 1Gbps-HDTV COAX+PLC 1ETH+1SFP User Manual
Page 10
CoaxManager
™
User Guide
10
Select Transmission medium
Sets device transmission medium
•
Hybrid Coax+PLC
: This option indicates that operation mode is hybrid, where devices
communicate via PLC and Coax. The
medium swich
on front of device
must be on the left
and power LED is set to
orange color
.
•
Only Coax
: In this mode of operation only coaxial is used as communication medium. The
medium swich
on front of device
must be on the right
and power LED is set to
green color
.
•
Enable Hidden Node
: This option changes medium access mechanism of the devices.
Typically medium access method is based on CSMA (carrier sense medium access) listening
and checking medium is avaliable. Devices access to medium when no one else is transmitting.
This mechanism, however, requires that all of the devices can listen all transmissions of other
devices connected to the network. Depending on the coaxial network in which the system is
implemented, there may not listen slaves of other slaves transmissions due to a high isolation of
distribution outlets (> 100dB) and CSMA access mechanism in not valid.
Enable Hidden Node
option replaces medium access contention for a token-based system, where
slaves transmit only when the master gives them permission. For this mechanism to work properly, all
devices on the network must have this feature enabled.
With this feature modems access to the medium only when they have permission to do so, providing
better performance in environments where the insulation between slaves is very high. Since the devices
have to get the token for access to the medium, there is a 20% reduction in the total thoughput system.
This feature is enabled by default when user select Coaxial Medum to transmit. Disable only when
isolation between slaves is a known low value.
EN