AirLive X.USB - Manual (Page 30)

5. Wireless Network Glossary
25 X.USB User’s Manual
Preamble Type
Preamble are sent with each wireless packet transmit for transmission status. Use
the long preamble type for better compatibility. Use the short preamble type for
better performance
Rate Control
Ethernet switches' function to control the upstream and downstream speed of an
individual port. Rate Control management uses "Flow Control" to limit the speed of a
port. Therefore, the Ethernet adapter must also have the flow control enabled. One
way to force the adapter's flow control on is to set a port to half-duplex mode.
RADIUS (Remote Authentication Dial-In User Service)
An authentication and accounting system used by many Internet Service Providers
(ISPs). When you dial in to the ISP, you must enter your username and password.
This information is passed to a RADIUS server, which checks that the information is
correct, and then authorizes access to the ISP system. Radius typically uses port
1812 and port 1813 for authentication and accounting port. Though not an official
standard, the RADIUS specification is maintained by a working group of the IETF.
Receiver Sensitivity
Receiver sensitivity means how sensitive is the radio for receiving signal. In general;
the slower the transmission speed, the more sensitive the radio is. The unit for
Receiver Sensitivity is in dB; the lower the absolute value is, the higher the signal
strength. For example, -50dB is higher than -80dB.
RJ-45
Standard connectors for Twisted Pair copper cable used in Ethernet networks.
Although they look similar to standard RJ-11 telephone connectors, RJ-45
connectors can have up to eight wires, whereas telephone connectors have only
four.