Toshiba TEC Corporation GN1041 Manuale Utente

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2. Appendix
GN-1041 Operator’s Manual — Glossary
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Roaming
This term has the same meaning as roaming for a portable phone or PHS.  The AP is in 
the role commonly called the “antenna/base station” for the phone or PHS, and the user 
unit is in the role of the phone itself.
Router
A device for relaying between LAN's.  The router determines data addresses by the 
combination of a network address assigned to the network and an individual computer 
address.  Used particularly in medium-scale and larger LAN systems with very large 
number of clients, to reduce traffic (congestion) on communication lines.
RSSI (Receive Signal Strength Indication)
A numeric indicator of incoming signal strength.
RTS (Request To Send)
In communication via AP, transmission is controlled by CSMA/CA plus RTS.  In RTS, a 
wireless terminal asks the AP if it is able to transmit, and only transmits after an OK-to-
send acknowledgement signal is returned.  This serves to avoid unnecessary collisions 
when hidden terminals exist because hidden terminals cannot transmit.
Spectrum Diffusion Transmission
A method of transmission in which signals that are normally transmitted over a given 
limited frequency band undergo narrow band modulation (primary modulation), then 
again diffuse modulation (secondary modulation) to intentionally diffuse the signal over 
a broad frequency spectrum.