Microwave Data Systems iNET 900 Series, Руководство пользователя

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162 MDS iNET 900 Series User’s Guide MDS 05-2806A01, Rev. E.1
PING—Packet INternet Groper. Diagnostic message generally used to
test reachability of a network device, either over a wired or wireless net-
work.
Point-Multipoint System—A radio communications network or
system designed with a central control station that exchanges data with
a number of remote locations equipped with terminal equipment.
Poll—A request for data issued from the host computer (or master PLC)
to a remote radio.
Portability—A station is considered connected when it has successfully
authenticated and associated with an access point. A station is consid-
ered authenticated when it has agreed with the access point on the type
of encryption that will be used for data packets traveling between them.
The process of association causes a station to be bound to an access
point and allows it to receive and transmit packets to and from the access
point. In order for a station to be associated it must first authenticate
with the access point. The authentication and association processes
occur automatically without user intervention.
Portability refers to the ability of a station to connect to an access point
from multiple locations without the need to reconfigure the network set-
tings. For example, a remote transceiver that is connected to an access
point may be turned off, moved to new site, turned back on, and,
assuming the right information is entered, can immediately reconnect to
the access point without user intervention.
PLC—Programmable Logic Controller. A dedicated microprocessor
configured for a specific application with discrete inputs and outputs. It
can serve as a host or as an RTU.
Remote—A transceiver in a network that communicates with an asso-
ciated Access Point.
Remote Terminal Unit—See RTU.
RFI—Radio Frequency Interference
Roaming—A station's ability to automatically switch its wireless con-
nection between various access points as the need arises. A station may
roam from one access point to another because the signal strength or
quality of the current access point has degraded below what another
access point can provide. When two access points are co-located for
redundancy, roaming allows the stations to switch between the access
points to provide a robust network. Roaming may also be employed in
conjunction with Portability where the station has been moved beyond
the range of the original access point to which it was connected. As the
station comes in range of a new access point, it will switch its connec-
tion to the stronger signal. Roaming refers to a station's logical, not nec-