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CHAPTER 1: Introduction
Network connection is maintained while roaming between overlapping cell
coverage areas. Transmission and reception can be continued while moving at
high speed with no data-packet loss or duplication.
The PCMCIA Adapter is available in two models:
• With two integrated omnidirectional retractable antennas (LW0054A).
• With two external-antenna connector ports (LW0059A).
1.4 Pro 11 Functional Description
1.4.1 Q
UICK
R
EVIEW OF
E
THERNET
Standard Ethernet LAN stations are wired to a common bus. When one of the
stations sends a message, it assigns a destination address to the message and sends
the message on the bus. All stations on the bus “hear” the message, but only the
station with the proper address processes the message.
1.4.2 S
TARTUP
P
ROCEDURE
When wireless units (other than Access Points) start up, they scan the frequencies
for an Access Point. If an active Access Point is in range, the units synchronize with
it. The addresses associated with the units are registered in the Access Point (the
registration process is different for each unit type). From then on, the units can
send and receive messages to and from the wired LAN.
1.4.3 A
CCESS
P
OINT
The Access Point is connected to a wired Ethernet LAN, and it keeps a list of
known stations on its wireless side. When an Access Point “hears” a message that is
destined for a wireless station, the Access Point forwards the message wirelessly to
the station. If the message has a destination address that the Access Point does not
recognize, the Access Point ignores the message.
The Access Point continuously “listens” for wireless messages as well. When the
Access Point “hears” a wireless message destined for another wireless unit, it relays
the message directly to the wireless unit without forwarding the message to the
wired LAN. When the Access Point “hears” a wireless message whose destination is
not on the wireless LAN, it forwards the message to the wired LAN. Messages
cannot be sent directly between wireless stations without an Access Point to relay
the message.
Summary of Contents for LW0050A
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