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6193-5201
How a Link connection is lost
The Access Point refreshes the link status with a Client every time a message is received
from that Client. If nothing is received from a Client for a period of 120 seconds, the
Access Point sends a “link-check” message. If there is no response to the link-check a
De-authenticate message is sent and the link is dropped.
A Client monitors beacons from an Access Point to determine whether the link is still
present. If the Client can no longer receive beacons from the AP, the AP is considered to
be out-of-range and the link is dropped. Whenever a Client is not connected to an AP, it
will cyclically scan all available channels for a suitable AP.
Roaming
Clients may also roam between Access Points. If a Client receives a beacon from an AP
with a stronger signal than the current AP (providing SSID is the same and capability
information are compatible), it may disconnect from the first AP and establish a link with
the second AP. This functionality permits a client to have mobility whilst maintaining a link
with the most suitable AP.
LED Indication
The following table details the status of the indicating LEDs on the front panel under
normal
operating conditions.
LED Indicator
Condition
Meaning
OK GREEN
Normal
Operation
OK
RED
Supply voltage too low.
Radio RX
GREEN flash
Radio receiving data
Radio RX
RED flash
Weak radio signal
Radio TX
Flash
Radio Transmitting
Radio LINK
On
On when a radio communications link is established
Radio LINK
Off
Communications failure or radio link not established
Radio LINK
GREEN flash
RED flash
Serial Port Receiving
CTS low
LAN
ON
Link Established on Ethernet port
LAN
Flash
Activity on Ethernet port.
Serial
GREEN flash
RS-232 Serial Port Activity
Serial
RED flash
RS-485 Serial Port Activity
DIO
On
Digital Output ON
or
Input is grounded.
DIO
Off
Digital Output OFF
and
Input is open circuit.
The Ethernet RJ45 port incorporates two indication LEDs. The LINK LED comes on
when there is a connection on the Ethernet port, and will blink off briefly when activity is
detected on the Ethernet Port. The 100MB LED indicates that the connection is at
100 MBit/Sec. The 100MB LED will be off for 10MB/Sec connection.
Other conditions indicating a fault are described in Chapter Six
Troubleshooting
.