Multicell Configuration - Black Box LW0050A Manual

PRO 11 SERIES WIRELESS ETHERNET
5.1.3 M C
ULTICELL
Areas congested by many users and a heavy traffic load may require a multicell
structure. In a multicell structure, several Access Points are installed in the same
location. Each Access Point has the same coverage area, thereby creating a
common coverage area that increases aggregate throughput. Any workstation in
the overlapping area can associate and communicate with any Access Point
covering that area.
To set up a multicell:
1. Calculate the number of Access Points needed as follows. Multiply the number
of active users by the required throughput per user, and divide the result by 1.5
Mbps (which is the net throughput supported by collocated Access Points).
Consider the example of 5 active stations, each requiring 0.5-Mbps throughput.
The calculation is 5 × 0.5/1.5 = 1.7. Two Access Points should be used. This
method is accurate only for the first few Access Points.
The aggregate throughput of the common coverage area is equal to the
number of collocated Access Points multiplied by the throughput of each
individual Access Point, minus a certain amount of degradation caused by the
interference among the different Access Points.
2. Install several Access Points in the same location a few meters from each other
so they cover the same area. Be sure to position the Access Points at the highest
points possible.
3. To allow roaming and redundancy, configure all Access Points and station
adapters to the same ESSID.
4. To improve collocation and performance, configure all Access Points to
different hopping sequences of the same hopping set.
5. Install Station Adapters or PCMCIA Adapters in workstations.
6. Make sure the Load Sharing option is activated. Stations will automatically
associate with an Access Point that is less loaded and provides better signal
quality.
It isn't necessary at this point to connect the Access Points to an
Ethernet backbone, since Access Points continuously transmit signals
(beacon frames) whether they are connected to an Ethernet backbone or
not.
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ONFIGURATION
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