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Cisco Aironet Wireless LAN Adapters Installation and Configuration Guide for MS-DOS
OL-1744-02
Chapter 1 Overview Coverage Options
Coverage Options
The system architecture o pt io ns of t he wireless station and a cce s s p oi nt s p rovid e for a variety of
coverage alternatives a nd flexibility. The syste m c a n be designed to provi de a wide coverage a r ea with
minimal overlap (Figure 1-5) or coverage with heavy overlap (Figure1-6). The latter improves system
performance and protec tio n ag ain st dow n tim e i n the event of a component fa il ur e.

Minimal Overlap Coverage

By arranging the access p oint s so th at th e overlap in coverage area is minim iz ed , a la rge area can be
covered with minimal sys tem co s t (Fi gu r e 1 - 5). T he total bandwidth availa bl e t o e ach mobile station
depends on the amou nt of data each mobi le sta tion needs to trans f er an d the number of stat ions located
in each cell. Seamless r oaming is supported as a m obile station moves in and out of range of each access
point, thereby maintaining a co nstant connection to the wir ed LAN. Each access point (and adapter) must
be configured with the same SSID to pr ov id e the roaming ca pa bility.
Figure1-5 Minimal Overlap Coverage Op tion

Heavy Overlap Coverage

By arranging the access p oints so that the overlap in coverag e area is nearly maximize d, a large number
of mobile stations can be supported in the same wireless infrastructure (Figure1-6). However, units in
overlapping coverage areas on t he sam e frequency will detect ad ja cen t c ell traffic and delay
transmissions that would cau se collisions. This reduces th e ag gregat e r ad i o sy s t em t hr o ug h put. H eavy
cell overlap is not recommended for maximum system throughput. Due to the redundancy in coverage
overlap, system access is n ot lo s t if an a cce ss point fails. If the access po in t fai ls, the station
automatically roams to an o pe r ati on al acce s s po in t. With this sy s te m ar ch ite cture, all access points and
PC Card units must be configured with the same SSID.
Wired LAN
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