Cisco Cisco Catalyst 6500 Series 7600 Series Wireless Services Module (WiSM) Weißbuch
Wireless LAN Design Guide for High Density
Client Environments in Higher Education
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Under Floor Mounting
Mounting APs under the floor with the intent of radiating through to the users can provide a great deal of attenuation. This in
theory will work and will allow the creation of more pico cells within a given environment. However, based on experience, the
number of facilities where this has proven practical remains small. Mounting beneath the floor should not be ignored as an option
and it should be investigated. The occasional corner case where this is a viable option can be quite useful to the design. The
RF density of the floor and access available will be the limiting factors. Pre-stressed concrete floors or floors containing a lot of
reinforcing materials are generally not suitable. It is also important to consider the reflective potential of the floor material and
where this will reflect to in the rest of the infrastructure.
theory will work and will allow the creation of more pico cells within a given environment. However, based on experience, the
number of facilities where this has proven practical remains small. Mounting beneath the floor should not be ignored as an option
and it should be investigated. The occasional corner case where this is a viable option can be quite useful to the design. The
RF density of the floor and access available will be the limiting factors. Pre-stressed concrete floors or floors containing a lot of
reinforcing materials are generally not suitable. It is also important to consider the reflective potential of the floor material and
where this will reflect to in the rest of the infrastructure.
Bringing it all Together
Consider a high-density WLAN deployment in two rooms that together are 26,000 square feet, Figure 15. Room A has seating
for 1450 and room B has seating for 1500. Both rooms are separated by a double air-gaped temporary wall, which provides
good RF attenuation. The design goal is to provide coverage for the participants, assuming a 25 percent duty cycle. The focus
is on 2.4 GHz coverage, since this is the critical resource for most all PDAs and several tablet models. 5 GHz exhibits similar
advantages in the denser room and room B had far more happy 5 GHz users simply because propagation distances were less
overall between AP and clients.
for 1450 and room B has seating for 1500. Both rooms are separated by a double air-gaped temporary wall, which provides
good RF attenuation. The design goal is to provide coverage for the participants, assuming a 25 percent duty cycle. The focus
is on 2.4 GHz coverage, since this is the critical resource for most all PDAs and several tablet models. 5 GHz exhibits similar
advantages in the denser room and room B had far more happy 5 GHz users simply because propagation distances were less
overall between AP and clients.
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Room A has a total of six APs deployed. Two APs have directional antennas used from the sides, two APs with internal antennas
are positioned at the front, one internal antenna AP is positioned at the rear of the room, and one internal AP is floor mounted to
fill in for a shadow behind a pillar in the room. Power levels are set to 11 dBm and result in good coverage levels for the room.
Minimum data rates are set to 9 Mbps. BandSelect and Cisco ClientLink are enabled.
fill in for a shadow behind a pillar in the room. Power levels are set to 11 dBm and result in good coverage levels for the room.
Minimum data rates are set to 9 Mbps. BandSelect and Cisco ClientLink are enabled.
Room B has a total of 12 APs deployed. Eight are positioned under the seating in the room. Two APs are at the rear and two APs
are in the front of the room. Power levels were reduced to 5 dBm. Minimum data rates were held at 12 Mbps, BandSelect and
Cisco ClientLink were enabled.
are in the front of the room. Power levels were reduced to 5 dBm. Minimum data rates were held at 12 Mbps, BandSelect and
Cisco ClientLink were enabled.