Cisco Cisco ACE Application Control Engine Module 白書
Wireless LAN Design Guide for High Density
Client Environments in Higher Education
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In any Wi-Fi design, the effects of CCI can be limited by isolating the individual cells from one another through the use of
non-overlapping channels and natural environment attenuation (walls, ceilings, file cabinets and cubes). We would not place two
APs on the same channel directly next to one another intentionally. In a normal design, the environment and distances we are
covering generally permit adequate coverage without a lot of CCI. But in a high-density network design, the distances are going
to be constrained and propagation will be good, as such cell coupling and resulting CCI will become much more likely.
non-overlapping channels and natural environment attenuation (walls, ceilings, file cabinets and cubes). We would not place two
APs on the same channel directly next to one another intentionally. In a normal design, the environment and distances we are
covering generally permit adequate coverage without a lot of CCI. But in a high-density network design, the distances are going
to be constrained and propagation will be good, as such cell coupling and resulting CCI will become much more likely.
Design Point #3: Choose a High Minimum Data Rate to Support Increased Efficiency, Lower
Duty Cycle, and Reduce the Effective Size of the Resulting Cell
CCI is not only an issue that will be faced in aggregating channels within the high-density deployment but something that must
be kept in mind regarding existing deployments of surrounding areas. Lecture halls and classrooms tend to be co-located in the
same facility, so overall design must be considered.
be kept in mind regarding existing deployments of surrounding areas. Lecture halls and classrooms tend to be co-located in the
same facility, so overall design must be considered.
is an excellent resource that presents CCI and best practices for Wi-Fi
implementation. As an older document, it does not cover the extreme densities found in a high-density WLAN.
The Cisco WCS and controllers make monitoring co-channel interference and identifying the responsible AP or APs a fairly
straightforward exercise. Cisco Radio Resource Management (RRM) algorithms are centralized and are a network-wide resource
that continuously evaluates every single AP in the RF network to determine its relationship to every other AP in the system.
It does this through the use of over the air (OTA) measurements and observations. Knowing how well other APs can hear a
selected AP is a very useful feature when considering or planning a high-density WLAN deployment. Using Cisco WCS, it is
possible to evaluate how well APs can hear one another―independent of a channel. This information is shown in a graphic display
that shows not only how APs are effecting each other on a particular map, but also how other APs that are not on the map can
impact a WLAN as well.
straightforward exercise. Cisco Radio Resource Management (RRM) algorithms are centralized and are a network-wide resource
that continuously evaluates every single AP in the RF network to determine its relationship to every other AP in the system.
It does this through the use of over the air (OTA) measurements and observations. Knowing how well other APs can hear a
selected AP is a very useful feature when considering or planning a high-density WLAN deployment. Using Cisco WCS, it is
possible to evaluate how well APs can hear one another―independent of a channel. This information is shown in a graphic display
that shows not only how APs are effecting each other on a particular map, but also how other APs that are not on the map can
impact a WLAN as well.