Cisco Cisco 2504 Wireless Controller Guía Para Resolver Problemas
It has been discovered that many site surveys are not performed properly or the site survey is omitted
altogether. The intended purpose of this document is to provide guidelines for proper planning, preparation,
and identification of the key items to check through the analysis of a survey report.
altogether. The intended purpose of this document is to provide guidelines for proper planning, preparation,
and identification of the key items to check through the analysis of a survey report.
Prerequisites
Requirements
Cisco recommends that you have knowledge of these topics:
IEEE 802.11 Wireless
•
Wireless LAN Design
•
Components Used
This document is not restricted to specific software and hardware versions.
The information in this document was created from the devices in a specific lab environment. All of the
devices used in this document started with a cleared (default) configuration. If your network is live, make sure
that you understand the potential impact of any command.
devices used in this document started with a cleared (default) configuration. If your network is live, make sure
that you understand the potential impact of any command.
Conventions
Refer to Cisco Technical Tips Conventions for information on document conventions.
Types of Site Surveys
There are three types of surveys: Passive, Active, and Predictive.
Passive Survey
Passive surveys are surveys that are performed with a listen−only mode. The survey client never associates to
the access point (AP). Such surveys can be helpful when you look for rogue devices or you want a good gauge
of downlink RF coverage from the infrastructure devices.
the access point (AP). Such surveys can be helpful when you look for rogue devices or you want a good gauge
of downlink RF coverage from the infrastructure devices.
These can be accomplished with a passive survey:
Identify rogues
•
Locate RF trouble zones quickly
•
Validate final RF setting
•
Perform initial surveys
•
The most significant loss of information with passive surveys is uplink information, Physical (PHY) rate
boundaries and retransmission. PHY rates are generally based on RF signal and noise levels. A passive survey
only reports signal propagation for beacons measured by particular clients. PHY rates can only be measured
by actual data that is sent to and from an AP.
boundaries and retransmission. PHY rates are generally based on RF signal and noise levels. A passive survey
only reports signal propagation for beacons measured by particular clients. PHY rates can only be measured
by actual data that is sent to and from an AP.
Active Survey
Active surveys are performed with the survey client associated to the APs used throughout the survey. When a
client is associated, it performs all the tasks a typical 802.11 client performs, which includes rate shifting data
rates as the RF condition changes and performs retransmissions. Active surveys are commonly used for new
client is associated, it performs all the tasks a typical 802.11 client performs, which includes rate shifting data
rates as the RF condition changes and performs retransmissions. Active surveys are commonly used for new