Troubleshooting the Wireless AP
If you have multiple wireless access points (APs) and are unable to connect or authenticate with one of them, you might have a problem with that specific wireless AP. This section describes the common troubleshooting tools of wireless APs and the common problems of connecting and authenticating with a wireless AP.
Wireless AP Troubleshooting Tools
Although the set of troubleshooting tools for wireless APs varies with each manufacturer and with each model, some of the more common troubleshooting tools are the following:
- Panel indicators
- Site survey software
- SNMP support
- Diagnostics
These tools are described in the following sections. Consult your wireless AP documentation for information about the set of troubleshooting tools provided with your wireless AP.
Panel IndicatorsMost wireless APs have one or more indicators, which are status lights that are visible on the housing of the wireless AP, from which you can obtain a quick assessment of the wireless AP's hardware status. For example, you might see the following:
- An indicator to show that the wireless AP has electrical power.
- An indicator to show general operation status. For example, the indicator might show whether the wireless AP is associated with any wireless clients.
- An indicator to show wireless network traffic. This indicator might blink for each frame received on the wireless network.
- An indicator to show data collisions. If the blinking of this indicator seems excessive, evaluate the performance of the link by using the methods suggested by the wireless AP vendor.
- An indicator to show wired network traffic. This indicator might blink for each frame received on the wired network.
Alternatively, the wireless AP might have a liquid crystal display (LCD) panel that shows icons that indicate its current status. Consult your wireless AP documentation for information about panel indicators and their interpretation.
Site Survey SoftwareSite survey software, which you use during the deployment of wireless APs to determine their optimal placement, is typically installed on a wireless-capable laptop computer from a CD-ROM provided by the wireless AP or wireless network adapter vendor.
As described in the section "Deploying Wireless APs," the site survey software is used to determine the coverage volume and where the data rate changes for each wireless AP.
If wireless clients cannot connect to a specific wireless AP, use the site survey software to perform a site survey for that wireless AP. There might have been a change in the devices that create interference and objects that interfere with signal propagation since the original site survey and AP placement was done.
SNMP SupportMany wireless APs include a Simple Network Management Protocol (SNMP) agent with support for the following SNMP Management Information Bases (MIBs):
- IEEE 802.11 MIB
- IEEE 802.1 PAE (Port Access Entity) MIB
- SNMP Management MIB (described in RFC 1157)
- SNMP MIB II (described in RFC 1213)
- Bridge MIB (described in RFC 1286)
- Ethernet Interface MIB (described in RFC 1398)
- IETF Bridge MIB (described in RFC 1493)
- Remote Monitoring (RMON) MIB (described in RFC 1757)
- RADIUS Client Authentication MIB (described in RFC 2618)
The SNMP agent on the wireless AP can be used in conjunction with your existing SNMPbased network management infrastructure to configure your wireless APs, set trap conditions, and monitor loads on your wireless APs.
DiagnosticsDiagnostics for wireless APs can be in the following forms:
- Diagnostic facilities that are available through the main wireless AP configuration program, such as a Windows program provided on the wireless AP vendor product CD-ROM or a series of Web pages.
- Diagnostic facilities that are available through a command-line tool or facility, such as terminal access to the wireless AP.
The exact diagnostic facilities of a wireless AP vary from one wireless AP to another; however, the purpose of the diagnostics is to ensure that the wireless AP is operating properly (from a hardware standpoint) and to validate its current configuration.
In this tutorial:
- IEEE 802.11 Wireless Networks
- Support for IEEE 802.11 Standards
- Wireless Security
- WPA
- Planning and Design Considerations
- Wireless Authentication Modes
- Intranet Infrastructure
- Wireless AP Placement
- Authentication Infrastructure
- Wireless Clients
- Windows Vista Wireless Policy
- Windows XP Wireless Policy
- Command-Line Configuration
- PKI
- 802.1X Enforcement with NAP
- Deploying Protected Wireless Access
- Configuring Active Directory for Accounts and Groups
- Deploying Wireless APs
- Configuring Wireless Clients
- Configuring and Deploying Wireless Profiles
- Maintenance for a Protected Wireless
- Troubleshooting Wireless Connections
- Network Diagnostics Framework Support for Wireless Connections
- Wireless Diagnostics Tracing
- NPS Event Logging
- Troubleshooting the Windows Wireless Client
- Troubleshooting the Wireless AP
- Common Wireless AP Problems
- Troubleshooting the Authentication Infrastructure
- Troubleshooting Certificate-Based Validation
- Troubleshooting Password-Based Validation