Cisco Aironet 1240 AG Series

Daylight Saving Time For Cisco Wireless Networking Platforms

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Cisco ® wireless networking platforms include the following:

• Access points-unified and autonomous

– Indoor-Cisco Aironet® 1000, 1100, 1130, 1200, 1230, and 1240 Series

– Outdoor-Cisco Aironet 1300, 1400, and 1500 Series

• Client adapters

• Antennas

• Standalone wireless LAN controllers: Cisco 2000, 2100, 4100 and 4400 Series

• Integrated wireless LAN controllers for Cisco switches and routers:

– Cisco Catalyst® 6500 Series Wireless Services Module (WiSM)

– Cisco Catalyst 3750 Series Integrated Wireless LAN Controllers

– Wireless LAN Controller for Cisco 2800 and 3800 Series Integrated Services Routers

• Wireless LAN management

– Unified management

· Cisco Wireless Control System (WCS)

· Cisco Wireless Location Appliance

– Autonomous management

· CiscoWorks Wireless LAN Solution Engine (WLSE)

This product bulletin summarizes how each of the above platforms addresses Daylight Saving Time (DST) requirements. Full DST support implies:

• The platforms automatically advance or revert the local time at the start and end of DST without user intervention, or

• The platforms accept manual configuration of the start and end date and time of DST

In cases where the platforms do not support DST, the workaround is described in detail.

DST Change

The U.S. Energy Policy Act of 2005 made changes to the DST implementation for the United States; these changes go into effect in March 2007.


(a) Amendment.-Section 3(a) of the Uniform Time Act of 1966 (15 U.S.C. 260a(a)) is amended-

(1) By striking "first Sunday of April" and inserting "second Sunday of March"; and

(2) By striking "last Sunday of October" and inserting "first Sunday of November".

For Cisco wireless networking platforms with full DST support, the local time will correctly change on the second Sunday of March and first Sunday of November in 2007.

Access Points

Unified-The start and end of DST does not affect Cisco lightweight access points. The lightweight access points does not require local time for operation. All logs and reports are generated and maintained by the wireless LAN controllers.
Autonomous-Cisco autonomous access points run Cisco IOS ® Software, and DST is fully supported. The user must upgrade to Cisco IOS Software Release 12.3(11)JA1 or 12.3(8)JEA1 or later for both releases..

Client Adapters

Cisco client adapter functions are not affected by the start and end of DST.


Cisco antenna functions are not affected by the start and end of DST.

Wireless LAN Controllers

Cisco wireless LAN controllers do not currently support DST. At the start and end of DST, the user must manually reset the time to reflect the local time zone. The command syntax is identical for all Cisco wireless LAN controllers. There are two workarounds-the user can either reset the system time, or change the offset hours relative to Coordinated Universal Time (UTC).
First, to verify system time and date, type the following using CLI:
>Show time

1. To reset the system time and date, enter the following command, inserting the correct month, day, year, hours, minutes, and seconds:

>config time mm/dd/yy hh:mm:ss

2. To change the offset hours from UTC, enter the following command:

>config time timezone <delta_hrs>
The above commands are applicable to Cisco 2000, 2100, 4100, and 4400 Series Wireless LAN Controllers, Cisco Catalyst 6500 Series WiSM, Cisco Catalyst 3750 Series Integrated Wireless LAN Controllers, and the Wireless LAN Controller Module for Cisco Integrated Services Routers.

Wireless LAN Management

Cisco Wireless Control System

Starting with Release, the Cisco WCS fully supports DST. The customer must first specify the time zone the appliance is operating in; the start and end date and time of the DST is automatically enabled. The time zone is set by the operating system the WCS resides on.

Cisco Wireless Location Appliance

Starting with Release, the Cisco Wireless Location Appliance fully supports DST. The customer must first specify the time zone the appliance is operating in; the start and end date and time of the DST is automatically enabled. Use the following command to select the time zone:
[root@loc-server setup]# pwd
[root@loc-server setup]# ./

CiscoWorks Wireless LAN Solution Engine (WLSE) and WLSE Express

CiscoWorks WLSE and WLSE Express do not support DST. The CiscoWorks WLSE uses browser (client) time in most of its displays. The current CiscoWorks WLSE server time, in the local time zone, is displayed in the upper right corner of the screen.
In Internet Explorer, the timestamp usually consists of the browser time (hours:minutes:seconds) and date (14:17:16 10/12/2005, for example).
In some displays, the timestamp is the day of the week, month and day, browser time, timezone, and year (Sat Oct 12 11:15:01 PDT 2005, for example).
The CiscoWorks WLSE's internal system time is UTC; this is displayed in certain logs, such as the discovery run log.
To change the local time, please follow the following steps:

• Select Admin > Appliance > Time/NTP/Name/Web Timeout.

• In the Current Time area, select the new time and date parameters from the lists and click Update.

Service and Support

Cisco offers a wide range of services programs to accelerate customer success. These innovative programs are delivered through a unique combination of people, processes, tools, and partners, resulting in high levels of customer satisfaction. Cisco services help you to protect your network investment, optimize network operations, and prepare your network for new applications to extend network intelligence and the power of your business. For more information about Cisco services, see Cisco Technical Support Services or Cisco Advanced Services.

For More Information

For more information about Cisco wireless networking platforms, visit or contact your local account representative.