Brocade Mobility 5181 Access Point Product Reference Guide (Supporting software release 4.4.0.0) - Manual (Page 128)

114 Brocade Mobility 5181 Access Point Product Reference Guide
53-1002516-01
Enabling wireless LANs (WLANs)
5
9. Click Apply to save any changes to the New QoS Policy or Edit QoS Policy screen to return to the
Quality of Service Configuration screen. Navigating away from the screen without clicking Apply
results in all changes to the screens being lost.
10. Click Cancel to securely exit the New QoS Policy or Edit QoS Policy screen and return to the
Quality of Service Configuration screen.
11. Click Logout within the Quality of Service Configuration screen to securely exit the Access Point
applet. A prompt displays confirming the logout before the applet is closed.
U-APSD (WMM Power Save) support
The access point now supports Unscheduled Automatic Power Save Delivery (U-APSD), often
referred to as WMM Power Save. U-APSD provides a periodic frame exchange between a voice
capable Client and the access point during a VoIP call, while legacy power management is still
utilized for typical data frame exchanges. The access point and its associated Client activate the
new U-APSD power save approach when a VoIP traffic stream is detected. The Client then buffers
frames from the voice traffic stream and sends a VoIP frame with an implicit "poll" request to its
associated access point. The access point responds to the poll request with buffered VoIP stream
frame(s). When a voice-enabled Client wakes up at a designated VoIP frame interval, it sends a
VoIP frame with an implicit "poll" request to its associated access point. The access point responds
to the poll request with buffered VoIP stream frame(s).
NOTE
The access point ships with the U-APSD feature disabled by default. It is automatically enabled when
WMM is enabled for a WLAN. Thus, U-APSD is only functional when WMM is enabled. If WMM is
disabled, then U-APSD is disabled as well.
Configuring WLAN hotspot support
The access point enables hotspot operators to provide user authentication and accounting without
a special client application. The access point uses a traditional Internet browser as a secure
authentication device. Rather than rely on built-in 802.11security features to control access point
association privileges, configure a WLAN with no WEP (an open network). The access point issues
an IP address to the user using a DHCP server, authenticates the user and grants the user to
access the Internet.
When a user visits a public hotspot and wants to browse to a Web page, they boot up their laptop
and associate with the local Wi-Fi network by entering the correct SSID. They then start a browser.
The hotspot access controller forces this un-authenticated user to a Welcome page from the
hotspot Operator that allows the user to login with a username and password.
The access point hotspot functionality requires the following:
• HTTP Redirection - Redirects unauthenticated users to a specific page specified by the Hotspot
provider.
TXOPs Time 32usec The TXOPs Time is the interval the transmitting Client is assigned for
transmitting. The default for Background traffic is 0. The same TXOPs
values should be used for either the 802.11a or 802.11b/g radio, there is
no difference.
TXOPs Time ms TXOP times range from 0.2 ms (background priority) to 3 ms (video priority)
in a 802.11a network, and from 1.2 ms to 6 ms in an 802.11b/g network.
The TXOP bursting capability greatly enhances the efficiency for high data
rate traffic such as streaming video