Extreme Networks Altitude 4700 Series, Руководство по продукции

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Network Management
Altitude 4700 Series Access Point Product Reference Guide
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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 MU 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 MU activate the new U-APSD power save
approach when a VoIP traffic stream is detected. The MU 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 MU 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 802.11 security 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.
NOTE
Beginning with this most recent 4.1 release of the Access Point firmware, users now have the ability to
customize the appearance of an Access Point’s hotspot pages. The Access Point’s hotspot feature is supported by
three customer accessible pages (login page, welcome page and failure page) displayed on the client attempting to
access the AP’s supported hotspot. These three pages can be unique to each hotspot supported by one of the
Access Point’s 16 WLANs. For more information, see
“Customizing a Hotspot Display” on page 165 .
The Access Point hotspot functionality requires the following:
●
HTTP Redirection —Redirects unauthenticated users to a specific page specified by the Hotspot
provider.
●
User authentication— Authenticates users using a RADIUS server.
●
Walled garden support —Enables a list of IP address (not domain names) accessed without
authentication.
●
Billing system integration —Sends accounting records to a RADIUS accounting server.