User guide

The Controller, Access Points and Convergence Software solution
A31003-W1010-A100-1-7619, July 2005
22 HiPath Wireless Controller, Access Points and Convergence Software V3.0: User Guide
HWC_Intro.fm
Controller, Access Points and Convergence Software and your network
The HiPath Wireless Controller stores the wireless device’s current session information, such
as IP address and MAC address. If the wireless device has not disassociated, then when it
requests network access on a different Wireless AP, the HiPath Wireless Controller can match
its session information and recognize it as still in a current session.
In addition, a HiPath Wireless Controller can learn about other HiPath Wireless Controllers on
the network, and then exchange client session information. This enables a wireless device user
to roam seamlessly between different Wireless APs on different HiPath Wireless Controllers.
2.2.8 Availability
Controller, Access Points and Convergence Software provides seamless availability against
Wireless AP outages, HiPath Wireless Controller outages, and even network outages.
For example, if one Wireless AP fails, coverage for the wireless device is automatically provided
by the next nearest Wireless AP.
If a HiPath Wireless Controller fails, all of its associated Wireless APs, or access points, can
automatically migrate to another HiPath Wireless Controller that has been defined as the
secondary or backup HiPath Wireless Controller. When the original HiPath Wireless Controller
returns to the network, the Wireless APs automatically re-establish their normal connection
with their original HiPath Wireless Controller.
2.2.9 Quality of Service (QoS)
Controller, Access Points and Convergence Software provides advanced Quality of Service
(QoS) management, in order to provide better network traffic flow. Such techniques include:
● WMM (Wi-Fi Multimedia): enabled globally on the Wireless AP. For devices with WMM
enabled, the standard provides multimedia enhancements for audio, video, and voice
applications. WMM shortens the time between transmitting packets for higher priority
traffic. WMM is part of the 802.11e standard for QoS.
● IP ToS (Type of Service) or DSCP (Diffserv Codepoint): the ToS/DSCP field in the IP
header of a frame is used to indicate the priority and Quality of Service for each frame. The
IP TOS and/or DSCP is maintained within CTP (CAPWAP Tunneling Protocol) by copying
the user IP QoS information to the CTP header — this is referred to as Adaptive QoS.
Quality of Service (QoS) management is also provided by:
● assigning high priority to an SSID (configurable)
● Adaptive QoS (automatic)
● support for legacy devices that use SpectraLink Voice Protocol (SVP) for prioritizing voice
traffic (configurable)