User Manual

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Understanding Industrial WLAN – IEEE 802.11
QoS for Video/Audio and Control
The dramatic growth of WLAN has also led to demands for video and audio transmission over WLAN. Quality
of Service (QoS) is therefore becoming an important topic for wireless communications. QoS is a network
term for controlling and measuring data transmission rates, throughputs and error rates. QoS is not of a big
concern for simple data transmission. However, it becomes more of an issue when it comes to audio and
especially video. Video requires high quality of flow and throughput control and lower error rates. All these are
In multimedia data transmission, it is important for delays arising from network latencies to be undetectable to
users.
IEEE 802.11e was set up to answer this call for QoS in WLAN. IEEE 802.11e is the amendment that defines
wireless LAN QoS enhancement in IEEE 802.11. WLAN QoS is achieved through modifications to the Media
Access Control (MAC) layer, solving the latency delay problem that is sensitive to multimedia and voice data
transmission.
Wireless Management
QoS is essential for wireless communication. It is an important element for wireless applications when it comes
to management. There are three layers of management, namely device management, network management,
and centralized management.
Device Management
When it comes to network management, device management is always the most basic task for all network
administrators. Often, wireless APs/Clients come with a management utility or web console that allows
network managers to locate and remotely configure the wireless APs/Clients.
Network Management
Above device management is the network
management layer. This layer requires a higher
level of software utilities to manage all wireless
nodes. The network management utility should
be able to perform multiplatform monitoring,
event management, alerting, real-time
performance monitoring, network discovery,
and topology mapping.
Centralized Management
More advanced network management tools
provide a complete solution for network
administrators including VPN, firewall, and
UTM. It also allows centralized management for
device maintenance.