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| Chapter 6 Wireless LAN |
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| TERM | DESCRIPTION |
| Roaming | If you have two or more NWAs (or other wireless access points) on your wireless |
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| network, you can enable this option so that wireless devices can change locations |
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| without having to log in again. This is useful for devices, such as notebooks, that |
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| move around a lot. |
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| Antenna | An antenna couples Radio Frequency (RF) signals onto air. A transmitter within a |
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| wireless device sends an RF signal to the antenna, which propagates the signal |
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| through the air. The antenna also operates in reverse by capturing RF signals from |
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| the air. |
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| Positioning the antennas properly increases the range and coverage area of a wireless |
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| LAN. |
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6.10.2 WMM QoS
WMM
WMM QoS prioritizes wireless traffic according to the delivery requirements of the individual and applications. WMM QoS is a part of the IEEE 802.11e QoS enhancement to certified
On APs without WMM QoS, all traffic streams are given the same access priority to the wireless network. If the introduction of another traffic stream creates a data transmission demand that exceeds the current network capacity, then the new traffic stream reduces the throughput of the other traffic streams.
The NWA uses WMM QoS to prioritize traffic streams according to the IEEE 802.1q or DSCP information in each packet’s header. The NWA automatically determines the priority to use for an individual traffic stream. This prevents reductions in data transmission for applications that are sensitive to latency and jitter (variations in delay).
6.10.2.1 WMM QoS Priorities
The following table describes the WMM QoS priority levels that the NWA uses.
Table 25 WMM QoS Priorities
Priority Level | description | |
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voice | Typically used for traffic that is especially sensitive to jitter. Use this priority to | |
(WMM_VOICE) | reduce latency for improved voice quality. | |
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video | Typically used for traffic which has some tolerance for jitter but needs to be | |
(WMM_VIDEO) | prioritized over other data traffic. | |
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best effort | Typically used for traffic from applications or devices that lack QoS capabilities. Use | |
(WMM_BESTEFFORT) | best effort priority for traffic that is less sensitive to latency, but is affected by long | |
delays, such as Internet surfing. | ||
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background | This is typically used for | |
(WMM_BACKGROUND) | that are allowed but that should not affect other applications and users. Use | |
background priority for applications that do not have strict latency and throughput | ||
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| requirements. | |
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| 85 |
NWA1000 Series User’s Guide | |
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