Technical Reference; Wmm Qos; Spanning Tree Protocol (Stp); Rapid Stp - ZyXEL Communications NWA-1100 User Manual

Chapter 6 Wireless Settings Screen

6.5 Technical Reference

This section provides technical background information about the topics covered in
this chapter. Refer to
LAN.

6.5.1 WMM QoS

WMM (Wi-Fi MultiMedia) QoS (Quality of Service) ensures quality of service in
wireless networks. It controls WLAN transmission priority on packets to be
transmitted over the wireless network.
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 Wi-Fi wireless networks.
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 ZyXEL Device uses WMM QoS to prioritize traffic streams according to the
IEEE 802.1q or DSCP information in each packet's header. The ZyXEL Device
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).

6.5.2 Spanning Tree Protocol (STP)

STP detects and breaks network loops and provides backup links between
switches, bridges or routers. It allows a bridge to interact with other STP-
compliant bridges in your network to ensure that only one route exists between
any two stations on the network.

6.5.2.1 Rapid STP

The ZyXEL Device uses IEEE 802.1w RSTP (Rapid Spanning Tree Protocol) that
allow faster convergence of the spanning tree (while also being backwards
compatible with STP-only aware bridges). Using RSTP topology change
information does not have to propagate to the root bridge and unwanted learned
addresses are flushed from the filtering database. In RSTP, the port states are
Discarding, Learning, and Forwarding.
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Appendix E on page 157 for further readings on Wireless
ZyXEL NWA-1100 User's Guide