ZyXEL Communications wireless n gigbit router zyxel User Manual

 Chapter 7 Wireless LAN

NBG-460N User’s Guide

The following requirements must be met in order for wireless stations to roam 
between the coverage areas. 

All the access points must be on the same subnet and configured with the same 
ESSID. 

If IEEE 802.1x user authentication is enabled and to be done locally on the access 
point, the new access point must have the user profile for the wireless station.

The adjacent access points should use different radio channels when their 
coverage areas overlap. 

All access points must use the same port number to relay roaming information. 

The access points must be connected to the Ethernet and be able to get IP 
addresses from a DHCP server if using dynamic IP address assignment. 

This section discusses the Quality of Service (QoS) features available on the NBG-
460N.

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 delivery requirements. 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 NBG-460N uses WMM QoS to prioritize traffic streams according to the IEEE 
802.1q tag or DSCP information in each packet’s header. The NBG-460N 
automatically determines the priority to use for an individual traffic stream. This 
prevents reductions in data transmission for applications that are sensitive to 
latency (delay) and jitter (variations in delay).