ZyXEL Communications NBG-416N User Manual

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Appendix D Wireless LANs
NBG-416N User’s Guide
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Figure 134   
Basic Service Set
ESS
An Extended Service Set (ESS) consists of a series of overlapping BSSs, each containing an access 
point, with each access point connected together by a wired network. This wired connection 
between APs is called a Distribution System (DS).
This type of wireless LAN topology is called an Infrastructure WLAN. The Access Points not only 
provide communication with the wired network but also mediate wireless network traffic in the 
immediate neighborhood. 
An ESSID (ESS IDentification) uniquely identifies each ESS. All access points and their associated 
wireless clients within the same ESS must have the same ESSID in order to communicate.