Wireless/Redundant Edge Services xl Module Management and Configuration Guide WS.02.xx and greater

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Introduction
Radio Ports
A wireless station must send all traffic to it RP. However, the RP can then
forward the traffic to another station in the BSS. For tighter security, you can
block these inter-station communications entirely, or you can force them to
pass through the Wireless Edge Services xl Module, where ACLs can be
applied. See “Controlling Inter-Station Traffic” on page 4-63 of Chapter 4:
Wireless Local Area Networks (WLANs).
Figure 1-19. Infrastructure Mode
BSSID
The BSSID is the RP’s MAC address in a BSS. (See Figure 1-18.) Wireless
stations in a BSS address all frames to the BSSID.
ESS
An ESS is a set of BSSs that share a common network name, or SSID. An ESS
may consist of many RPs, and on the Physical Layer each of these RPs manages
a different shared medium. However, logically all of the RPs and the stations
they support are part of the same network, identified by the same SSID. The
WLAN configured with this SSID defines all options for the ESS.
In contemporary networks, it is often more useful to talk about an ESS than
a BSS because users may roam from RP to RP. Each RP may support a different
BSS, but all share the same SSID, as shown in Figure 1-20. In fact, at the logical
layer, all BSSs in an ESS appear as the same BSS to a wireless station.