ZyAIR B-2000 Wireless LAN Gateway with 4-Port Switch

ESS ID

Extended Service Set (ESS) is defined as one or more access points (APs) acting as a bridge between a wired LAN and the associated wireless clients. The ESS ID is a unique ID given to the APs and the wireless clients that participate in the same wireless network. You can think the EES ID as being similar to a workgroup name in a Microsoft network.

Wireless LANs can be as simple as two computers with wireless network interface cards (NICs) communicating in a peer-to-peer network or as complex as a number of computers with wireless NICs communicating through access points which bridge network traffic to the wired LAN.

The ESS ID provides minimum security for your network, see section on Wireless Security Setup for more information.

RTS Threshold

The RTS (Request To Send) Threshold prevents the hidden node problem. Hidden node problem occurs when two stations are within the range of the same access point, but are not within the range of each other. The following figure illustrates the hidden node problem. Both stations (STA) are within the range of the AP, however, they cannot hear each other. Therefore, they are considered as hidden nodes from each other. When a station starts data transmission with the access point, it might not know that the other station is already using the wireless medium. When these two stations send data at the same time, they might collide when arriving simultaneously at the AP. The collision will most certainly result in a loss of messages for both stations.

Figure 3-8 RTS Threshold

Thus, RTS Threshold mechanism provides a solution to prevent data collisions. When you enable RTS Threshold on a possible hidden station, this station and its AP will use a Request to Send/Clear to Send protocol (RTS/CTS). The station will send an RTS message to the AP, informing that it is going to transmit the data. Upon receipt, the Access Point will respond with a CTS message to all stations within its range to

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