Linksys WCG200 User Guide - Page 36

Wireless-G Cable Gateway Advanced Wireless Settings Tab On this screen you can access the Advanced Wireless features, including Basic Data Rates, Control Tx Rates, Beacon Interval, DTIM Interval, Fragmentation Threshold, RTS Threshold, and Authentication Type. • Basic Data Rates. Select Min or All from the drop-down menu for rate. • Control Tx Rates. Select Min or All from the drop-down menu for the transmission rate. All will negotiate the best possible connection speed between the Gateway and a wireless client. • Beacon Interval. The default value is 100. Enter a value between 1 and 65,535 milliseconds. The Beacon Interval value indicates the frequency interval of the beacon. A beacon is a packet broadcast by the Gateway to synchronize the wireless network. • DTIM Interval. The default value is 3. This value, between 1 and 255 milliseconds, indicates the interval of the Delivery Traffic Indication Message (DTIM). A DTIM field is a countdown field informing clients of the next window for listening to broadcast and multicast messages. When the Gateway has buffered broadcast or multicast messages for associated clients, it sends the next DTIM with a DTIM Interval value. Its clients hear the beacons and awaken to receive the broadcast and multicast messages. • Fragmentation Threshold. This value should remain at its default setting of 2346. The range is 256-2346 bytes. It specifies the maximum size for a packet before data is fragmented into multiple packets. If you experience a high packet error rate, you may slightly decrease the Fragmentation Threshold. Setting the Fragmentation Threshold too low may result in poor network performance. Only minor modifications of this value are recommended. • RTS Threshold. This value should remain at its default setting of 2347. The range is 0-2347 bytes. Should you encounter inconsistent data flow, only minor modifications are recommended. If a network packet is smaller than the preset RTS threshold size, the RTS/CTS mechanism will not be enabled. The Gateway sends Request to Send (RTS) frames to a particular receiving station and negotiates the sending of a data frame. After receiving an RTS, the wireless station responds with a Clear to Send (CTS) frame to acknowledge the right to begin transmission. • Authentication Type. The default is set to Open System or Shared Key, which allows either Open System or Shared Key authentication to be used. For Open System authentication, the sender and the recipient do NOT use a WEP key for authentication. For Shared Key authentication, the sender and recipient use a WEP key for authentication. If you want to use only Shared Key authentication, then select Shared Key. In most cases, you should keep the default, Open System or Shared Key. When finished making your changes on this tab, click the Save Settings button to save these changes, or click the Cancel Changes button to undo your changes. Figure 5-16: Advanced Wireless Settings packet: a unit of data sent over a network. beacon internal: data transmitted on your wireless network that keeps the network synchronized. dtim (delivery traffic indication message): a message included in data packets that can increase wireless efficiency. fragmentation: breaking a packet into smaller units when transmitting over a network. rts (request to send): a networking method of coordinating large packets through the RTS Threshold setting. Chapter 5: Configuring the Wireless-G Cable Gateway 30 The Wireless Tab