Frequently Asked Questions Q: What do the Advanced Wireless settings do?A: Beacon Interval (also known as TIM)
The Beacon Interval specifies the duration between beacon packets. Access Points broadcast Beacons or Traffic Indication Messages (TIM) in order to synchronize wireless networks. The default setting of 100 should be ideal for most situations. In a "noisy" environment - one with much interference - decreasing the Beacon Interval may improve network performance. In very remote locations (with few wireless nodes) this value may be increased.
The RTS (Request to Send) Threshold is the amount of time a wireless device, attempting to send, will wait for a recipient to acknowledge that it is ready. To ensure communication, the maximum value should be used. Decreasing this value causes the sending device to discard the current packet and move on to the next.
Assume that node A wants to send a frame to node B. Node A initiates the process by sending an RTS frame. The RTS frame has the following purposes:
If node B receives the RTS, it responds with CTS (Clear to Send). The CTS also silences stations in the vicinity.
This value specifies the maximum size of a packet before the data is fragmented into two or more packets. This value should be set to the maximum in most situations. Reducing this value in a clear environment will decrease throughput.
However, the Fragmentation Threshold value may be decreased in noisy environments to ensure data transmission. For example, because of the burst impulsive characteristic of microwave interference, reducing the packet size can increase communication performance.
This setting determines how often the Access Point's Beacon (TIM) contains a delivery traffic indication message (DTIM). The DTIM tells client devices in power-save mode that a packet is waiting for them. The default setting causes client devices using power-save mode to wake up. To conserve battery power in client devices using power-save mode, increase the Data Beacon Rate (DTIM) setting. However, setting the DTIM too high may cause a wireless client to lose its network connection.
The DTIM is a multiple of the Beacon (TIM). So if the DTIM was set to 3, a DTIM message would be sent with every third Beacon.
Most Access Points and client adapters have a setting called Preamble Type - Short or Long. If all Clients and Access Points in your wireless network support Short Preamble, then enabling it can boost overall throughput. However, if any wireless device does not support Short Preamble, then it will not be able to communicate with your network.
If you are not sure whether your radio supports the Short RF preamble, then make sure you disable this feature. Long Preamble is the default, as it is a required setting for Wi-Fi compatibility.