TRENDnet TEW-740APBO Users Guide - Page 66

TRENDnet User's Guide TEW-740APBO  TxStream/Rx Stream: Select the amount of transmit (TX) and Receive (RX) streams. By default, it's 2.  Channel Bandwidth: The "20/40" MHz option is usually best. The other option is available for special circumstances.  Extensions Channel: Select which section of channels to use for extension channels.  MCS: This parameter represents transmission rate. By default (Auto) the fastest possible transmission rate will be selected. You have the option of selecting the speed if necessary. (Refer to Appendix C. MCS Data Rate) Wireless Advanced Setup To achieve optimal wireless performance, it is necessary to tweak advance setting per requirements properly, not necessary higher the better or lower. The administrator can change the RTS threshold and fragmentation threshold settings for the system. Please click on Wireless -> Advanced Setup and follow the below setting. © Copyright 2016 TRENDnet. All Rights Reserved.  Short Slot : By default, it's "Enable" for reducing the slot time from the standard 20 microseconds to the 9 microsecond short slot time. Slot time is the amount of time a device waits after a collision before retransmitting a packet. Reducing the slot time decreases the overall back-off, which increases throughput. Back-off, which is a multiple of the slot time, is the random length of time a station waits before sending a packet on the LAN. For a sender and receiver own right of the channel the shorter slot time help manage shorter wait time to re-transmit from collision because of hidden wireless clients or other causes. When collision sources can be removed sooner and other senders attempting to send are listening the channel(CSMA/CA) the owner of the channel should continue ownership and finish their transmission and release the channel. Then, following ownership of the channel will be sooner for the new pair due to shorter slot time. However, when long duration of existing collision sources and shorter slot time exist the owners might experience subsequent collisions. When adjustment to longer slot time can't improve performance then RTS/CTS could supplement and help improve performance.  ACK Timeout: ACK timeout is in the range of 1~255 and set in unit of microsecond. The default value is 32 microsecond. All data transmission in 802.11b/g request an "Acknowledgement" (ACK) send by receiving radio. The transmitter will resend the original packet if correspondent ACK failed to arrive within specific time interval, also refer to as "ACK Timeout". ACK Timeout is adjustable due to the fact that distance between two radio links may vary in different deployment. ACK Timeout makes significant influence in 66