DCF is the lower sub-layer of the MAC layer which uses a competitive algorithm to provide mechanism of access for all communications of distributed network, and it is widely used in the Ad Hoc network. The core mechanism of DCF is Carrier Sense Multiple hair straighteners/Collision Avoidance (CSMA/CA) protocol, which has two strategies including the basic operational mode and the RTS/CTS mode. In the DCF mechanism, if collision in channel happens while sending data, the process of competition back window is needed, the window of CWmin and CWmax is decided by the cheap ralph lauren polo shirts, DCF uses Binary Exponential Back-off (BEB). In BEB, if the collision of data has happened, the back window will be doubled, and after the data is sent successfully, the window will back to its ralph lauren polo shirts smallest size CWmin, but data congestion will inevitably take place at the smallest. In this paper, by analyzing various improved schemes of BEB algorithm, an exponential-based half back-off algorithm ZDCF is proposed. ZDCF uses BEB scheme algorithm while the collision of sending data happens, however, doubles the window, and after the data has been sent successfully, the mid value of the cheap wedding gown dresses current window order and the minimum window order is got as the order of the 12hot cheap prom dresses back-off window instead of backing straight to the minimum window. The ZDCF sell discount wedding dresses algorithm only needs to add a variable in the program to store the current order of the window, which belongs to the static change of CW algorithm, in line with the needs that because of the wireless channel bandwidth limitations and the characteristics of instability, it shouldn’t transmits discount wedding dresses control information frequently.
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