The proposed analysis verifies that when RTS/CTS mechanism achieves lower packet delay,with respect to the basic access mechanism,it is of great importance to the rational use of RTS/CTS mechanism and the notable increase in the performance of IEEE 802.11 WLAN.
The limitations of the DCF(Distributed Coordination Function), a basic access mechanism of IEEE 802.11 Wireless LAN, in supporting Quality of Service(QoS) are discussed. EDCF (Enhanced DCF), a new access mechanism adopted by the future IEEE 802.11e standard for QoS support, is analyzed.
分析了现有 IEEE 802.11 无线局域网的基本接入机制 DCF(Distributed Coordination Function)对 QoS(Quality of Service)技术支持的局限性,介绍了未来具有 QoS 保证的 IEEE 802.11e 标准采用的一种新的 MAC 层接入机制 EDCF(Enhanced DCF)。
The origin mechanism of agricultural product quality security is a systematic engineering,which involves plantation and aquiculture of agricultural standardization,processing,standardized package,distribution,construction of information origin platform and construction of market access mechanism.
For this reason,we need to establish and improve the market access mechanism for urban land consolidation,perfect the market discipline,separate government administration from enterprise management,and follow the market economic principle of transparency,fairness,order,and competition,so as to realize social economic harmonious development in the urban land consolidation areas.
This paper analyzes on the demand of the information users and the features of the information service in the network times,and emphatically introduces the generation and development of the open access mechanism of the academic information exchange and its implementation methods in the network environment.
Beginning with the problems of solving the I/O bottleneck of high performance computer, this paper mainly analyzes the architecture, access mechanism, management mechanism and operating mechanism of PVFS, and provides an effective method for building high performance cluster file system.