Avaliação experimental do protocolo RT-WiFi em ambientes abertos

Networks known as WiFi (IEEE 802.11 standard) are widely used in applications ranging from simple home environments systems to complex control systems network. However, the extensions incorporated into the standard to provide Quality of Service (QoS) are still unable to guarantee time constraints for real-time (RT) communications requirements. This paper presents an experimental validation of the RT-WiFi protocol that was recently proposed and analyzed through simulation. The experimental results demonstrate the feasibility of implementing the RT-WiFi protocol and improving the QoS level of communications through a comparative analysis with the EDCA mechanism, which is a mechanism incorporated in the IEEE 802.11 standard to provide different levels of transmission priority of different types of traffic.

Performance Analysis on IEEE 802.11ah Standard with Enhanced Distributed Channel Access Mechanism

IEEE 802.11ah is a new task group on the IEEE 802.11 standard designed to work on the 900 MHz. It is with a range of communication coverage up to 1kilometer, lower energy consumption, and up to 8191 stations. There are two types of STAs in 802.11ah: sensor type to support sensor service and non-sensor type for offload service. In this research, it only focuses on non-sensor STA. For non-sensor STA, maximizing throughput is more important than power consumption. This research aims to see the performance of IEEE 802.1 1ah with Enhanced Distributed Channel Access (EDCA). To achieve that purpose, a mechanism is needed to provide guarantees various services required by theSTA. EDCA is an access mechanism used to set the Quality of Service (QoS) for the IEEE 802.11 standard through modifications in MAC layer. In this research,it focuses on one of the EDCA parameters, Arbitration Inter-Frame Space (AIFS). In addition, this research also focuses on the 802.11ah feature is Restricted Access Window (RAW) by changing the number of the RAW groups. From the results of the research, it is found that the improvement scheme with Arbitration Inter-Frame Space Number (AIFSN) value AC BK = 2, AC BE = 1, AC VI = 1, AC VO = 1 has better performance compared to the default scheme with AIFSN value AC BK = 7, AC BE = 3, AC VI = 2, AC VO = 2) with an average throughput of 1.504598 Mbps, average overall delay of 0.066242 second and average PDR of 62%. In addition, changes in the number of RAW groups and RAW slots affect network performance. This feature can improve the value of throughput, average delay, and Packet Delivery Ratio. The goals of this research is to know the effect of AIFSN value changes on AIFSN parameters, variation of RAW group and RAW slot number to throughput,average delay and packet delivery ratio.

Analisis Performansi Perubahan RAW Slot Pada Standar IEEE 802.11ah

The increasing needs and demands of diverse services by the users to be able to exchange and obtain information in real time, reliable, and flexible to be one of the problems faced by existing communication technology. WLAN on the IEEE 802.11 standard is one of the wireless technologies that can be the solution of the problem. It has a relatively small area of ??communication that is between 20-70 meters only, only able to serve up to 2007 stations, and has considerable energy consumption, causing some systems contained in the WLAN in IEEE 802.11 standard less work maximally. With these shortcomings, the WLAN on the IEEE 802.11 standard introduces a new task group called IEEE 802.11ah. IEEE 802.11ah is a new WLAN standard working on the 900 MHz frequency spectrum, a 1 kilometer communications coverage area, capable of serving 8192 stations with new AID hierarchies, has lower energy consumption and can increase throughput value by RAW mechanism. This study will make changes to the number of RAW slots in the IEEE 802.11ah to see how they affect the network performance. In this research it is found that the change of RAW slot number influence to network performance, in this case is throughput, average delay, packet delivery ratio and energy consumption.