Recently, Machine to Machine (M2M) and Internet of Things (IoT) technologies have been growing rapidly due to the development of tiny wireless devices. Industrial automation and Wireless Sensor Networks are the two most widely used applications of such technologies. However, existing technologies cannot accommodate the growing number of wireless devices. Therefore, the IEEE 802.11 Task group has proposed a new MAC enhancement feature in the IEEE 802.11ah.

 The RAW mechanism proposed in the IEEE 802.11ah restricts the uplink access to groups of STATION (STA)s to reduce the contention and collision among the STAs. Since the Restricted Access Window (RAW) mechanism can accommodate a large number of STAs, it can be suitable for M2M and IoT applications. However, restricting the STAs and allocating them into smaller groups will have a significant impact on their End-to-End delays. In this thesis work, we will evaluate the uplinkbased RAW mechanism for time-sensitive applications. To understand the impact of the RAW mechanism and its impact on the delay, the RAW mechanism is explained in terms of the impact of RAW slots and the impact of RAW groups.

 The Performance evaluation for the time-sensitive applications in IEEE 802.11ah has been carried out by using the developed simulator in Network Simulator -3(Ns-3). To evaluate the impact of the RAW slots and the RAW groups in the RAW mechanism, the Industrial automation and the Sensor Networks (IoT) use case scenarios from the IEEE 802.11ah task group have been used. The RAW mechanism restricts the channel access to the STAs by allocating the channel into slots and inside the RAW group there can be different RAW group parameters. Therefore, restricting them in terms of RAW slots and RAW groups will have an impact on delay. The new performance metrics has been proposed by considering the probability that the packet will meet the deadline based upon the End-to-End delay.