In this paper, waiting time analysis for the delay sensitive traffic especially in Internet of things (IoT) is performed. The analysis is based on probabilistic prediction approach for providing Quality of Service (QoS). A dynamic packet scheduling scheme is considered to provide service differentiation and preferential treatment to delay sensitive traffic. The scheduler focuses on reducing the waiting time of high priority delay sensitive services in the queue and simultaneously keeping medium and low priority services within tolerable limits. The scheme uses the difference in probability of average queue length of high priority packets at previous cycle and current cycle to determine the probability of average weight required in the current cycle. This offers optimized bandwidth allocation to all the services. The performance of the algorithm is investigated using MPEG-4 traffic traces under different system loadings. The results show the improved performance with respect to waiting time for scheduling high priority packets.