In this paper, the authors deal with IEEE 802.15.4 beacon enabled and non beacon enabled multi-hop star wireless sensor networks with varying traffic loads. For high channel utilization and low power consumption, impact of MAC parameters such as Beacon Order (BO) and Superframe Order (SO) has been analyzed. IEEE 802.1.5.4 MAC works in two modes, beacon and non beacon mode. This paper provides the performance analysis of IEEE 802.15.4 star topology using DYMO protocol by dynamically adjusting the BO and SO values depending on the traffic loads. Various network performance parameters calculated are throughput, average end to end delay, average jitter, total energy consumption, percentage of time in sleep mode, residual battery consumption.