This paper examines the overhead associated with the IEEE Std 802.15.3 medium access control (MAC) protocol when used in conjunction with Ultra Wide-Band (UWB) radio technology. Particular features of the protocol examined include establishing, modifying and terminating data streams. The main focus of the paper is to investigate the overhead introduced in terms of energy consumption to manage the communication links. One of the main UWB technology candidates, Impulse-Radio (IR-UWB), utilizes very short time domain pulses which are low power and difficult to detect. This raises the question of how to design an efficient MAC protocol to harness the potential of the physical layer (PHY). For high data rate WPAN applications, the IEEE Std 802.15.3 protocol has been proposed as a suitable MAC. In the simulations the data source rate and the number of devices in the network are varied and the considerable overhead produced by command frames is observed.