In this paper, we present an evaluation of the impact of several protocol parameters of the ISO 18000-6 Type-C protocol, also known as EPC Class-1 Generation-2 RFID protocol, on the performance of the RFID system. Specifically, we evaluate Tari, operating frequency, pulse width, and modulation index protocol parameters while utilizing a constant transmitted power. The experiments were designed to eliminate the effects of the tag's antenna design. All experiments were conducted in an anechoic chamber. The study shows that utilizing the slowest Tari with half duty cycle and the highest modulation index allows the reader to receive the maximum power from the tag resulting in longer reading distances. The fastest Tari with half duty cycle and highest modulation index has the fastest read rate. The tags respond with the Tari as small as 5 musec which provides a 5% read rate increase compared to the fastest Tari specified in the protocol.