Modern Third Generation Wireless Networks demand more and more resources in order to satisfy customers� needs. And these resources can only be provided by a good Power Control. However, power control needs an algorithm in order to work at the margin of the Quality of Service (QoS) requirements. This work is related to this; we propose a power control algorithm modeled under probabilistic criteria. This means, applying a Markovian model to a MAC Protocol (power control algorithm), in order to optimize the power assigment to each user in the system. This protocol is highly interrelated to the power control functionality in order to extract the maximum capacity and flexibility out of the WCDMA scheme. Once it is done, the algorithm is submitted to different scenarios to demonstrate its capabilities and limitations, also thus analyze its behavior under different conditions and viewpoints. At the end, conclusions are listed, together with future work and proposals to strengthen this work.