Reconfigurable optical add/drop multiplexers (ROADMs) can be classified into three categories according to their underlying switching technologies: Category I consists of a single large optical switch; category II is composed of a number of small optical switches aligned in parallel; and category III has a single optical switch and only one wavelength being added/dropped. The ROADM wavelength occupancy probability is not same when implemented in dynamic optical networks. In this paper, to evaluate the wavelength-routing capability of ROADMs of category I in dynamic optical networks, we design Bernoulli, Poisson and Pascal models for smooth, regular and peak types of traffic. Through Analytical and Simulation results, we have determined the routing power of cat-I of ROADM networks for all traffic models.