The transport and diffusion properties for the velocity of a Fermi-Ulam model were characterized using the decay rate of the survival probability. The system consists of an ensemble of non interacting particles confined to move along and experience elastic collisions with two infinitely heavy walls. One is fixed, working as a returning mechanism of the colliding particles while the other one moves periodically in time. The diffusion equation is solved and the diffusion coefficient is numerically estimated by means of the averaged square velocity. Our results show remarkably good agreement of the theory and simulation for the chaotic sea below the first elliptic island in the phase space. From the decay rates of the survival probability, we obtained transport properties that can be extended to other nonlinear mappings, as well to billiard problems. We study the dynamics of an ensemble of non interacting particles moving constrained by two infinitely heavy walls, where one of then is moving periodically in time and the other is fixed. This problem, also known as Fermi-Ulam model, has application in many areas, including astrophysics, atom-optics, quantum mechanics, among others. The diffusive behaviour of the velocity, here set as the way the transport of orbits occurs in the phase space, is investigated considering transport properties obtained from the decay rate of the survival probability, defined by means of escape formalism. Since the system present mixed dynamics, stickiness phenomenon may influence the transport causing anomalous diffusion. In this study we developed an analytical approach for the diffusion coefficient along the transport through the chaotic sea considering escape rate formalism and survival probability analysis. The numerical results we obtained are in good agreement with the theory, and confirm the robustness of the formalism. The results obtained here can be extended to other similar dynamical systems.