"This paper addresses the stabilization problem of delay models of Transmission Control Protocol/Active Queue Management (TCP/AQM) by using a Proportional- Derivative (PD) controller as AQM strategy. The complete set of PD controllers that exponentially stabilizes the linearization is determined in counterpart with the existing works in the literature which only give an estimate of it. Additionally, a simple procedure for determining a non-fragile PD controller that admits controller coefficient perturbations is provided."