—The growth of the Internet in the last years has been pushed by increasing requirements in terms of capacity, security and reliability. Moreover, improvements in multimedia applications need mechanisms and architectures to accomplish Quality of Service(QoS) and differentiated services. Technology development has shown that the evolution of processing power cannot cope with the link capacity growth. Therefore a link capacity scheduler is no longer sufficient to assure efficient service differentiation to end-users, but a proper computing power allocation for packet processing must be adopted. In this paper a processing scheduling scheme for Intel® IXP2XXX Network Processors is proposed. A model of the architecture is defined and an ad-hoc simulator is developed to help the comprehension of the system and the re-design of the application. Finally experimental results show the performance of the proposed algorithm.