The current Internet can only provide the best-effort services. By growing the Internet and its applications, new services with different requirements are developed. The differentiated Services (Diffserv) [1-3] is a scalable model for providing end-to-end quality of services. A Diffserv router consists of different components including classifier, meter, marker, dropper, shaper and scheduler. In this paper, we use the benefits of the fuzzy logic controller to design a fuzzy based traffic conditioner for Internet differentiated services. Our proposed model consists of three major parts: a Fuzzy Meter/Marker (FM), a Fuzzy Active Queue Management (FAQM) algorithm and a Fuzzy Scheduler (FS). The proposed FM used to measure and mark the input traffic is based on the single rate Three Colors Meter (srTCM) mechanism [4]. The FM meters an IP packet stream and marks its packets green, yellow, or red. The proposed FAQM is a fuzzy implementation of the well-known BLUE Active Queue Management (AQM) algorithm [5]. To achieve a good throughput and reasonable packet loss ratio, the proposed FAQM mechanism employs a fuzzy logic controller. The third part of the proposed fuzzy traffic conditioner is FS. It is based on the traditional Weighted Fair Queue (WFQ) mechanism [6] that tunes the weight of each queue by a fuzzy logic controller. To evaluate the performance of the proposed model, we developed a software in C++ environment to simulate it. Different network topologies with different traffic parameters were performed. The simulation results easily helped us to judge the merit of the proposed FM, FAQM and FS because of their remarkable performance over the traditional non-fuzzy mechanisms.

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