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Teck Meng LIM Bu-Sung LEE Chai Kiat YEO
Researchers have proposed numerous approaches to providing Quality-of-Service (QoS) across the Internet. The IETF has proposed two reservation approaches: hop-by-hop bandwidth reservation (IntServ); and per-hop behaviour bandwidth reservation (DiffServ). An edge router generates traffic, accepts per-flow reservation and classifies them into predetermined service class; while a core router ensures different QoS guarantees for each service class. We propose an Edge-to-Edge Quality-of-Service Domain in which packet trains with the same service requirements aggregated using packet deadline at edge router. The properties of a packet train like Inter-Packet Departure Time, Inter-flow Departure Time and accumulated packet delay are embedded and used by our quantum-based scheduler and QoS packet forwarding scheme in core routers. Thus, we are able to extract per-queue and per-flow information. Each queue is reconstructed at core router with packets having an expected departure time that is relative to the ingress router. Useful functions like instantaneous service rate and fine granular dropping scheme can be derived with a combination of embedded information and relative virtual clock technique. The encapsulation of our packet train information converges mathematically. Through simulations, we show that our architecture can provide delay and rate guarantees and minimise jitter for QoS-sensitive flows that requires LR-coupled or LR-decoupled reservations.
The recent Internet needs a network structure and traffic engineering that can support various applications requiring differentiated traffic processing and a high quality of service. The extension of the Internet from wired to wireless systems that generate location-dependent and burst errors has made the support of good services more difficult with existing packet scheduling algorithms. Accordingly, this paper proposes a wireless differentiated service packet scheduling (WDSPS) algorithm that can provide reliable and fair services in differentiated wireless internet service networks. As such, the proposed scheduling algorithm solves the HOL blocking problem within a class packet queue that occurs in a wireless network, supports differentiated services for each class defined in a differentiated service network, and facilitates gradual and efficient service compensation not only among classes but also among flows within a class, thereby preventing a monopoly by one class or one flow. Simulations confirmed that the proposed WDSPS scheduling algorithm could provide the required QoS differentiation between classes and enhanced the service throughput under various wireless network conditions.
Abdulkhalig A. BILHAJ Kenichi MASE
This paper presents QoS control enhanced architecture for VoIP networks. In this architecture we use both the probe flow delay and average loss rate measurement systems. First we apply the probability-based EMBAC scheme on our delay system. Then we propose a new probability-based EMBAC with a severe congestion consideration scheme to improve the admission control scheme in both measurement systems. We compare the performance of the enhanced systems in terms of blocking probability under the same condition of achieving average packet loss rate no greater than the certain target by setting an appropriate admission threshold in each system under each scenario. In this study, it is shown through simulations that for the same target voice average loss rate, the enhanced systems proposed in this paper outperform the conventional schemes in handling the network resources. Then we will seek to prove that, for extra traffic loads within a busy period of time and with an optimal admission threshold chosen in advance, the enhanced systems can be a powerful and reliable EMBAC tool for VoIP networks in achieving high network performance with minimum blocking probability and minimum average loss rates. Finally it is shown that the enhanced systems have reasonable scalability.
Miguel FRANKLIN DE CASTRO Lela MERGHEM Dominique GAITI Abdallah M'HAMED
The new Internet has to provide the Quality of Services to converged multimedia services, in which each one may choose its own requirements. Managing such a dynamic network is not an easy task. A more intelligent and adaptive behavior is required from network management. We argue that agents are able to realize this task by dynamically adapting management mechanisms to the current network conditions. This article presents a Behavioral Multi-Agent-based model for QoS-enabled Internet. Based on this behavioral approach, we analyze network management mechanisms (or "elementary behaviors") in terms of performance and applicability profile. We use simulation to observe services performances when submitted to diverse QoS management elementary behaviors.
Sang-Jo YOO Yun-Ho KO Jae-Cheol KWON
This paper proposes a wireless scheduling algorithm that can provide the Internet with delay proportional differentiated services in wireless networks. When considering wireless network environments that include burst and location-dependent channel errors, the proposed WDPS (Wireless Delay Proportional Service) scheduling algorithm can adaptively serve packets in class queues based on the delivered delay performance for each class. The significant characteristics of the WDPS scheduler include support for a fair relative delay service, the provision of graceful throughput and delay compensations, and the avoidance of class queue-blocking problems. Simulations show that the proposed algorithm can achieve the desirable properties for providing delay proportional services in wireless networks.