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As wireless networks evolves towards the 3G and 4G architectures the mobile core networks provides a platform for all-IP convergence of mobile and fixed networks allowing for better integration of the Internet and cellular networks, providing better quality of service, charging mechanisms and integration of different services. Due to this convergence, there have been various evidences of interoperability limitations between the mobile and fixed networks such as protocol adaptation, end-to-end Quality of Service (QoS), charging and signalling interworking. Most of these limitations are currently been addressed by respective standards bodies and various proposals are being implemented. In this paper we investigate the signalling limitations across converged networks which are caused by the use of different Session Initiation Protocol (SIP) profiles for signalling in both mobile and fixed networks. We carried out various performance based simulations on the 3GPP proposed solution in which our results reveal critical shortcomings in the solution. We then proposed a new configuration for the system to enable the solution work more efficiently. [ABSTRACT FROM AUTHOR]

Ad hoc networking will become a major technology for wireless connectivity beside the multimedia necessity within the next few years. There are too many applications where one-to-many dissemination is necessary. Most of these applications are characterized by the close collaboration teams with requirements for audio, video conferencing and data sharing which QoS parameters such as bandwidth and delay are very critical for them. In this paper, an efficient algorithm named is proposed to improve the route discovery mechanism in MAODV for QoS multicast routes. QoS-MAODV especially can establish a multicast tree with the minimum required bandwidth support and decrease the end-to-end delay between each destination and the source node. It can establish QoS routes with the reserved bandwidth on per chosen flow. To perform accurate resource reservation, we have developed a method for estimating the consumed bandwidth inmulticast trees by extending the methods proposed for unicast routing. The simulation results show that QoS-MAODV protocol produces higher throughput and lower delay in comparison with MAODV protocol. [ABSTRACT FROM AUTHOR]

This paper presents a novel network design algorithm for Wireless Local Area Networks (WLANs) considering optimal access point placement and frequency channel assignment problems. The proposed algorithm is a cross-layer approach, accounting the physical layer and the data link layer functionalities of the WLANs in the network design process. Specifically, a multi-objective optimization problem is defined. The proposed objective function separates the physical layer considerations and the data link layer contributions in order to differently change the weights of the two characteristics of WLANs. Numerical results are presented and the jointed impact of the physical and the data link layer functionalities on the WLAN quality of services are evaluated. [ABSTRACT FROM AUTHOR]