Nima Nafisi

Learn More
Context-aware computing can play a major role to improve the services of mobile networking systems. In this paper, we focus on optimizing handover decisions based not only on the signal quality, but also on the knowledge about the context of mobile devices and networks. Since context information and context processing evolves fast, we propose a flexible,(More)
In order to provide end-to-end QoS in B3G systems, based on the UMTS architecture, the DiffServ framework can be used in the data plane of the IP core network of the mobile access network. Among the different schemes proposed for the control plane of DiffServ, the Internet2 bandwidth broker approach has been chosen for its centralized management nature,(More)
The next generation mobile system is expected to support the continuous increase of users requirements. Through the high flow rates of these networks, new applications constraints are more complex and may be change dynamically and rapidly for wireless systems. The service heterogeneity provided by these applications has a great influence on system(More)
Beyond 3G wireless networks must be able to coordinate services within a diverse network environment. One of the most challenging problems for coordination is vertical handover (VHO), which is the decision for a mobile node to change the point of attachment between different types of networks. While traditional handover is based on received signal strength(More)
This paper describes the motivation, methodology and implementation approach of the testbed that has been developed in the framework of the EVEREST project. Such testbed is used for demonstrating some of the main concepts addressed within the project, concerning both: common radio resource management strategies and end-to-end QoS architectures and(More)
This paper develops a feasible architecture for end-to-end QoS management over B3G networks where multiple heterogeneous radio access networks (RAN) can be coordinated at radio level by means of supporting Common Radio Resource Management (CRRM) functionalities. The presented approach is claimed to be innovative as long as it is inspired in the most(More)
In this paper, the design issues of a coverage-based CRRM strategy are studied to support voice services in a heterogeneous UMTS/GSM environment which distribute the traffic load by controlling the effective UMTS coverage through a predefined pathloss threshold. Comparing with the conventional Load Balancing strategy, the proposed coverage-based CRRM gives(More)
In this paper, we proposed a coverage-based common radio resource management (CRRM) strategy to improve the system performance for a heterogeneous CDMA/TDMA cellular system. In this strategy, with full coverage guaranteed by FDMA/TDMA systems, our theoretical numerical results show that the proposed coverage-based CRRM has the potential to improve the(More)
A link adaptation schemes is proposed to improve the efficiency to support DiffServ traffic over CDMA air interface. To differentiate the resource allocation between DiffServ PHBs and between the in/out profile packets within each AF class, two-level differentiation is done in the proposed scheme: inter-class differentiation and infra-class differentiation.(More)