Abstract :
Next generation (NG) wireless networks are envisioned to provide high bandwidth to mobile users via bandwidth aggregation over heterogeneous wireless architectures. NG wireless networks, however, impose challenges due to their architectural heterogeneity in terms of different access schemes, resource allocation techniques as well as diverse quality of service requirements. These heterogeneities must be captured and handled dynamically as mobile terminals roam between different wireless architectures. However, to address these challenges, the existing proposals require either a significant modification in the network structure and in base stations or a completely new architecture, which lead to integration problems in terms of implementation costs, scalability and backward compatibility. Thus, the integration of the existing medium access schemes, e.g., CSMA, TDMA and CDMA, dictates an adaptive and seamless medium access control (MAC) layer that can achieve high network utilization and meet diverse quality of service (QoS) requirements. In this paper, an adaptive medium access control (A-MAC) layer is proposed to address the heterogeneities posed by the NG wireless networks. A-MAC introduces a two-layered MAC framework that accomplishes the adaptivity to both architectural heterogeneities and diverse QoS requirements. A novel virtual cube concept is introduced as a unified metric to model heterogeneous access schemes and capture their behavior. Based on the virtual cube concept, A-MAC provides architecture-independent decision and QoS based scheduling algorithms for efficient multi-network access. A-MAC performs seamless medium access to multiple networks without requiring any additional modifications in the existing network structures. It is shown via extensive simulations that A-MAC provides adaptivity to the heterogeneities in NG wireless networks and achieves high performance.
Keywords :
carrier sense multiple access; code division multiple access; mobile communication; quality of service; resource allocation; time division multiple access; A-MAC; adaptive medium access control; backward compatibility; bandwidth aggregation; carrier sense multiple access; code division multiple access; mobile terminals; multinetwork access; network utilization; next generation wireless terminals; quality of service; resource allocation; time division multiple access; virtual cube concept; Adaptive control; Bandwidth; Media Access Protocol; Multiaccess communication; Next generation networking; Programmable control; Proposals; Quality of service; Resource management; Wireless networks; Adaptive medium access control; heterogeneous QoS requirements; heterogeneous networks; next generation wireless networks; virtual cube concept;