More and more users subscribing to wireless broadband services are seeking to have access to both WLAN and UMTS networks. We study individually optimal user-network association in an integrated WLAN and UMTS hybrid cell. The association problem is formulated within a non-cooperative game framework. In the formulation, mobile arrivals are assumed to follow the Poisson process and each mobile con...

Universal Mobile Telecommunications System (UMTS) is a third-generation cellular network that enables high-speed wireless Internet access. This paper investigates the performance of Transmission Control Protocol (TCP) over UMTS utilizing a common and four dedicated transport channels with bit rates up to 2 Mb/s. The performance of TCP was examined under varying channel conditions. Bulk data tra...

One of the key objectives of Universal Mobile Telecommunications System (UMTS) is the realization of enhanced end-user experience through the provision of rich multimedia services, ensuring in parallel an economical delivery cost for service providers. Multimedia Broadcast/Multicast Services (MBMS) framework of UMTS epitomizes the increasing popularity of such applications by efficiently delive...

The paper proposes a new simulator that supports UMTS and Enhanced-UMTS performance evaluation. Existing UMTS simulators integrate linklevel and system-level simulators, implemented using time-based simulation techniques. The proposed simulator integrates time-based link level simulations into an event-based system level simulator by extending ns-2. The simulator can evaluate parameters associa...

The goal of Universal Mobile Telecommunications System (UMTS) is the delivery of multimedia services to the mobile user. Each different service requires its specific Quality of Service (QoS) to satisfy the mobile user. In this paper, a scheduling concept for the Medium Access Control is presented that satisfies the QoS requirements. To validate the scheduling concept a typical mobile user appli...

The Universal Mobile Telecommunications System (UMTS) offers IP based multimedia applications and services with end-to-end Quality of Service (QoS) guarantee. The key component providing these services is the IP Multimedia Subsystem (IMS) that uses Service-Based Local Policy (SBLP) management for QoS control. To support end-to-end QoS, the UMTS IMS network should be scalable, reliable and flexi...

The rapid evolution of wireless and mobile communication technologies raises the challenge of satisfying different technology features in a unified architecture. For example, while WLAN technologies provide QoS and high data rates, they lack the wide coverage and powerful mobility management supported by UMTS. On the other hand UMTS users suffer from lower QoS compared to WLAN. Looking at the c...

TCP congestion control was designed and optimized for wired networks. During recent years, however, the popularity of wireless network infrastructures enabling ubiquitous Internet access, such as Universal Mobile Telecommunication System (UMTS), has grown considerably. As a consequence, many improved TCP congestion control algorithms, able to effectively operate over hybrid wired/wireless netwo...