Quality-of-Service degradation strategies in multimedia wireless networks

Analysis of adaptive bandwidth allocation in wireless networks with multilevel degradable quality of service

“…1. Since the connection lifetime is mainly decided by the communication contents, such as the length of conversation during a phone call or the size of a transferred file, 1 while the cell-sojourn time is decided by the aforementioned factors, we assume that these two random variables are independent. Thus, the probability that a mobile user will experience handoffs H times can be calculated as…”

“…For example, generic video telephony may require more than 40 Kbps, but low-motion video telephony requiring about 25 Kbps may be acceptable [1]. From the standpoint of a system administrator, this property provides an alternative for resource planning, especially for bandwidth allocation in wireless networks.…”

“…Thus, a system could free some bandwidth for new users by lowering the QoS levels of existing users. Sen et al [1] proposed an optimal degradation strategy by maximizing a revenue function and Sherif et al [3] proposed an adaptive resource allocation algorithm to maximize bandwidth utilization and attempted to achieve fairness with a generic algorithm.…”

Utility-based Adaptive Resource Allocation in Hybrid Wireless Networks

“…The work in [6,17] employs bandwidth borrowing and degradation as part of AC with each connection request submitting acceptable max and min resource requirement. In [20] an AC algorithm is proposed that uses controlled QoS degradation of on-going calls to manages a tradeoff between resource allocation of on-going calls and new calls. A similar tradeoff is managed by an AC algorithm proposed in [19] using Guard Channel policies.…”

Modelado y evaluación de la gestión de recursos en redes móviles celulares.

“…Por ejemplo, una aplicación de video-telefonía genérica utiliza más de 40kbps, sin embargo para una video-telefonía de baja movilidad pue-de ser suficiente con 25kbps. Con esta tasa se ofrece un calidad aceptable para este tipo de aplicación, tal y como se observa en [SJBD98]. Cuando estas aplicaciones piden una conexión a la red, el usuario especifica un rango discreto -o jerárquico-de tasas con el que puede trabajar la aplicación, definiendo una serie valores, desde el número mínimo de recursos (MinBW) hasta el máximo de recursos (MaxBW).…”