Improving user-perceived QoS in mobile and wireless IP networks using real-time adaptive multimedia applications

Adaptive applications are a key concept to take into account when dealing with multimedia internetworking in wireless and mobile environments, in which network conditions may change abruptly and not always due to congestion - as it happens in fixed networks - but also to interference, mobility and so on. This paper presents an adaptation architecture which allows applications to minimize the impact of adverse and changing network conditions, by using self-adjustment techniques at high layers, obtaining information from the network. The objective is maintaining the quality of service (QoS) perceived by the user at an acceptable level. Results are presented by means of some tests in a typical ad-hoc scenario.