Introduction

Overview

Emergence of all IP based wired and wireless networks for mobile services, calls for new innovations and architectural approaches. Coexistence of legacy and emerging networks such as different generations of networks based on 3GPP and 3GPP2 specifications, Wi-Fi and WiMAX, have posed new challenges to guarantee acceptable Quality of Experience (QoE) to the users. Different user environments such as fixed, nomadic, and vehicular have brought about new Quality of Service (QoS) practices and have introduced policies to best optimize the network resources and enhance user experience.

Additional challenges come from emergence of complementary technologies such as ad hoc and cellular networks. The demand for heterogeneous access increases the difficulty in providing consistent end-to-end QoS control mechanisms. We believe new and innovative QoS mechanisms must include convergence of multi-radio and multi access solutions with the state-of-the-art QoS control capabilities. The focus also needs to be on standardization of common practices to unify and provide consistent experience when users move from one network to another. Seamless roaming, seamless handoff, and selective session persistence may be the subject of discussion over the next few years. New QoS architectures for heterogeneous access will need to make certain assumptions with respect to end devices capabilities. New industry standards may be required to accommodate source as well as network initiated requests, including the ones for QoS renegotiations. Solutions may include location, behavior and resource aware admission control, policy-based management and cross-layer optimization.

The Internet is transforming from a network with the fixed best-effort packet delivery architecture to the mobile services architecture supporting differentiated QoS. The recent trend shows wide deployment of networked business applications with specific QoS requirements. In current mobile Internet, traffic flows are typically supported on the best effort basis while relying on upper layer protocols like TCP for resource sharing. This approach does not account for the diverse QoS requirements for different applications, time varying availability of radio resources and differentiation among the users. Many proposals, including the ones presented in this book, are being evaluated by the industry. For example, dynamic QoS support and intelligent controls including adaptive traffic prioritizations are proposed to be injected into the networks, applications and end devices to enable increased QoE and lower usage of the radio resources. Application adaptation roll-out is expected from the developers of the emerging mobile intelligent applications, while network adaptation is expected through the mechanisms provided by the service providers.