Quality of Service in Layered Architecture

The rapid growth and ubiquity of the Internet is a major force driving the convergence of data, voice, and video applications. However, applications like audio/video streaming, distance learning etc., demand significant bandwidth and have strict timing requirements. This necessitates the development of a new network infrastructure supporting beyond the simple best effort service that IP currently delivers. Satellite communications plays a significant role in providing access to the Internet through a hybrid — satellite/terrestrial or two-way IP network infrastructure. To provide a high data rate Internet access and global connectivity, provisioning of Quality of Service (QoS) within the next generation satellite systems is crucial. In this chapter, we discuss an end-to-end QoS layer model, QoS parameters, functional allocation, and QoS architectural standards. An overview of the core and access network QoS functions, mobile QoS followed by system availability considerations are described. This chapter provides the necessary background for conducting performance simulation to identify the critical parameters for implementation of satellite IP and/or satellite ATM networks. Some of these simulation models and performance results are discussed in parts Three and Four.