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MIDDLEWARE NETWORKS- P2

MIDDLEWARE NETWORKS- P2: The material in this book is presented in three major parts: IP Technology Fundamentals, IP Service Platform Fundamentals, and Building the IP Platform. Part I of IP Technology Fundamentals presents key technologies and issues that lay the foundation for building IP service platforms. | This page intentionally left blank. TEAM LinG - Live Informative Non-cost and Genuine Chapter 2 Technology Overview This chapter lays out the background needed to understand IP service platforms and in particular the synergistic technological developments that are transforming the communications industries. The spectrum of the interrelated topics is very broad. We view them from the unifying perspective of network middleware that spans the gamut from the physical network fabric to the applications themselves. In this chapter we focus on the key technologies needed by the IP service platform and how these technologies are directly impacted by such a platform. We also identify their significance and relationships to other technologies. Beginning with developments in the circuit-switched networks that make up our telephone systems we then explore their relationship to packet networks - such as the Internet - that carry our data in a multitude of forms and the services these networks offer. Coincident innovations in the software industries extend the client and server technologies and thus imbue the Internet with a dynamic and interactive presence. From this technological mosaic emerges the substrate for reliable systems enabling businesses and consumers through the 21St Century. 2.1 Public Switched Telephone Network PSTN To most of us the oldest and most pervasive communication network in the world is the Public Switched Telephone Network PSTN . This is the familiar global voice telephone network that provides telephone to anyone with a telephone and access rights. Today PSTN spans every country and territory in the world. Since the invention of the telephone in the late 1800 s PSTN has steadily grown out of the original Bell System network developed by AT T. In the U.S. it is made up of 196 geographical local access and transport areas LATAs that are serviced by one or more Local Exchange Carriers LECs . Some of the well known LECs are GTE Ameritech NYNEX Bell .