In this book we summarize important developments in telecommunications with a focus on Signalling System No. 7 (SS 7) network reliability. But why is SS 7 network security and reliability so important? According to the Open Systems Interconnection (OSI) model the term “network” refers to the Layer 3 network service, which is offered by the Message Transfer Part (MTP) and Signalling Connection Control Part (SCCP) to higher layers. An SS 7 network outage results in a breakdown of signalling between the individual nodes of the network, so that telecommunication network services are no longer available to customers. Apart from the tremendous nancial damage to the network operator, the social consequences of such a network breakdown cannot be underestimated. Since the MTP is the central part of the SS 7 network, it is of crucial importance for network security and reliability. The MTP is published in different versions and should now be what we call “stable”. Is it really stable? Does it work properly in real networks? Does it t new requirements so that no further changes within the MTP are needed? Various different implementations have existed for a long time and are used in national as well as the international network. Due to this, an objective is not to p- form any further changes within the MTP in order to avoid compatibility problems with existing and running systems. Experience shows that compatibility problems are always related to further development of the MTP.

In the last decade, the technology, regulation, and industry structure of our information infrastructure (telephone services, cable and broadcast television, and myriad new data and information services) have changed dramatically. Since the break-up of AT&T's Bell System monopoly, telephone services in the United States are no longer purchased from a single firm. Advances in fiber optics, wireless communications and software-controlled switching are changing how communication services are provided. As the global economy grows more dependent on a hybrid mix of interconnected networks, public officials in the US and abroad are relinquishing control of the market. All of these changes are affecting the quality and reliability of the telecommunications infrastructure, but informed discussions of the public policy and economic issues are scarce. Deregulation and increased competition have lowered prices, but have service quality and reliability suffered? Do advanced network technologies which make it possible to offer a dizzying array of new services increase vulnerability to system-wide failures? Who should or is likely to bear the costs of increased -- or decreased -- service quality? This volume tackles the economic and public policy issues raised by these difficult questions for an audience of industry executives, scholars, and policymakers. Leading scholars and analysts examine such issues as the effects of network ownership on incentives to invest in quality improvements and/or strategies for quality-differentiated pricing in tomorrow's broadband, integrated networks. They analyze the quality of current telecommunications networks and the impact of re-regulation on cable television quality. The contributions range from new microeconomic theory to new empirical research. As such, the volume makes a valuable contribution to the public debate on network quality and reliability. It will be useful both as an introduction to newcomers and as a resource for more experienced researchers. As regulatory, industry and national barriers to integrated communications fall, these issues are likely to become even more important. The research presented here provides a solid foundation for further discussion.