Connection-oriented Networks: SONET/SDH, ATM, MPLS, and Optical Networks

This book explores a number of connection-oriented packet-switching networks and circuit-switching networks. These networks, though seemingly different, share common networking principles, and in some cases, one more recent network builds upon an older one.In this book, we explore two connection-oriented packet-switching networks: ATM networks and multi-protocol label switched (MPLS) networks. ATM is a legacy network that was developed in the late 1980s and early 1990s. It is used in the backbone to transport IP traffic, in access networks (such as ADSL-based networks and passive optical networks), and in cellular telephony. The MPLS architecture is an extension of ATM, and must be used to introduce quality of service (QoS) in IP networks.Two circuit-switching networks – SONET/SDH and Optical Wavelength Routing networks – are also presented in this book. SONET/SDH has been around for a long time, whereas optical wavelength routing networks are relatively new. SONET/SDH is the underlying transport network of the telephone system and is used in all modern packetswitching networks, such as IP and ATM. Wavelength routing networks are also circuitswitching networks since the transmission of data is done using optical circuit-switching connections, known as lightpaths. We also present a new optical networking scheme, which has not yet been standardized, known as optical burst switching (OBS), which can be seen as lying between packet switching and circuit switching.
Finally, the book contains a chapter on access networks, such as ADSL-based networks, cable modems, and ATM passive optical networks, and a chapter on voice over ATM and voice over MPLS.