: It provides OAM&P (operations, administration, maintenance and provisioning) functionality. It acts as the watchman that monitors the network and takes actions to rectify in case something goes wrong with the network on a 24/7/365 basis. 1.1.3 Technology Management TM deals with a number of soft elements of the mobile communications business. This field is vast and contains both technical and people elements, including, but not limited to, technology development, knowledge management, managed services, and SO on. 1.2 Book Overview We have made an attempt in this book to give a holistic picture of a Next Generation Mobile Commu- nications ecosystem. Holistic means that we not only discuss technologies, standards and networks, but also the technology management component which is necessary to manage underlying technologies and networks in an effective fashion. The book consists of 13 chapters including the current chapter that is, Chapter 1 Introduction. It provides details of various radio, transmission, core network, and OSS technologies and standards. Additionally, a chapter is dedicated to the principles of technology management. Briefly (and as shown in Figure 1.2) some information about the chapters is as follows: 1.2.1 Chapter 2 OFDM and OFDMA Chapter 2 looks into OFDM (orthogonal frequency division multiplexing) and OFDMA (OFD Multiple Access) techniques. OFDMA is at the heart of both 3GPP (Third Generation Project Partner) EPS and IEEE (Institute of Electrical and Electronics Engineers) WiMAX technologies. OFDMA is a departure from CDMA which is used in all the three 3G systems mentioned earlier. OFMDA is also the proposed multiple access technique for 4G mobile systems. 1.2.2 Chapter 3 3GPP Evolved Packet System (EPS) Chapter 3 discusses 3GPP EPS technology that consists of a new radio access called E-UTRAN (En- hanced UMTS Terrestrial Radio Access Network) which is commonly known as 3G-LTE (Long Term Evolution) and an enhanced core network called EPC (Enhanced Packet Core). The radio interface of EPS t