 you will learn the following: Use of synchronization in telecommunications: Provides an overview of the use of synchron- ization in telecommunications and especially in mobile communications. This discussion is somewhat historical but explains the position the industry finds itself in today. Use of time synchronization in finance, business, and enterprise: Gives some examples for the scenarios where time synchronization is a necessary tool in the corporate and enterprise space. Industrial uses of time-power industry: Covers an example for the application of synchron- ization to an industrial segment, namely the power ("smart grid") industry. "Chapter 1. Introduction to Synchronization and Timing", introduced some basic concepts of time, including the different forms of synchronization and how they are applied. This chapter covers more of the practical uses of time synchronization, including some historical background, before moving on to pre-5G mobile use cases that are already deployed. "Chapter 10. Mobile Timing Re- quirements", covers 5G mobile in more depth. The standards for synchronization were defined starting several decades ago, and they are still ap- plicable to many widely deployed use cases of today. For example, the synchronous Ethernet (SyncE) standards can be directly traced back to standards published on traditional legacy networks like synchronous digital hierarchy (SDH) from the ITU-T and synchronous optical network (SONET) from ANSI. If your application area is circuit emulation, where one replaces time-divi- sion multiplexing (TDM) networks with IP/MPLS packet technology, then these "legacy" TDM standards are still current and relevant. "Chapter 4. Standards Development Organizations", shares much more information on the standards organizations and their roles. 2.1 Use of Synchronization in Telecommunications Synchronous communications arose with the adoption of TDM digital circuits (such as E1 and T1) being used to interconnect equipment over long distances. To improve the throughput and qua