issues around intellectual property rights. SDOs exist to drive continuous innovation, feature developments, and standardization across in- dustry deployments, and their contribution to connecting the world is incalculable. Now that you have an overview of the organizations that define the solutions for the timing and synchronization problems that the industry faces, it is time to look at the key components of the tim- ing solution and the metrics used to quantify their performance, as described in "Chapter 5. Clocks, Time Error, and Noise". Chapter 5. Clocks, Time Error, and Noise In this chapter, you will learn the following: Clocks: Covers clocks, clock signals, and the key components of clocks. Time error: Explains what time error is, the different types of metrics to quantify time error, and how these metrics are useful in defining clock accuracy and stability. Holdover performance: Explains holdover for clocks, applicable whenever a synchronization reference is temporarily lost, and why the holdover capability of a clock becomes critical to en- sure optimal network and application functioning. Transient response: Examines what happens when a slave clock changes its input reference. Measuring time error: Describes how to determine and quantify the key metrics of time error. In earlier chapters, you read that any clock can only be near perfect (none are perfect)-there are always inherent errors in clocks. In this chapter, you will discover the various components of a clock and understand how these components contribute to removing or introducing certain errors. Because these errors can adversely impact the consumer of the synchronization services (the end application), it is important to track and quantify them. Once measured, these errors are compared against some defined performance parameters to determine how much (if any) impact they have on the end application. This chapter also explains the different metrics used to quantify time error and how to measure them. 5.1 Clocks In everyday usage, the term cloc