This chapter introduced the fundamental principles underlying most open source, commercial, and academic distributed tracing systems, and the anatomy of a typical implementation. Metadata propagation is the most-popular and frequently-implemented approach to correlating tracing records with a particular execution, and capturing causal relationships. Event model and span model are the two completing trace representations, trading expressiveness for ease of use.
We briefly mentioned a few visualization techniques, and more examples of visualization, and data mining use cases, will be discussed in subsequent chapters.
In the next chapter, we will go through an exercise to instrument a simple "Hello, World!" application for distributed tracing, using the OpenTracing API.