Summary

The OSI reference model facilitates modular development of communication products, thereby reducing time to market for new products and facilitating faster evolution of existing products. Standards organizations often leverage the OSI reference model in their efforts to specify implementation requirements for new technologies. The ISO does not guarantee interoperability for OSI-compliant implementations, but leveraging the OSI reference model does make interoperability easier and more economical to achieve. This is increasingly important in the modern world of networking.

The protocols discussed in this chapter do not all map to the OSI reference model in a neat and clear manner. However, the functionality provided by each protocol is within the scope of the OSI reference model. The most important things to understand are the concepts presented in the OSI reference model. That understanding will serve you throughout your career as new networking technologies are created. The OSI reference model provides network engineers with the proverbial yardstick required for understanding all the various networking technologies in a relative context. The OSI reference model also brings clarity to the complex interrelation of functionality inherent to every modern networking technology. The OSI reference model is used throughout this book to maintain that clarity.