The world is changing, and changing fast. We have seen so much technological innovation in the last decade that we might not have witnessed in the previous century. This rapid growth has impacted all spheres of our lives, and has changed the way we communicate and interact with other people, even machines; it has changed the way we conduct business with our partners and customers; it has changed our lifestyles, changing the definition of luxury and necessity.

We have seen conventional business models being toppled by new innovative business models; for example, Uber is changing the way we have recognized the taxi industry for centuries. We have seen an evolution of highly profitable new companies that own minimal assets, for example, online shopping giants such as Alibaba, Amazon, e-bay, and Airbnb. There has also been a change in the way new...

Enterprises need to build on a foundation that can help innovate at speed, keep up with change, and prepare them for what can come in the future. Digital transformation requires a digital-ready infrastructure, which is simple, intelligent, automated, and secure. There are multiple elements of the digitization infrastructure of an organization as we will see in Figure 1 next. We can broadly classify the infrastructure into three parts:

• A host of input and output systems that interact with the human world. This would include IoT systems (such as wearable sensors, the sensors in vehicles, homes, and manufacturing plants), mobile systems, CCTV cameras, and environmental sensors.
• The underlying...

We have discussed how networks should behave, and the services that a network should deliver for a new age IT infrastructure. This section talks about network design requirements and the various characteristics that should be considered while designing and implementing a network. Most of these have been the basic guiding principles even before the digitization wave, which shows that these principles have stood the test of time. A network that has to meet the requirements of a dynamic organization, however, has new principles that need to be considered such as agility and programmability. This section focuses on the different parameters that can be used to measure the effectiveness of the network design.

Cisco has been at the leading edge of networking and enabling its customers to adopt technologies that help them prepare for the future. In the wave of digitization, SDN, NFV, cloud adoption, analytics and orchestration, Cisco has come out with an architecture called the Digital Network Architecture.

Cisco's Digital Network Architecture (DNA) is an open, extensible, software-driven architecture that accelerates and simplifies your enterprise network operations. The fundamental principle of DNA is to enable a software-centric network infrastructure that can be changed to meet business needs.

Cisco's DNA delivers the same consistent experience to wired users, wireless users, and remote VPN users, and uses advanced analytics to provide rich insights into the network.

Cisco's DNA is based on the following key pillars:

• Virtualization...

In this chapter, we discussed the changing role of networks in a digital world, the various challenges faced by networks because of dynamic business environments, and how networks can be adapted to these challenges by using a structured approach to network design.

We looked at the different characteristics of good network design and what they mean from an operations perspective.

In the next chapter, we will delve deeper into how to accommodate the desirable characteristics while designing the network. We will cover the different parts of an organization's IT network and discuss the functions of each part of the network before we drill down into each part individually in later chapters.