Chapter 6

Introduction to Cisco DNA Infrastructure

Network infrastructure is all around you. In any city, the tall buildings you see host anywhere from several to dozens or hundreds of networks—wired and wireless network infrastructures. They support all of the users, devices, things, and applications that organizations within those buildings use to drive and support daily activities.

The network is central to today’s business infrastructure. It is an inextricable part of how business is conducted now and into the future. But how often do you stop to consider what actually makes up that network—the actual infrastructure in which the network is composed?

The next few chapters explore the hardware, software, and protocols that make up a modern network infrastructure, and the set of capabilities that these elements enable. These are the base components of the Cisco Digital Network Architecture (Cisco DNA). And just like the architecture of a building, the structure of Cisco DNA is only as strong as its foundation, which is introduced in this chapter. Cisco DNA has a very strong foundation in the flexible networking hardware and the powerful networking software on which it is fundamentally based.

This chapter presents the following:

The fundamental Cisco DNA hardware and software architectural components are examined in greater detail in Chapters 7 through 10.

You will learn the critical areas around Cisco DNA infrastructure that allow for a greater appreciation for the base underpinnings of Cisco DNA solutions and capabilities. It is important to understand the capabilities of Cisco DNA infrastructure, in order to better understand and appreciate the capabilities and solutions that this very functional, flexible, and future-proofed architecture supports.

Picturing the Modern Network

Imagine all the data that flows over all the networks used today, worldwide. According to “Cisco Visual Networking Index: Forecast and Methodology, 2016–2021,”1 the estimated amount of all data transmitted over IP networks in 2015 totaled a staggering 72,571 exabytes per month. One exabyte equals a billion gigabytes (or a million terabytes). This is the total amount of all data flowing over IP networks that powers the world every month—data, voice, and video traffic. Assume a given month has 30 days and that the traffic is spread out equally all month long (which of course it isn’t). This works out to a sum of 223,830 Gbps, which is 223 terabits per second, every second of every day. By the year 2020, these totals are projected to grow to 194,374 exabytes per month worldwide, which works out to the astounding sum of nearly 600,000 Gbps per second. This equates to a total traffic growth of 268 percent over a very short period.

1 Cisco Systems, June 6, 2017, https://www.cisco.com/c/en/us/solutions/collateral/service-provider/visual-networking-index-vni/complete-white-paper-c11-481360.pdf.

Put another way, the total Internet traffic alone will account for almost 40 billion DVDs transmitted every month by the year 2020. Even just North America will account for 11 billion DVDs of Internet traffic within this timeframe. That’s a whole lot of Netflix, Hulu, and all the rest.

Even if you just take the business portion of this traffic, and set aside the consumer-oriented traffic crossing the Internet (the majority of which is now video), in 2015, businesses worldwide transmitted 13,982 exabytes of IP-based data per month, equivalent to a continuous data rate of 43,154 Gbps. Furthermore, by 2020, business IP traffic is projected to grow to 32,165 exabytes per month, equating to 99,274 Gbps—accounting for 230 percent growth.

These numbers are astonishing and yet, this nets out to an average data rate per human being on this planet of just 32 Kbps in 2015, growing to 86 Kbps each by 2020. Of course, not everyone is online yet, and data flows are much lumpier than this, but things are rapidly trending with the growth in mobile networking, the huge growth in the Internet of Things (IoT), and increasing pervasiveness of the Internet and IP traffic flows.

Imagine in the near future when there are tens of billions of devices online along with billions of humans. The average data rates grow in the megabits per second per person, with the future growth of virtual reality, immersive videos, ever-more-realistic online gaming, and so on. Data will be flowing across the solar system with interplanetary probes and Mars rovers. The sky is not even the limit any more.

Bringing things more down to Earth, 5.6 million commercial buildings are estimated to exist in the United States. If you could see the totality of the network infrastructure that supports today’s business environment for even a single building, the sum of it all might surprise you. It would amount to multiple tons of hardware.

Consider a 30-story downtown office tower. Assuming floor space dimensions of 150 feet × 100 feet, each floor of this office tower would host 15,000 square feet of space—or 450,000 square feet in total for the whole tower. Based on this square footage, estimate that each floor hosts 100 network cable drops (one drop per 150 square feet). This works out to 3000 cable drops in the building in total. Considering that each cable drop in such a building might be an average of 50 feet in length, and that a Category 6a cabling run of this length weighs approximately 2 pounds for the cabling itself, the twisted-pair networking cabling alone for such a building would weigh 3 tons—about the same as a GMC Hummer! This cabling would also stretch close to 30 miles if laid end to end.

Add in 50 access-layer switches at 20 pounds apiece, and a number of heavier distribution and core switches, and it could easily be close to 4 tons of network infrastructure. And that’s not counting access points, wireless controllers, WAN routers, firewalls, patch panels, patch cabling, fiber-optic cabling in the risers, racks for equipment mounting, and air conditioning systems to keep the gear cool. In short, it takes a lot of physical hardware to move bits!

This network infrastructure—the largely “invisible” items—is what supports the modern world. Even though it might not be visible, it’s critical to the operation of any modern organization or business.

This infrastructure creates networks that are designed and built for customers. Data flies over these networks at ever-increasing rates, and importance to business. People talk, send messages, and access mission-critical data over these networks. Devices, sensors, and things use the network to interact with providers, and each other.

Imagine taking away the network from your organization, or even impacting its operation in some significant way. It’s very likely that the importance of the network will quickly become clear to everyone. Yet, many people never pause to reflect on the network infrastructure—the hardware and software elements that are so crucial or how the evolution of those elements is necessary to allow organizations to keep pace with their competitors.

This chapter and the ones that follow highlight the hardware and software items that make up the modern network. This group of chapters is designed to help you understand and appreciate the flexibility, power, and performance that these hardware and software elements provide to enable today’s digital businesses. These elements comprise several key foundational underpinnings for the Cisco DNA infrastructure.

Exploring Cisco DNA Infrastructure

Let’s explore Cisco DNA infrastructure by delving into the evolving network framework itself—the base components of the network, the hardware and software elements.

It is important to understand how hardware and software elements are able to adapt to support the growing and changing requirements of an organization.

Let’s examine how a network infrastructure based on Cisco DNA principles is able to support the Cisco DNA vision. And let’s see how it solves important problems for business, building a bridge to the future.

The Evolving Network, and Why It Matters

The next generation of hardware and software elements that make up the enterprise network must support both the rapid introduction and the rapid evolution of new technologies and solutions. These network elements must keep pace with the brisk changes in the business environment and support the capabilities that help drive simplification within the network.

Today’s digitalized organizations face new challenges daily; the pace of change is only increasing. The network has to evolve. It’s the lifeblood of the business. The next few chapters explore the hardware and software foundational elements of Cisco DNA that support this evolution. This is the technology that enables the next generation of enterprise networking deployments.

This section explores the capabilities and innovations that a network infrastructure enables and supports. It also examines some of the next-generation solutions now becoming available, and the impact of these innovations on networks and organizations.

Requirements: The Need for Change

Let’s review changing organizational needs, extrapolating industry trends, and examine any shortcomings in today’s network environments to predict what may be needed in the future. Today’s network is changing more rapidly than ever. Fast-paced developments in business, academia, and our personal lives demand corresponding changes within the network.

As new protocols emerge, the network needs to be able to handle them. New security challenges arise that require a response from the organization. New applications are deployed that place new demands on the network to ensure proper access from employees. New devices are attached to the network, requiring appropriate access and traffic handling.

Note

For additional information, check out the Cisco Systems report “Digital Vortex: How Digital Disruption Is Redefining Industries” (https://www.cisco.com/c/dam/en/us/solutions/collateral/industry-solutions/digital-vortex-report.pdf). This report contains numerous examples of digital processes that disrupted seemingly entrenched industries overnight.

A striking example of digital disruption is WhatsApp, purchased by Facebook in 2014 for $22 billion. Within the space of just a few years, WhatsApp’s user base grew from a startup to an astonishing 1 billion users by February 2016. It grew by over 300 million users in the space of only 13 months. This phenomenal growth disrupted the SMS (Short Message Service) networking industry that had existed since 1996. It caused its growth to level off and even decline as WhatsApp and similar applications greatly increased in popularity. Yet what made WhatsApp possible?—the network. Benefitting from the “perfect storm” of pervasive smartphone use and widespread and speedy mobile IP data networks, WhatsApp upended the instant messaging marketplace and changed the industry’s and users’ expectations of instant messaging overnight.

There are many examples like this. Consider all the time spent today using the many communications, social media, and entertainment options, such as FaceTime for video calls, Webex for business meetings, iTunes and Spotify for music downloads and streaming, Netflix and Hulu for video, and so many others.

As the single thread that ties all of this technology together, the network is the backbone and support structure of today’s “app economy” and also of your business. As an organization evolves and new applications are introduced, demands on the network change, and the network needs to adapt.

A Cisco DNA network infrastructure is ready for these changes. Is your network ready?

Requirements: The Need for Speed (of Change)

As increased demands are placed upon the network, the technologies that are used to establish, manage, and operate the network are also changing. The pace of this change is increasing.

New applications are spun up in a modern data center within a few minutes. But is the broader network ready to support those applications end to end? Demands on the network can, and do, change dynamically and unpredictably, as mobile users move and new applications are accessed, on premises or in the cloud. Access and security requirements are altered rapidly, based on organizational change, and the business environment and threat landscape is ever-changing. In short, the needs of the organization—and of the users, things, and applications leveraging the network—continue to evolve at an ever more rapid pace.

Again, let’s revisit WhatsApp. As of November, 2016, the WhatsApp team indicated that it would expand from voice calling to video calling.2 Imagine the increased data loads that such an addition might place on your network infrastructure overnight, with video calls typically consuming many tens of times the amount of bandwidth of traditional voice calls. Consider how rapidly users will likely adopt such features as they come along.

2 https://blog.whatsapp.com/10000629/WhatsApp-Video-Calling

Or take another example. Although 75 percent of the respondents in the Digital Vortex report previously noted indicated that digital disruption is a form of progress, and 72 percent indicated that they believe that it improves value for customers, only 54 percent indicated that they believe that it improves information security. This is a large gap, and indicates an area where improved robustness and security of the network infrastructure must help to fill the breach. How will the network keep up and drive these changes?

Cisco DNA infrastructure is designed for change, able to adapt rapidly from both a hardware and software perspective to support the ever-evolving needs of the business. The flexibility provided by the infrastructural components of Cisco DNA make it uniquely adaptable to face current and future organizational challenges, with a strong focus on speed, openness, and security.

The following chapters explore the details of Cisco DNA infrastructure; its hardware and software components and capabilities and how it provides the flexible, powerful, and adaptable base necessary to support the changing face of the network and the users, things, applications, and organizations it supports.

Requirements: The Need for Simplicity

If the Internet has proven anything in the last 20 years, it is that distributed systems work. The Internet is the world’s largest distributed network. Domain Name System (DNS) is the world’s largest distributed database. These are huge, distributed systems, under multiple administrative domains, and yet as a rule they work well, are robust, and have proven to scale.

The issue is not one of reaching the limits of distributed systems. Scale, as important as it is to address, is not the problem. The concerns faced by many organizations today is that distributed systems such as networks are, by nature, complex. The risk is that, if unaddressed, the increased pace of change in organizations, along with the need to deploy, manage, and troubleshoot large, distributed network systems, bring more complexity to the tasks of the solution architect and network manager, not less.

As part of the evolution toward a next generation of networking systems to support the organization, simplification and flexibility need to be part of the deployment model, and thus need to be baked into the infrastructure of the network system. As an example, think of the car you drive. Automobiles have an immense amount of mechanical and electrical complexity. Yet, as a driver, you are abstracted away from almost everything that the car does. When you sit in your car, you are presented with a steering wheel, a few pedals on the floor, a gear shifter, and a dashboard showing some basic indications of vehicle performance. You sit in your car, start it up, and drive. This is, of course, far from the experience of a network designer and administrator. However, it is the experience necessary to provide for next-generation networks.

Abstraction, which allows for automation, is the key. In the car example, the various capabilities presented to the driver—steering wheel, basic pedals, and a simple dashboard—are all abstractions of the underlying mechanical and electrical complexity of the car. These abstractions are key to making the car “consumable.”

The value of abstractions in a network environment is equally clear. Abstractions provide simplification, enabling simplicity of operation and daily use even with upgrades and troubleshooting. To drive this simplification, the network infrastructure plays a key role.

How can we keep the sophisticated functionality of the network and build on it with new innovations while making things simpler? Again, the robust, flexible set of base infrastructural components that Cisco DNA provides is designed not only to deliver sophisticated functionality, but to do so in a simple, scalable fashion that supports the needs of current and future business models. This, of course, helps to enable new business models to flourish.

Requirements: The Need for Continuity

Networks are now ubiquitous. Users, devices, and applications expect a network that is readily available. Organizations increasingly depend on the network and, in many cases, cannot effectively operate without it.

Yet at the same time, organizational demands require change. How can you reconcile the need for business continuity with the need to implement innovative network capabilities to handle changing business functions? The answer is an evolutionary approach, which Cisco DNA’s flexible hardware and software infrastructure adopts and embraces. This stands in contrast to the approaches taken by others within the industry, which may call for wholesale “forklift upgrades” necessary to adapt to some of these changes. The evolutionary approach adopted by Cisco DNA lowers risk, saves capital expenditures, and promotes operational continuity.

By providing many functions on top of existing hardware and software that you already own, and have deployed, Cisco DNA lets you easily, and incrementally, take the first steps into an evolved network world. The nature of Cisco DNA provides significantly better investment protection. It allows more value to be wrung out of existing Cisco infrastructure investments and new deployments to continue to add capabilities over time, which increases value to the organization.

At the same time, more advanced Cisco DNA capabilities may be realized with additional or newer network hardware and software platforms that can be deployed into your network. You can add in these functions and capabilities in a step-by-step fashion, as needed to accommodate changes in your business. These platforms can help to enable new, evolved functionality within the network architecture while supporting some of the key elements within Cisco DNA.

How is this accomplished? How do the needs for operational continuity and investment protection relate to the network infrastructure in place within your organization? Or the new upgrades to your network infrastructure you may be planning for your next network refresh? The following section explores these concerns.

Cisco DNA Infrastructure Solutions

This section discusses the hardware, software, protocol, and virtualization innovations that Cisco DNA offers. Specifically, the following sections provide an overview of the following:

Flexible Hardware

In the most basic sense, networking hardware, such as a switch or router, moves data packets from location A to location B. Networking hardware examines packet headers transmitted by attached hosts such as IPv4 addresses, IPv6 addresses, Media Access Control (MAC) addresses, and so on. It communicates with adjacent network elements (using various Layer 3 routing protocols, Spanning Tree Protocol [STP] for Layer 2 connectivity, etc.) to determine how to forward traffic from those hosts to move it along to its destination. Conceptually, this is quite simple. And yet, there is so much more to it.

What happens when you need to handle new or evolved packet formats? What happens when support is necessary for segmentation such as Multiprotocol Label Switching VPNs (MPLS VPNs)? What if a need arises for a new application that demands IP subnet or Layer 2 extensions between areas of the network that have a full Layer 3 network infrastructure between them? What happens when new protocols are created, such as Virtual Extensible LAN (VXLAN), and modern network designs evolve to support these new technologies? What about the capabilities that such new protocols enable? In short, what happens when technology changes, as it inevitably will? Can the network adapt? Or will your network and organization get left behind?

Addressing these questions is critical to the adoption of new networking technologies, which include the following concerns:

The pace of innovation in the network, including the devices, users, and applications it supports, is not slowing down. In fact, it is accelerating faster than ever. In short, as business requirements change and improved sets of networking technologies emerge over time, the network needs to adapt to support them.

With traditional networking hardware, based on “hardwired” application-specific integrated circuit (ASIC) designs, the answer as to whether new network capabilities can easily be adopted to support ever-increasing requirements is generally “no,” which is not a good answer for the needs of a modern business.

Chapter 7, “Hardware Innovations,” examines ASICs in networking hardware, such as switches. Switches are typically designed for a certain set of functions and traffic handling, which they do at very high rates of speed. However, a typical switch may lack the flexibility to adapt to new network headers, functions, and protocols.

Need a new protocol? Require a new network function such as secure end-to-end segmentation or subnet extension to support a new or altered business process or a set of new network devices or services? Without a flexible hardware base such as the ones provided by Cisco DNA solutions, you may have to swap out major portions of the network infrastructure to support such new requirements, which can be a very disruptive and costly undertaking.

Alternatively, take a look at CPU-based network hardware designs, which are often seen in lower-end to midrange routers. They provide the flexibility to handle new network functions and protocols as they arise, but typically lack the performance to scale up to larger data rates, which may need to range from gigabits to tens or even hundreds of gigabits per second and beyond.

Other midrange options exist, such as field-programmable gate arrays (FPGA), which can scale up to higher data rates and provide a level of flexibility for traffic handling beyond what traditional hardwired network ASICs provide. However, the cost-per-bits-moved metric of FPGA-based solutions is often unattractive for large-scale network deployments.

So how can you provide the level of flexibility that the evolving network, and technology stack, demand as well as meet the performance and the cost goals of a next-generation enterprise network build? Chapter 7 explores in more detail the next generation of flexible hardware elements that are enabled by Cisco DNA for switching and routing infrastructures. It explains how Cisco DNA enables the rapid evolution of business and real-time network and policy enforcement that supports today’s rapidly changing business and technology environment.

Flexible Software

Cisco IOS provides the most widely deployed software stack in the networking industry. The majority of network infrastructure elements in a typical enterprise network use IOS. Most network operators are well versed on IOS-based network designs, deployment, and troubleshooting.

As pervasive as IOS is, though, it is supplemented by adjacent software stacks for specific functions. Virtualization is becoming a key technology element in the arsenal of organizations, allowing them to deploy network-based services more flexibly and rapidly than ever before. Virtualized functions and containerized applications, whether on network elements themselves or on adjacent (and typically more powerful) server platforms, provide new, exciting, and ultimately necessary functions for business.

And so, the industry moves forward. Customer network deployments move forward. New norms emerge around network deployment, operation, and support. New requirements for virtualization of network functions and solutions arise. The pace of business continues to increase, and demands on the network continue to scale.

How can current and future software stacks keep pace in a way that embraces evolutionary change, in order to ultimately reap revolutionary results? The answer within Cisco DNA is through a combination of evolution of the world’s most popular networking software, Cisco IOS, combined with new, enhanced capabilities.

IOS XE is Cisco’s next generation of IOS, evolving the most successful networking software stack into the future. IOS XE enhances traditional IOS by adding in modularity, which allows for capabilities such as patching and enhanced high availability. IOS XE also adds in componentization, which allows for more rapid and accurate implementation of new features and capabilities, enhancing software reliability and easing troubleshooting. And, IOS XE supports containerization, allowing new capabilities to be hosted on Cisco platforms as “containerized” applications.

By evolving IOS onto a new software base that provides modularity, componentization, and containerization, new capabilities are delivered, and simplicity and flexibility are enhanced. The evolution of IOS XE is discussed further in Chapter 8, “Software Innovations.”

New and Evolving Protocols

The intersection of flexible hardware and flexible software allows the creation and support of new protocols. The networking industry is in the midst of massive change. It is necessary to support the corresponding modifications in organizational requirements, capabilities, and expectations, which include the following:

As new networking protocols emerge to support these changes such as VXLAN for Layer 2/Layer 3 overlays and LISP for next-generation routing, the combination of hardware and software flexibility provided by a Cisco DNA infrastructure allows these new protocols to be accommodated within existing network footprints. This is without necessarily requiring hardware replacement and churn in order to adopt such new technologies. This in turn allows for new solutions to be deployed on network hardware elements that may already be in place that support new capabilities for business. It also provides a significant level of investment protection while lowering total cost of ownership (TCO). New protocol support within Cisco DNA is discussed further in Chapter 9, “Protocol Innovations.”

The Emergence of Virtualization

Physical network infrastructures are pervasive in today’s world. However, the world around you is also virtualized in many ways. Bare-metal servers that previously ran only a single application now host multiple virtual machines (VM), each running its own app or apps. Applications are deployed within containers. Network-based functions that were previously deployed on-premises can now leverage the cloud. Data can reside locally, or located half a world away.

The networking industry is in the midst of massive change, and virtualization plays a key role. By integrating virtualized network functions (VNFs) into a Cisco DNA-based set of network infrastructure, new capabilities and new flexibility in deployment, operation, and management are realized.

Cisco Enterprise Network Function Virtualization Infrastructure Software (NFVIS) is intended to meet this goal, in a way that meets the requirements of a next-generation organization. NFVIS and related virtualization technologies within Cisco DNA are discussed in more detail in Chapter 10, “Cisco DNA Infrastructure—Virtualization.”

Bringing It All Together

Whether functions are deployed locally on-premises or remotely in the cloud or whether they become virtualized or containerized, at the end of the day, they all need something physical to run on. When packets are moved across a desk or across the world, they might be accessing virtualized applications or attaching to virtualized functions in the cloud. However, they also need to cross a physical network of access points, switches, and routers to get there and back.

The network’s physical infrastructure consists of multiple elements, hardware, software, and the methods used to access and interface with them. Based on the current and future evolution of the business (evolving and changing needs of users, applications, and devices within an organization), the trends within the industry, and the evolution of “the possible” in technology, network infrastructures are changing more rapidly than ever before.

There is always a physical underpinning to the network, even when it is combined with a virtualized deployment. The greatest functionality is extracted when both the virtual and physical infrastructure work together. Chapters 7, 8, and 9 examine the elements of the physical network infrastructure, hardware, software, and protocols. Chapter 10 examines the virtualized components that can layer on top of, and integrate with, the physical infrastructures that make up a network.

Chapter 11, “Cisco DNA Cloud,” examines what a next-generation network infrastructure based on Cisco DNA principles looks like. It discusses the solutions it provides and how it directly supports the broader organizational goals of simplification, flexibility, investment protection, and lower TCO.

Summary

This chapter introduced the requirements of the modern enterprise network and provided an overview of the current state of the networking industry and future trends. It examined the evolving enterprise network and corresponding needs for (rapid) change, simplicity, and continuity.

This chapter also introduced the concepts and capabilities provided by the infrastructure supporting Cisco DNA, including the following:

The following chapters explore the new innovations that Cisco is driving in the Cisco DNA network infrastructure—powerful, flexible hardware, software, and virtualization components—to benefit your business as it digitizes.

Let’s get started! Turn the page to start diving into the first Cisco DNA infrastructure building block, focusing on hardware innovations, including the next generation of flexible hardware elements.