Software Defined-WAN for the Digital Age

A Bold Transition to Next Generation Networking

David Wang

• Publisher: CRC Press
• Year: 2018
• ISBN:
  9780429773525
• Edition: 1
• Topic: Computer Science
• Subtopic: Information Technology
• Index: Computer Science

SD-WAN is an advanced networking approach that creates hybrid networks to integrate broadband or other network services into the corporate WAN, not only just handling general business workloads and traffic, but also being capable of maintaining the performance and security of real-time and sensitive applications. This book posits that Software Defined (SD) WAN is the answer to questions such as what changes can be made to the networking sector? What innovations can make WAN, which plays a vital integrated part of the cloud ecosystem, more cost effective, performance robust, provisioning efficient, and operation intelligent?

1

Highlights of SD-WAN Evolution

A Conversation with an SD-WAN Evangelist

Software-defined wide-area network (SD-WAN) for the first time turns the network functions into an intelligent ecosystem.

At the end of 2017, I got a chance to have an insightful conversation with an SD-WAN solution evangelist and we talked about SD-WAN’s start-off, status quo, and future trends.

Author (A): I’ve heard you are a strong advocate of SD-WAN in terms of technologies and services.

Evangelist (E): Yes, that’s right. I’ve spent past 5 years introducing and promoting SD-WAN sometimes as an alternative, sometimes a supplement to the legacy WAN solutions, with MPLS in particular.

A: What exactly the amazing changes do you see from SD-WAN? What’s new in it?

E: Well, the biggest change is that SD-WAN is making WAN smarter and agile from the network function perspective, and less costly with shorter installation time from the business operation perspective. An analogy would be that the network used to function just like a machine, or it’s made of many pieces of machines like routers, switches, gateway, fire walls, CPEs (customer-premise equipment), and accelerators along the network. Are they controllable and operational? Yes, but often in a difficult, slow, and less effective way, because imagine when you have these so many machines and devices to manage.

A: So, SD-WAN is not functioning like a machine anymore?

E: Not like an old-style machine. I would say SD-WAN for the first time turns the network functions into an intelligent ecosystem. For example, human being is an intelligent ecosystem, our heart pumps blood and maintains the life, while our brain controls thinking and manages the actions, in a central manner. Our body obtains energies from the heart and follows the right instructions from the brain.

A: How is this like the way SD-WAN works?

E: Now advanced software and virtualization technologies (called SDN and NFV) allow us to simplify the hardware devices like routers and firewalls, decouple the data plane and control plane of routers, and manage the network from a central orchestration point with great scalability. The result is network becomes more organic (vs. mechanic), automatic (vs. manual), and responsive (vs. numb) in its performance and management. SD-WAN now makes the so-called edge network possible, which better serves the end users.

A: That sounds very exciting. Still some folks think SD-WAN as just another buzzword and its service has no significant difference with like such existing solutions as network optimization.

E: Such notion is incorrect. Network optimization’s goal is to make the most effective use possible of the limited bandwidth available across the WAN link by applying several techniques like deduplication, compression, reduced latency, and caching to name a few. SD-WAN on the other hand, specializes in real-time network scenarios, accounting for jitter, latency, and packet loss to ensure that traffic is traveling optimally across the WAN along the best routes.

A: Can these two services work together?

E: Yes. Some SD-WAM offers include the optimization feature, and some offers makes it optional if the clients have missional critical and real time traffic to send through. The difference is SD-WAN allows more control over the holistic network operations instead of just a single route.

A: OK, very helpful. Another puzzle people have is that often SD-WAN will run an overlay on top of public Internet service. Hence is SD-WAN reliable enough for enterprise class of communications?

E: I would say SD-WAN is reliable in most cases for two key reasons. First, its central orchestration, control, and intelligent routing would allow traffic to go through the best routes of the Internet and reach the destination as a private network like MPLS can handle. Second, the fast growing all fiber network infrastructure and enhanced Internet technologies as being deployed in most of developed regions and countries will help to make the quality, availability, and performance of public Internet close to the private IP network.

A: Then what’s its difference with the IPsec VPN that we are already familiar with?

E: Good question. As for IPsec VPN, the tunnel, encryption, and overlay idea are pretty similar to SD-WAN. But IPsec VPN is just a secured tunnel without much traffic management mechanism, while SD-WAN offers much more and takes care of lots of network complexity with building redundant tunnels, monitoring the quality of the tunnels and failing over.

A: How has SD-WAN been doing in the market?

E: I would say 2012–2013 was about the SD-WAN concept kickoff; 2014–2015 was initial productization and technology polishing up. 2016–2018 is about rolling out the service offer both from technology vendors and telecom service providers. The adoption is really heating up.

A: What’s your prediction for SD-WAN in the next 3–5 years?

E: SD-WAN solution will take off and come as a new normal for WAN solutions. I don’t see SD-WAN will completely replace MPLS, rather it will work as a supplementary alternative in some cases especially for regional and long-haul traffic. This is like you take an airline to a destination, you would have economy, economy plus, business, and first-class seating choices. Some business mission critical data may still be better off routing over MPLS, while other traffic will be fine riding on SD-WAN. Anyway, enterprises now have more options for their WAN services.

A: From this sense, do you still see SD-WAN disruptive enough as a next-gen network solution?

E: Of course. Some companies may prefer MPLS + SD-WAN hybrid, while others may totally de-plug MPLS and just use SD-WAN over the public Internet. Overall SD-WAN will significantly lower the WAN service cost, enhance agility, performance, and security, plus directly linking business to the Cloud in high speed. Although it may not completely take over MPLS, 65%–75% taking away of legacy MPLS traffic is very possible. By doing so it would become quite disruptive in the WAN service evolution.

A: So, can we say SD-WAN will be a new network solution most enterprises can’t do without from now on?

E: Yes, we can. I would prefer to call it a new “digital platform.”

Call for a New WAN of the Digital Age

The Fourth Industrial Revolution or Industry Revolution 4.0 is underway, and it is a name for the current trend of automation and data exchange in manufacturing and IT technologies. It’s agreed that this new revolution, as illustrated in Figure 1.1, will be marked by such advanced technologies as artificial intelligence (AI), robots including unmanned vehicles, digital transformation and ecosystem like smart Cloud computing, big data, Internet of Things (IoT), 5th Generation (5G) cellular, etc.

Figure 1.1 The fourth industrial revolution.

Digital transformation is the ability to orchestrate apps, networks, and devices to provide seamless access to digital services for end users, where the network is the foundation of any digital transformation effort, because network is the one thing that connects everything.

The next-gen wide-area network (WAN) that connects local area networks (LANs) together over geographic areas must evolve to support digital transformation. The next-gen WAN includes both wireline and wireless, in the form of all fiber optic data networks, as well as 5G wireless technology and solutions.

Today many large enterprises have started to establish digital transformation initiatives and task teams to drive their innovations and decision-making. Leading initiatives include AI/machine learning, IoT, hybrid Cloud architecture, and the SD-WAN that this book intends to cover. All these are shaping the next-gen IT and networking ecosystem.

Cloud Apps and Smart Networking as Drivers

Now new applications in the nature of digital transformation are taking over as major WAN bandwidth consumptions.

Today, as a result of digital transformation, the WAN is responsible for carrying a wide array of traffic for many applications for streamlined collaboration and communication within an organization and across organizations. Also, Cloud-based IT operations have changed the way data traffic moves and the location where these applications are hosted.

In the past, corporate voice, data sharing, web activities, and video conference made the mainstream of WAN traffic. Now, new applications in the nature of digital transformation are taking over as major WAN bandwidth consumptions.

According to Enterprise Management Associates (EMA) research, big data traffic now tops the list of applications that consume the most WAN bandwidth, about 30% of the overall network traffic. Storage backups/restores consumption comes the second as 28%. Cloud-native applications and external Cloud applications were each cited as the top consumer by 24% of respondents, placing them third on the list of top bandwidth hogs.^*

The Cloud-based applications that are essential for modern businesses have drastically different traffic patterns and volumes compared to traditional on-premises applications and require high-bandwidth and low-latency connections, calling for a robust new WAN for the digital age, with the following key characteristics:

Handling Cloud-Centric Traffic

Today’s Cloud-centric traffic flow in general includes Cloud-based application like Office 365 and Gmail, mobile data and videos, big data analytics, and Cloud-hosted solutions like a virtual call center. But the existing enterprise WAN is a highly centralized, controlled, and self-contained IT environment with static hardware-based networking. It is neither designed to handle such Cloud-centric traffic nor cost prohibitive in handling such traffic.

Effective Cloud operations would depend on a robust and reliable network in place between the Cloud and end users and the next-gen WAN must become a more distributed, fragmented, and dynamic ecosystem.

Smart Routing and Security Capability

The new WAN should get smarter with such strong capabilities like allowing intelligent and application-based routing, network optimization, active load balancing, latency and packet-loss conditioning, blackout and brownout detection, fast session or packet level failover, and security real-time monitoring, isolating, and resolving. Only software based central control with the hardware disaggregation will make such advanced capabilities possible.

Cost Reduction for Both Service Providers and Enterprise Users

The new WAN should help businesses reduce cost in two ways: service cost and opportunity cost. Provided as a fully managed service globally, the new WAN should ensure enterprises save on subscription cost, and the solutions delivered through network overlay, virtualization, and the Cloud should help reduce capital expenditures. That is, on-premises infrastructure is no longer required to launch the new WAN model.

The new WAN meanwhile ensures the service providers save network maintenance and management costs and improves uptime with the threats and potential costs of downtime reduced. In this way it enables enterprise and service providers IT resources to be free of network routine work and focus on more strategic business initiatives.

Agility in Deployment and Provisioning

Legacy network technologies like Multiprotocol Label Switching (MPLS) are very inflexible, and often deploying a new site or location can take 60–120 days, negatively impacting business expansion and productivity. In contrast, the market expects the new WAN deployment can be initialized in days and upgraded or changed in hours. For CPE deployment, virtual CPE (vCPE) with thin and plug-and-play DIY (do it yourself) capabilities are preferred over the traditional CPE box that required technicians on site for installation, testing, and launch.

Branch Office Optimization

The trend is that most enterprises are swit...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Table of Contents
• Preface: Debut a New WAN
• Acknowledgments
• Introduction: SD-WAN—A Game Changer for Network Solutions
• Chapter 1 Highlights of SD-WAN Evolution
• Chapter 2 Adoption of SD-WAN Solutions
• Chapter 3 Launch of SD-WAN Service
• Conclusion: Toward Fully-Fledged Next-Gen Networking
• Glossary of Networking and SD-WAN Solutions
• About the Author
• Index