Just a few years ago, software-defined wide area networking (SD-WAN) was a “new” technology just breaking into the awareness of the IT market. It arrived at the time when enterprises were changing from moving applications and data to “a” cloud platform, to expanding to multiple clouds. SaaS application providers for CRM, HR, finance, and supply chain were firmly established as critical business resources that need to be accessible from anywhere via direct internet connections.

These were all positive changes, but not without a certain amount of pain. In particular, the traditional WANs were struggling with these new demands. The WAN architecture worked well when all connections from branches and a distributed workforce flowed back to a central data center through MPLS lines, where security policies were also applied. But the hub and spoke WAN architecture broke down as more direct internet connections were needed to access multi-cloud resources and SaaS applications. Continuing to backhaul all traffic to data centers before routing to internet cloud applications results in increasing MPLS costs, bandwidth inefficiencies, increased latency, and poor application quality of experience. In addition, WANs were often composed of components from multiple vendors, limiting the visibility and control over performance and troubleshooting.

SD-WAN was designed to answer these challenges. The technology provides methods to prioritize critical business traffic and take advantage of internet broadband connections—previously used for backup and redundancy—to connect directly to multicloud resources. SD-WAN simplifies the management of the wide area network fabric with a controller-first overlay that is independent of transport layers—MPLS, Ethernet, internet, leased lines, DSL, LTE networks, and soon 5G. SD-WAN controllers intelligently choose among the available transport mediums to deliver the best application performance as defined by IT service level agreements (SLA).

The Evolution of Cisco SD-WAN

In the early stages of SD-WAN, engineers at Viptela developed a flexible SD-WAN architecture based on cloud management and controllers (vManage and vSmart) and virtualized network function edge routers (vEdge). Their version of SD-WAN followed the same software-defined architecture as Cisco’s Digital Network Architecture (DNA), separating the Data, Control, and Management Planes for maximum flexibility. Viptela’s architecture made it a natural extension to Cisco’s Intent-Based Networking vision. Viptela’s visionary team and technology were acquired by Cisco two years ago this week—August 1st to be precise. Rapid innovations and integrations have been ongoing ever since.

Many of the innovations we’ve added come from listening to our enterprise customers who are seeking a solution to unite multi-domain cloud resources across a distributed organization. We hear that they need ways to simplify the interconnection of the domains with unified access and security policies applied across campus, branch, and cloud. Let’s look at the capabilities we’ve added to make Cisco SD-WAN powered by Viptela an enterprise-class platform that meets these needs and more.

Cisco SD-WAN Architecture

Looking Deep Inside SD-WAN Operations

Networks are becoming much more complex as organizations tie data centers, remote branches, and a distributed workforce with multi-cloud applications using connectivity options like direct internet and LTE that are outside the direct control of IT. Therefore, it’s important to be able to see inside the WAN to monitor, measure, and adjust the parameters affecting performance. That’s why one of the first capabilities Cisco added to the SD-WAN stack was Cisco vAnalytics, a cloud-based tool for monitoring and analyzing SD-WAN performance via the vManage portal. vAnalytics provides specific information that enables IT to readily monitor bandwidth usage, application performance, and detect anomalies based on baseline application usage. Going forward, vAnalytics will incorporate more artificial intelligence and machine reasoning, as was recently introduced in Cisco AI Network Analytics.

Expanding SD-WAN to Cisco ISR/ASR Edge Routers

When considering a new technology, IT leaders prefer to avoid the need to “rip and replace”. Cisco alleviates that concern by making SD-WAN available to run on over a million ISR/ASR routers that are already serving branches and campus networks worldwide. Cisco IOS XE, released a year ago, provides an instant upgrade path for creating cloud-controlled SD-WAN fabrics to connect distributed offices, people, devices, and applications operating on the installed base of ISR/ASR routers. At the same time, we added the ability to run SD-WAN as virtualized network functions in a cloud provider’s IaaS platform, providing even more flexibility to quickly extend SD-WAN to the cloud.

SD-WAN Full Stack Security Protects Branch Data and Cloud Applications

When using the internet to connect branches and remote employees with cloud applications, sensitive data could pass over multiple networks outside of the control of IT, increasing security risks. Protecting the data while making it available on-demand to the workforce presents a series of technical and enforcement challenges.

To allay those concerns, Cisco, one of the top worldwide providers of network security solutions, integrated full-stack security into SD-WAN running on edge routers. Cisco SD-WAN Security is built-in, not composed of separate bolted-on components from a disparate variety of vendors, making security easy to manage via the vManage cloud portal. By integrating an application-aware firewall, intrusion detection and prevention, advanced malware protection, and Cisco Umbrella DNS cloud security layer, data security is easily and consistently maintained across branches.

In addition to securing branch and distributed workforce connections, IT wants to holistically address security concerns across multiple domains. That means setting access and security policies once and having them permeate the enterprise across data center, campus, and branch, to the cloud edge where IoT devices increasingly need to do local processing. Because Cisco designs security using an end-to-end perspective, creating cross-domain policies is not only possible, but a necessary capability as applications, data, and devices become more distributed and the workforce more mobile. Cisco is enabling unified policy management by linking ACI in the data center with SD-Access in the campus and SD-WAN for branches so that segmentation and security are applied consistently all the way from people and devices to the application hosting cloud platforms.

SD-WAN Cloud OnRamp for CoLocation Consolidates Regional Branch Connectivity

With SD-WAN making it simpler to configure and manage connections from branches to cloud resources, it’s just one more step to consolidate many regional branches under a common colocation facility. Creating an onramp connection from each of many branches to a colocation facility hosting a virtualized SD-WAN reduces the need for edge routers at each location and centralizes the management while providing all the same security and transport layer options.

In many cases, the target cloud providers and SaaS applications reside in the same colocation facility, thus shortening the paths and reducing latency to further improve application performance for potentially dozens to hundreds of branches. Additional virtualized SD-WAN instances in the colocations can also be quickly spun up to connect new branches as quickly as needed. SD-WAN Cloud OnRamp for CoLocation joins Cisco’s Cloud OnRamp for IaaS and SaaS to extend connectivity management from branches to multiple cloud platforms to provide granular control over application quality of experience via vManage.

Evolution of SD-WAN Continues for Revolutionary Results

All these innovations integrated into Cisco SD-WAN powered by Viptela are fundamental to building an Intent-Based Network. Built-in network intelligence translates business intents into network actions that provide consistent access policies, security for devices and data, and a high-quality application experience for a distributed workforce. Integrating multicloud compute resources with cross-domain access drives a revolution in business as enterprises strive to connect information to people anywhere at any time to improve employee productivity and customer experience.

National Instruments, an international leader in test and measurement systems, implemented SD-WAN to solve a number of IT and business problems. Like many organizations with a globally distributed workforce, the network supports communication services, software distribution, and access to applications and data resources among worldwide sites. The existing WAN greatly constrained video conferencing, slowed large software transfers, and couldn’t provide acceptable application performance. Implementing SD-WAN turned those issues around by:

  • Reducing MPLS spending by 25% while increasing bandwidth by 3,075%.
  • Categorizing traffic by function and type, sending backup traffic over the Internet under an SLA, eliminating bandwidth bottleneck on MPLS circuits.
  • Reducing the time for software updates to replicate across the network from 8 hours to 10 minutes.
  • Adding new internet-based services used to take months, with the agility of SD-WAN new services can be deployed in the cloud immediately.
  • Eliminating the need for call admission controls and limiting video quality for conferencing

Enterprises are gaining advantages such as these by upgrading their aging WAN technology to SD-WAN. It’s not just cost savings by supplementing or replacing MPLS with direct internet connections that is motivating the transition to software-defined WAN architecture. It’s also about gaining flexibility and stability with intelligent, continuously monitored connections to multicloud resources and SaaS applications that are fueling the transition. In a software-defined world, people, devices, applications, and data are all securely connected to ensure organizations run efficiently as they tackle digital transformation projects. How will you use SD-WAN to support your digital revolution?

For additional information

New Perspectives on Software-Defined WAN

Cisco SD-WAN powered by Viptela Market Leadership

Cisco SD-WAN web site


Anand Oswal

No Longer with Cisco