Evolution Of SD-WAN

In 1997, the first IETF MPLS working group was formed. MPLS technology was evolving very fast and everyone in the industry was busy in writing standards for Layer-3 VPN, Traffic engineering and other areas in MPLS. Internet was growing faster than ever and by Year-2000 MPLS became a de-facto standard for connecting critical network for organizations.

In 2018, almost 2 decades later, big-data, machine learning, and artificial intelligence have taken center stage and it has posed new challenges to network architects. Demands on current networks are evolving faster and large networks are observing exponential growth rate in terms of bandwidth due to cloud computing, mobile devices, and video usage. Some of these trends helped the evolution of SD-WAN i.e. Software-Defined Wide Area Network. As per analysts, SD-WAN market is predicted to grow 8 times by 2021.

Key drivers of SD-WAN

IoT (Internet of Things) is demanding all-time high visibility and analytics into thousands of devices connected to any network. SD-WAN provides a central management dashboard to all your devices and provides a rich experience.

Security is not anymore appliance-based as most of the applications are moving to cloud. It needs a shift in security measures and also in security products. Today’s companies prefer network architectures that integrate policy, security, and orchestration. SD-WAN can help you to provide consistent and unified security to all your network. Cloud security is also becoming a booming market due to these shifts of applications from on-premise to public clouds.

SD-WAN provides improved application performance and quality of service for remote and branch workers through intelligent path selection or Application Aware Routing. Policy creation and activation were never so easy in the past.

Reduced cost in comparison to MPLS WAN links as SD-WAN allows you to leverage lower-priced broadband and LTE connections. In addition, the hybrid WAN architecture allows you to have a mix of different technologies and leverage the best whatever you need.

At times, some SaaS applications require direct internet access, based on deployments. SD-WAN is really helping in those scenarios as it comes with built-in DIA (direct internet access) features.

SD-WAN Architecture

SD-WAN architecture can be divided into three layers i.e. Infrastructure Layer, Controller Layer, and Application Layer. This architecture is based on standard software-defined networking and SD-WAN is built with similar objectives.

Image Source: Viptela

Infrastructure layer acts as the foundation of SD-WAN architecture. It consists of a physical layer and virtual network devices.

Controller layer consists of a centralized control plane for the entire WAN network and it provides a single centralized view.

Application Layer consists of network services, orchestration tools, and business applications that interact with the controller layer.

In addition to infrastructure, controller and application layer, security is another important design aspect of SD-WAN. In traditional networks, methods for providing security are highly manual and don’t scale. For example, certificates are typically installed manually rather than installed in automation fashion.

One important component of SD-WAN is the communication protocol between the centralized control plane and the distributed data plane. The protocol helps in distribution of policies/routes/keys and certificates across the data plane to enable an agile WAN environment. The protocol can be either be proprietary or use open standards. For example, in Cisco SD-WAN, this is played by the proprietary protocol OMP, which helps in distribution of Keys/Policies/routes between the WAN edge devices and the control plane. The protocol stack uses DTLS as an underlying transport to ensure quick and secure mode of communication and hence can be extended to a very large WAN network.

Business Impact of SD-WAN

In past, there have been many innovations which are cutting-edge in terms of technology but unfortunately, they don’t add great value to the business. It is possible due to higher initial cost to use those technologies or they are far too complex for wider usage.

SD-WAN is not only good in theory but it is making a major transformation in the industry. It is visible from the fact that Cisco is planning to bring SD-WAN to 1-million ISR routers as per recent blog. [Source]

SD-WAN makes the biggest impact on business in terms of operating cost. Enterprises are dependent on MPLS networks for security, system uptime, and various other reasons. SD-WAN brings down this cost by a huge factor and it allows you to use the normal internet or LTE connections with full security. SD-WAN is able to provide centralized configuration for better operational costs. Finally, it also brings network in a state where a network can be orchestrated seamlessly. Zero-touch provisioning and direct cloud connectivity are another major business impacts of SD-WAN.

Industry Landscape

Software-defined networking is not an academic term anymore as it is playing an active role in this major transformation of a wide area network. Centralized controller, unified policies, segregation of data-plane and control-plane are becoming a reality.

SD-WAN industry landscape has observed many acquisitions in the past 12 months. Last year in August 2017, Cisco acquired Viptela on August 1, 2017, for 610 Million$ and later VMware acquired Velocloud on November 2017. As SD-WAN market is growing rapidly, industry landscape may change faster than expected.

As per industry reports, there are thousands of enterprises who have already deployed SD-WAN and this number is growing really fast. As per Gartner report, By 2018 more than 60 percent of enterprises will have deployed direct internet access in the branch offices (up from less than 30 percent 2 years back). SD-WAN is highly recommended for enterprises which are adding remote or branch sites on a regular basis as it is so seamless through SD-WAN to add a new branch to your network.

Criterion SDCloud®

Criterion Networks is a network transformation partner for service providers and large enterprises to accelerate their journey in adopting SD-WAN.

Criterion’s cloud-based solution acceleration platform, Criterion SDCloud® is tailored for customized network transformation use-cases. Criterion SD-WAN Designer offering allows users to plan, design and spin up PoV by using a drag-drop canvas. It allows users to build various SD-WAN topologies instantly and allows users to seamlessly run customer PoC. It is feature-rich and comes with WAN impairment toolset and traffic generator for emulating underlay transports such as MPLS and Internet.

Criterion also provides end to end suite of enablement offerings such as workshops, learning labs and sandboxes to make SD-WAN partners PoV ready.