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Embracing the future with SD WAN

Embracing the future with SD WAN
November 23, 2016

Challenge and change

With a series of changes sweeping through the business landscape, the cloud is rapidly transforming into a major revolutionary force. In response, organizations are proactively adopting the cloud, driven by a plethora of benefits – scale, scope, economic advantages, speed, agility, infinite elasticity, flexibility, and innovation.

Additionally, most enterprises have either moved their data centers to the cloud or are planning to make the change because of the proliferation of apps, reduced costs, and dynamic traffic transit.

However, there are certain issues that firms must address before they can initiate a large-scale migration:

How should the enterprise network be reengineered so that it offers more scalability and reliability, and a cloud-ready approach? How does one provision on-demand network bandwidth for users enabling hassle-free connectivity to all applications and workloads?

Enterprise branch networks have expanded because of the global nature of businesses today. Branch offices are critical as a substantial portion of business-employee-customer interaction takes place at these locations.


It is no wonder then that branches are the focus of the enterprise network infrastructure. The need for real-time services and a seamless access to applications at a branch level have caused a bandwidth crunch for these firms. However, wide area networking (WAN) budgets have remained flat. Further MPLS WAN pushes up costs and impedes process simplification.

It is, therefore, a financial challenge for CXOs to ensure a seamless user experience as well as application availability at a reduced cost.

Software-defined WAN (SD WAN) can be thought of as a solution. It is a fast-growing space with a large ecosystem of vendors. Start-ups such as Viptela, Citrix, and VeloCloud and industry leaders such as Cisco, Brocade, and AT&T consider this as a leap forward in terms of WAN optimization and modernization. SD WAN permits traffic control, quality of service (QoS), security, and WAN acceleration over less-expensive DSL, business broadband, cellular, or other connections.

Enterprises can leverage the solution to ensure that there is a smooth offloading of traffic from expensive MPLS WAN connections to cheaper Internet transport options, thus improving ROI.

Therefore, the maintenance of a hybrid WAN architecture (with MPLS WAN integration) can enable critical transactions to traverse effectively and efficiently over the private IP network through the Internet.

Way forward – CNLs & Colocation Services for the future

SD WAN has, however, seen limited adoption and full-scale deployment. This is not without reason. First, the benefits of the WAN network are restricted in a traditional meshed network architecture. Second, the availability of a single ISP with last-mile availability for all branches and handshaking with the public cloud players poses risks to crafting a global WAN network architecture that can fully leverage the benefits of transport independence while enhancing user experience. Can the enterprise have a truly distributed architecture with geo-local connectivity provided as an SD WAN point of presence (POP)?

The concepts of carrier-neutral locations (CNLs) and colocation services/networking are relevant here. With an extension of an enterprise network into a CNL provider, enterprises can securely and reliably connect to the network and cloud service providers using off-the-shelf networking and express routes.

Thus, CNLs not only ensure diversity and flexibility, they also allow enterprises to leverage colocation services untangle themselves from any one service provider (ISP). Additionally, enterprises can virtually outsource their data centers to CNL data providers. The architecture, while unleashing the potential of CNLs, provides points of interconnection for enterprises via colocation services to connect directly to hybrid, private, and multi-cloud environments.

This is achieved by the creation of an overlay network that enables each branch location to leverage the most desirable access routes to the cloud. The offering improves service performance by taking branch offices closer to the data centers while ensuring the best speed, reliability, and quality.

Organizations should evaluate the WAN network in detail because of the growing importance of the branch office and the need for seamless access to applications and services through the cloud.

The big question, then is: Can enterprises overhaul their network connectivity using SD WAN? Careful planning and robust implementation could lead to the tapping of SD WAN’s potential, playing a central role in shaping the next-generation enterprise — which is experience-centric and interconnected.