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SD-WAN: Today’s Networking Technology


The following article is from CIOReview

A few decades ago, Sun Microsystems coinedthe phrase "The Network Is the Computer" to define its product strategy. In today's world of complex applications, sophisticated data analytics, pervasive use of multimedia and a widely dispersed workforce,the network is increasingly the lifeblood of any corporation.

Traditionally, most corporations, including my own,have usedMultiprotocol Label Switching (MPLS)-based wide area network (WAN) services to move vast quantities of data. A distinct advantage of MPLS has been its high reliability ensured via service level agreements (SLA) with service providers. Conversely, high bandwidth costs have been its biggest limitation, driving up operating expenses in the data-hungry world in which most companies live. MPLS networks are also notoriously slow to provision or upgrade.Initial setupscan take months and a simple bandwidth upgrade can be a weeks-long process.

Companies have long sought to address these hurdles by selectively migrating services to the public Internet, which is significantly cheaper and quicker to upgrade. However, the Internet still suffers from performance inconsistency, despite rapid improvements over the past decade. The upshot is that many companies have been living in a hybrid world, with mission-critical traffic being sent via MPLS and the rest via cheaper Internet services. This has created additional overhead since the appropriate routing of traffic becomes a manual process handled by network programmers and administrators. The quest to solve this problem of balance between performance and cost is leading many corporations to turn tosoftware-defined (SD)WAN technology.

In basic terms, SD-WAN is a software service that enables enterprises to dynamically route traffic across a hybrid network environment. The technology is rapidly gaining wide adoption. At ECMC Group, we are adopting SD-WAN capabilities as part of ourstrategy to migrateour entire application portfolio to the cloud, including Microsoft Office, custom-built transaction systems, third-party software as a service (SaaS) solutions as well as data warehousing and analytics platforms. In addition, our company relies heavily on virtual communication platforms for voice and video. Collectively, these requirements have underscored the criticality of reliable and cost-effective WAN services with minimal administrative overhead.

We see several key benefits from moving to this technology.

Performance Flexibility: SD-WAN solutions enable a hybrid WAN to react to changing network conditions automatically, a characteristic that provides unprecedented flexibility. Its routing appliances and algorithms evaluate the different transport options and distribute traffic accordingly. For instance, traffic with higher quality of service requirements will be routed via MPLS, while others leverage the Internet, providing higher bandwidth at much lower costs.

Lower Cost: This benefit is a natural offshoot of the above. With SD-WAN, we anticipate being able to rely more on less expensive broadband circuits versus our private links. This offers us the freedom to invest in the higher capacity broadband links and minimize the size of our expensive MPLS circuits. The dynamic routing features of SD-WAN solutions also mean that network capacity can match increases in demand without the need to invest in additional WAN infrastructure.

Security: While the inherent security limitations of the Internet are well understood, SD-WAN solutions compensate for this deficiency by using standards-based encryption to provide connectivity over any type of transport, thus establishing its own secure network.Any new SD‐WAN device has to first beauthenticated to this network and receive its assigned policy before being granted access. Policies can allow sensitive traffic to have its own encryption keys and be isolated from the rest.

Simplified Administration: Manually configuring a hybrid WAN is challenging.Routing protocols typically stay with the single best path between two points and don't react to changing conditions in the network such as packet loss, congestion, etc.Furthermore, any changes in traffic patterns must be accommodated by manually changing configurations. This drives administrative overhead from the IT staff. The SD-WAN model allows the routing logic to be pre-configured, but on an ongoing basis, relies on the software to evaluate and direct network traffic in real-time;thereby,limiting the need for further manual intervention.

It is worth noting that while implementation-ready, SD-WAN is continuing to evolve in its maturity. Coupled with performance improvements on the public Internet, it is possible that companies will completely eliminate dependency on private links in the very near future.

A second point of note is the implication for IT talent. Configuring SD-WANs will require IT staff to be more strategic and less tactical in their approach, much like a city planner, ensuring that the model defined at the outset can fully leverage the autonomous capabilities of the network on an ongoing basis.

SD-WAN is quickly becoming the preferred networking solution within corporations and, therefore, the conduit to efficient and effective systems—an exciting development for organizations and IT professionals as we look to enhance our technology environments now and into the future.