The WAN used to be controlled by hardware switches and physical cabling. Although this is still the case in many companies, a number of businesses have set up something entirely new—a fully programmable WAN. This is an upheaval. It brings many changes to the discipline of information technology, such as:
- How architects design their networks
- How companies procure network hardware
- How administrators propagate changes to their networks
Most of these changes are for the better. SDx and other forms of advanced networking make it faster and easier to deploy networks to more places, and tend to be cheaper than alternatives such as MPLS. Furthermore, it achieves these benefits without a drastic drop in quality. Like any new technology, however, the various incarnations of SDx are not without their challenges. What do these new hurdles look like, and how can businesses climb over them?
Weighing the Benefits of SDx
The benefits of software-defined networking hit on three big bullet points:
- Lower costs
- Faster implementation
- Improved reliability
Quantifying these benefits can be a nebulous exercise. Mileage will vary based on the size of a company, its need for remote workers, and the extent to which it’s already using the cloud. The right kind of business will benefit greatly in terms of cost—according to Gartner, a company with a 250-branch traditional WAN will save $832,500 over three years by switching to SD-WAN.
If SD-WAN is so much cheaper than traditional WAN, why hasn’t everyone switched over already? Part of the problem is that traditional WAN represents a huge sunk cost in terms of infrastructure. Many organizations use custom ASICs as part of their network management solution.
These are expensive, and they last a long time—only in recent years have generic chipsets gained parity with customized solutions. The other side of the coin, however, is that once these old management solutions finally age into obsolescence, it will be trivial to replace them with software-defined solutions. This is how SDx is changing procurement, by the way. It’s replacing yet another piece of dedicated physical infrastructure with something lightweight or virtual.
As opposed to customized physical infrastructure, most SD-WAN solutions are available as virtual machines, or as lightweight appliances. Implementing these solutions can be as simple as turning them on. Once SDx is implemented, however, it can be a challenge to meet that third critical goal of reliability.
New Challenges in Software-Defined Networking
SDx is promising, analytically. Traditional WAN and commercially available internet connections usually just provide a monthly bandwidth usage report, with little else to give context or allow administrators to tweak their setup. Next-generation WAN promises more, but it’s a long way from being totally useful.
Some SD-WAN technologies, for example, can provide real-time intelligence on multiple linked networks at a speed that encompasses 500,000 metrics per second. These metrics tend to be skewed towards optimized routing decisions, however, which means that built-in SD-WAN analytics have a big blind spot: applications.
SD-WAN applications give administrators the ability to see when connections are performing poorly, but it can’t give you a window into the health of your applications in the cloud. Therefore, it’s possible for poor application performance to be lost in the noise.
AppNeta completes the SDx monitoring package by adding application context to network monitoring. Our solution reaches across the wire to determine the health of applications in the core, in the cloud, and at remote sites, eliminating guesswork and letting administrators resolve issues proactively.