SD-WAN Monitoring: The Context Conundrum

by Christine Cignoli on December 26, 2017

Software-defined architecture is the next big thing for networks, allowing companies to shift away from costly, inflexible hardware to more agile and adaptable solutions. Consider software-defined wide area networks (SD-WAN), which some experts see as the natural replacement of multi-protocol label-switching (MPLS) solutions currently in use.

There’s some justification for this position, since SD-WAN offers reduced costs and greater flexibility. But software-defined solutions come with their own issues, such as quality of service (QoS) enforcement challenges and lack of application monitoring. How do companies considering the switch to SD-WAN ensure they’re armed with both complete context and total control?

There's Strength in Software

While the software-defined market has gone through its share of hype, most solutions actually on the market have come out the other side relatively unscathed. SD-WAN is among them; as noted by Biz Tech Magazine, this networking approach “offers both financial and operational benefits to organizations.”

These benefits include:

• Companies can add or remove bandwidth without disrupting network operations, since SD-WAN routers can combine multiple connections and all connections are defined by software protocols instead of hardware switches.
• Traffic can be encrypted on the move, and administrators can segment traffic to contain a potential breach. Transparency also gets better thanks to available application monitoring solutions, which offer real-time activity reports.
• Companies with multiple branch offices and networks often benefit from SD-WAN implementation, since these solutions make it possible to enforce business-wide QoS and security policies, effectively governing disparate networks under a single framework.
• SD-WAN networks also help empower the next iteration of IT problem-solving and monitoring: Automation. By linking top-level security, provisioning and routing rules under a reliable SD-WAN, it’s possible for companies to implement automated reporting and detection tools. This reduces the amount of repetitive work required by IT admins while simultaneously increasing accuracy.
• MPLS solutions are expensive, since they rely on pricey hardware and companies must budget for regular maintenance along with eventual replacement. SD-WAN offerings leverage public internet connections at the edge of corporate networks and control them using software, in turn reducing both upfront investment costs and ongoing obligations.
• While MPLS offerings typically include backup and disaster recovery solutions, the inherent multiplicity of SD-WAN connections makes it far more difficult for hackers or disasters to sideline software-defined solutions.

SD-WAN Technology Challenges

While SD-WAN offers measurable benefits over traditional MPLS solutions, it’s not a perfect technology. Common challenges of software-defined networks include:

QoS Management

SD-WAN solutions are often used for VoIP and video calls since access to broad bandwidth pipelines provides reliable connections and reasonable call quality. The problem? Because SD-WAN is an edge technology, companies lack granular control over QoS. While some providers offer guaranteed QoS, what they really mean is selecting the best network path for calls—if all are equally bad, calls will still experience lag and jitter.

Existing Implementations

New technologies often get pegged to replace existing solutions, and that’s certainly the case for SD-WAN for MPLS. But the public-facing nature of WAN makes it a bad idea to toss existing MPLS immediately; this could hamper overall SD-WAN adoption while MPLS architecture is still working well.

WAN Optimization

One key benefit of WAN solutions is the optimization of traffic flows, typically via compression. But high-density, high-security traffic offers little room for compression, making the case for SD-WAN difficult when existing solutions still perform adequately.

Service-Level Agreements

Another challenge for SD-WAN adoption is pre-existing SLAs. If companies have already made agreements with MPLS or other network service providers, it may be cost prohibitive to break these agreements and implement software-defined solutions.

Application Context

SD-WANs are ideal for managing network and application loads, but provide virtually no context about user interaction with these applications without additional application monitoring. It’s a birds-eye view, ideal for getting the big picture but not so useful when it comes to per-user data.

Improving SD-WAN

Put simply, SD-WANs lack context. This isn’t surprising, since these networks are designed to offer broad, unifying strokes at a cheaper cost than MPLS. The problem? With user experience—and therefore overall productivity—now tied to the performance and security of mobile and web-based applications, SD-WAN networks that provide connections with no context can only go so far.

Ideally, companies need SD-WAN monitoring solutions capable of contextualizing application performance by monitoring both applications and their specific network paths. By combining better routing with real-time observation of end-user interactions, it’s possible to see exactly where software-defined solutions are delivering on their promise of ROI and where more work is required.

SD-WANs offer marked improvement over MPLS networks in many areas, but they lack the ability to guarantee QoS and drill-down into the user experience—critical aspects of the digital-first user environment. By pairing software-defined technologies with SaaS-driven network and application monitoring platforms, however, it’s possible to tap the benefits of SD-WAN without losing critical context.

Request a trial of AppNeta if you’re implementing SD-WAN and need application monitoring.