Rolling out SD-WAN? Here’s how to quantify ROI & business value

How can you be sure you are getting the most ROI for your network transformation and modernization projects with SD-WAN?

Test and you shall perceive.

Validation is key to ensuring SD-WAN services meet your expectations of cost savings in network operation, faster deployment, efficient load balancing, and increased performance. This is also how the IT department and SD-WAN champions within the business can demonstrate its actual value to the business.


Typically, organizations make the switch to SD-WAN for four reasons:

  1. Wide-area network (WAN) services based on multi-protocol label switching (MPLS) are expensive and difficult to configure and change. In comparison, deploying SD-WAN allows connectivity over the public Internet instead of dedicated links and load balances across multiple WAN infrastructures like MPLS, LTE, or broadband services. Thus, deploying SD-WAN allows the MPLS based WAN to be utilised in a more cost-effective manner.
  2. It allows for centralized management, providing a reduction in administration and IT management costs.
  3. It offers increased reliability, using intelligent routing to select the most efficient traffic flow path based on Quality of Experience (QoE) metrics.
  4. It allows for more efficient transport of SaaS-based applications such as Google Cloud or Microsoft services.

But “more cost-effective”, “better reliability”, “simpler management” and “more efficient” are only measurable objectives if you can quantify them. ROI can be measured if you determine and quantify what things were like before and after the implementation, or if you measure current state and then test again after you take steps to improve from here.

Each time you deploy an SD-WAN solution or expand your network of SD-WAN gateways, you can conduct pre-deployment, virtual network testing so you know for sure what the impacts will be, catch any issues and make any necessary adjustments before you go live.

Real World Modeling of Network Change for Peace of Mind

It is possible to validate Network, Applications or Security changes across the entire stack – including networking protocols, services, applications, and cybersecurity – to deliver meaningful test results and relevant, actionable insights.

To do so, in advance of a go-live date for any kind of network change, you must conduct “real world” testing that replicates your live network in action. It’s imperative to test with the most realistic application workloads, traffic mixes, dynamic payloads, threats, and attack vectors included.

Whether you are proof of production concepts, planning, valid designs, or continuously into testing, test traffic profiles should live network workloads. The ability to replicate the network in action means you can ensure performance, functionality, quality of experience (QoE), and security efficacy.


3 Key Aspects of SD-WAN Performance Testing

1. Quantify pre- and post-deployment service levels

It is essential for Enterprises to undertake pre-deployment benchmark testing of the existing WAN performance, to test before your go-live date, and to conduct post-deployment testing following the adoption of SD-WAN.

Choose test solutions that can emulate a fully scaled network, generate real-life workloads, and measure relevant traffic characteristics.

You may be saving money with SD-WAN, but that cannot be your only driver. Cost saving is great, so long as it doesn’t affect services.

The goal is to quantify and measure your service level, so you can assess whether SD-WAN is providing the same service level, if not better.

2. Validate routing capability

The WAN gateway needs to incorporate routing intelligence in the overlay network for site-to-site communication to happen over MPLS tunnels.

That is why we designed our flagship testing solution, Keysight IxNetwork, to test Layer 2/3 infrastructure, by emulating protocols and generating traffic at the high scale required to validate the routing capability of SD-WAN networks.

3. Performance Validation at the Application Layer

To create realistic test scenarios, choose a test solution like Keysight IxLoad, which works at the application layer to deliver comprehensive performance validation for user QoE over SD-WAN services.

What you need is a test that emulates enterprise applications at scale behind the branch offices or across SD-WAN networks. Emulations must include protocols for web, video, voice, storage, VPN, wireless, infrastructure, and encapsulation/security applications.

Tangible Results

Network change is inevitable as needs change, businesses grow and technologies advance. Every change has desired outcomes and in order to measure against those objectives, you need to be able to quantify the results. Network testing and visibility is necessary to provide those quantifiable results and should be a part of the planning process rather than an afterthought. Tests scheduled at critical junctures of any change project can help to ensure the desired outcomes.

In the case of SD-WAN, testing helps you identify gaps in your network strategy that may otherwise prevent you from achieving the desired ROI on your SD-WAN deployments so you can take corrective action.

Building in testing contributes strongly to professional risk management practices and provides the peace of mind that comes with being able to anticipate the results as well as the ability to provide documentation using quantified results.

With tangible information such as time and dollars saved, capacity achieved and speed improvements, you can report on the value SD-WAN has added to the business in real terms, relevant to the bottom line.

About the Author

Sawan Singh is a Solution Architect and Solution Consulting Engineer from the Network Applications and Solutions team at Keysight Technologies. Keysight delivers advanced design and validation solutions that help accelerate innovation to connect and secure the world – including network performance optimization and visibility in enterprise, public sector, service provider and cloud environments. Visit or CONTACT US for more info.

[1] GlobalData 2020


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