SD-WAN underlays BGP network performance

Supercharge Your SD-WAN – Underlays and Why They Matter

As businesses watch their network infrastructure increase in complexity, the deployment of SD-WAN solutions is becoming an increasingly popular choice. Thanks to its versatility, SD-WAN is indeed an optimal choice for many businesses looking to update their IT infrastructure, providing the possibility of dramatically increased bandwidth efficiency, network throughput improvements, and lower costs. Unsurprisingly, the global SD-WAN market is booming. According to recent predictions, it is expected to grow from $1.9 billion in 2020 to $8.4 billion in 2025, representing a compound annual growth rate of 34.5%.

Before the emergence of software-defined wide-area networks, businesses usually had to rely on an MPLS-WAN model for their corporate networks, but these were often rigid and delivered unpredictable levels of performance for sites not adjacent to the hubs for Internet access. Worse, they were far from cloud-friendly in an increasingly Internet-centric world. Given the rise of latency-sensitive applications in the cloud, traditional WAN was simply no longer fit for purpose for many firms.

The Importance of Underlays

For all the promises offered by SD-WAN, the standard of service may vary depending on a few crucial factors. Too often, organizations look to the overlay first – the virtual network solution that manages traffic, enhances cloud connectivity, and essentially delivers all of the benefits that businesses associate with SD-WAN. Even though overlay is undoubtedly important, it pays to prioritize the underlay because it can save a lot of headache, time, and money in the long run. When the physical underlay is neglected, the agility benefits delivered by the SD-WAN overlay cannot perform to their full potential, to the point where all advantages can be lost. As technology keeps growing in complexity, the need for a solid foundation on which to build these innovations increases.

Legacy IT hardware

Many enterprise WANs now fall squarely in the “legacy IT” category and simply aren’t built to handle the kind of traffic flows that most modern businesses have to manage in an efficient manner. The robust on-site corporate networks of the past weren’t built with the cloud and remote access in mind, and as such, they’re actually turning into a major bottleneck. With many enterprises now making use of multi-cloud environments, SD-WAN solutions need to connect physical branches to the cloud, private clouds to data centers, and every digital solution to the internet. Complexity has skyrocketed to such an extent that an SD-WAN solution with a strong underlay is needed to manage it. In a nutshell, keeping the underlay in top shape is instrumental for reaping all the benefits of an SD-WAN solution.

Congestion and Performance Slowdowns

SD-WAN is commonly employed by multinational firms to improve their connection to cloud providers, but these solutions can be hamstrung by the inadequate performance of the underlay network. Today, the internet represents a shared network made up of more than 900,000 individual networks, which means that it is often subject to congestion and performance slowdowns. The complexity of the network and the increasing number of applications call for both efficient prioritizations of traffic and complete visibility.

SD-WAN solutions tunnel logical paths, so they don’t have any real knowledge or control of the underlay. This is especially important given that internet service providers are independent autonomous systems sharing routes with one another. This means your business may be receiving sub-par performance for its SD-WAN tunnels between your branches and peers. Considering that a delay of just a few seconds is enough to frustrate online users and damage productivity, businesses cannot afford to rely on poor network performance.

Border Gateway Protocol

If we take a closer look at the internet, ISPs and cloud providers around the world share routes with one another via the BGP routing protocol. But despite being the internet’s routing protocol of choice, BGP has some serious deficiencies for a cloud-centric world. After all, BGP was developed more than 30 years ago, when the internet was a very different place – a much smaller place.

BGP works well at keeping the internet connected, but it doesn’t always optimize network traffic. With BGP relying on a single metric to select the route between all the autonomous systems (AS) that make up the internet, it often results in organizations dealing with a prolonged round-trip delay (RTD).

Improve the performance of your SD-WAN

There is a vast array of options to choose from, and the right choice is very much a case-by-case situation, depending on the needs of the business. Regardless of that, businesses just need to make sure their SD-WAN won’t be hampered by internet peering problems or limited ISP choice. Regulatory issues add to the challenge, as does the fact that many vendors continue to have a limited understanding of how SD-WAN connects to the cloud. Getting your underlay network right and keeping it in top shape as your IT infrastructure evolves is essential.

This is where working with a network solutions provider that understands the technology, its importance, and your needs can add real value to your business and help you get the most out of your SD-WAN solution.

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