The adoption of SD-WANs continues to skyrocket. ZK Research forecasts the market for SD-WAN infrastructure and services will grow at almost 70% CAGR between now and 2022.
Why such strong adoption? For most businesses, the WAN is long overdue for an upgrade as the current architecture has been in place for well over three decades. If done right, SD-WANs can be one of the rare IT initiatives that can lower costs, improve worker productivity and simplify IT operations.
It’s important to note the caveat I made with “if done right” as deployment success depends on ensuring the right architecture, and this can vary widely from company to company. As is the case with most technologies, one size definitely does not fit all with SD-WANs. One of the biggest debates in SD-WANs is the use of Internet-based broadband versus a private network. For small businesses that have regional networks, broadband is likely sufficient. Traffic volumes are typically light and the distance that network packets have to travel is short so the quality of experience for applications, even real-time ones like voice and video, will likely remain high.
It’s a different story though for large, distributed organizations, particularly global ones. The low price of consumer broadband makes it attractive but there are some risks of using the public Internet as the backbone of a global organization. The first and most obvious risk is quality, particularly for real-time and bandwidth-intensive applications. Users may not notice if the experience of best effort applications, such as e-mail, is impacted but certainly will if voice calls or dropped or if video sessions are choppy as the conversations become unintelligible.
The SD-WAN industry is still in its infancy and there are few best practices regarding the use of broadband for a business network. Below are the top concerns that network professionals should be aware of when looking at the broadband versus private network decision.
- Variable circuit sizes. Broadband speeds can vary widely from under 1 MB to multi-gigabit. There is also variability in the type of broadband where fiber speeds greatly exceed any kind of copper connectivity. Wireless services appear attractive but often have high latency and are metered services. Also, with most broadband services, the network upload and download speeds are different.
- Inconsistent bandwidth speeds. Some broadband types, like cable and cellular services, are shared networks. This means if a business happens to be one of only a few entities connected in that area, the speed will likely be great, often exceeding the subscribed rate. However, if the area is oversubscribed, the speed can be significantly lower that what is expected. Adding to the complexity is that time of day can play a role as well as in highly dense areas, consumer usage can impact business users during peak periods.
- Network specific issues. Various broadband types have different characteristics, which can cause application issues. For example, 4G services can suffer high packet loss, where Ethernet can often drop packets. It’s important that the right types of network optimization be applied
- Security concerns. The use of public cloud services brings with it a number of new threats. The old model of placing a big firewall at a single ingress/egress point no longer works as every branch and mobile worker creates backdoors. The network needs to become a sensor for unusual activity that could indicate a threat.
Legacy, private networks, such as MPLS, have the luxury of being very consistent from location to location and are considered to be secure. Also, the ability to use class of service (CoS) for proper application categorization ensures optimal application performance. However, MPLS can be very expensive and inflexible, which is why many businesses are investigating SD-WAN.
SD-WANs, on the other hand, bring a number of new challenges that need to be overcome. Historically, businesses may have been able to turn to a managed service provider (MSP) to help offset much of the complexity of deployment. MSPs may be able to help with factors like network configuration and broadband selection but won’t be able to address issues such as Internet latency that can lead to poor performance.
What’s needed today is a new kind of managed service provider known as a converged MSP. These service providers can deliver all of the value of a traditional MSP but build their own technology stack and global backbone. Think of a converged MSP as a hybrid of a traditional service provider and a managed service provider giving customers the “best of both worlds” as they are a single vendor that has the integration expertise of an MSP but then has the control an inherent security of a service provider that owns its own network. This will also lead to better costs, faster evolution, and innovation.
SD-WANs are fundamentally different than legacy WANs. Doesn’t it stand to reason that SD-WAN vendors need to look a lot different than service providers did a decade ago?