Why SD-WAN needs to be de-hyped

7 September 2020

SD-WAN has become increasingly popular in recent years, as it quickly becomes the new ‘thing’ that everyone wants and is spending big money on. The traditional Wide Area Network (WAN) helped companies work on a national and an international scale, however, it did have limits on how companies could scale and remain agile. The next solution has been to add SD-WAN technology solution on top of a network to increase efficiency, agility and security. 

However, while there are benefits to SD-WAN, there has been significant hype on the appropriation of the technology for UK based companies. The issue is that this hype has led decision-makers to be misled, spending thousands on technology that actually isn’t going to have much business benefit at all. 

By debunking the hype and cutting through all the marketing madness, IT professionals can make correct decisions when it comes to their network. 

SD-WAN: The definition 

Software-Defined Wide Area Network (SD-WAN) is a shift in the way that a WAN is managed and deployed. A WAN was used to connect different branches to a central network or connect data centres that are far apart and required traditional (not necessarily legacy) network technologies like MPLS. However, SD-WAN uses the internet or private cloud networks and is deployed as an overlay technology to an existing topology. 

Integrated into a multicloud strategy, SD-WAN has been tipped to improve connectivity and boost security thanks to its scalability and centralised management for both private and public cloud. As a result, business leaders and decision-makers can have far better visibility across their network and understand what is going on in real-time, manage the international network at speed and also give them the power to upgrade and enhance without any changes to the infrastructure.

This, of course, sounds highly desirable for business leaders, however, it does look a little different when you look under the bonnet. 

SD-WAN: The truth

As technology advances at such a pace, advances in networking are inevitable and something that is exciting and important. However, what comes with change also comes with slight misunderstanding and opportunities arise to be misled by large scale corporations and vendors. Many vendors have bundled together existing technologies into a brand spanking new package labelled SD-WAN with a slick graphical user interface (GUI) and a (potentially) hefty price tag to accompany it. 

The SD-WAN solution has automated certain technologies such as PfR (Performance Routing), NBAR (Network-Based Application Recognition) for application awareness, traditional 3/4 Firewall, IP-SLA, object tracking and per-packet/session load-balancing for good measure – this is the Cisco nomenclature, however, you can match these technologies to other vendors. Of course, automation of technologies is important but in this case, it’s causing companies to completely ditch their existing infrastructures which are imperatively used as a foundation to their business and as such, eliminates all back-up support systems. At a time where the internet is already vulnerable, it opens up many holes. 

Relying solely on the internet to run a business is a bold move in the current climate. SD-WAN has been formulated in the USA, and works very well due to its geographic size and dispersion as well as the associated technologies to cater for that size – MPLS is relatively expensive, internet (any transport technology) a little less expensive. Moving it over to the UK with the same expectation of deployment, speed of adoption and smooth running of service across the network is quite a naive standpoint. 4G coverage in the UK is still relatively low and consequently won’t provide the seamless integration required to make SD-WAN effective in cases such as companies offering real-time services – voice services or similar – who can’t afford to have major latency or jitter. 

SD-WAN has offered a few different opportunities to help improve business efficiency and efficacy – but for UK companies ditching existing infrastructure in favour of SD-WAN, that could be a catastrophic business decision. It’s important that companies don’t fall foul to marketing hype and buy into something that won’t be effective. By providing the bigger picture everyone can let their business requirements define their solution needs, rather than forcing a solution because of marketing hype. 

Personal side note: I have only seen 2 use cases in the UK that I would deem suitable for SD-WAN, the rest have bought into the marketing. One particular use case was using SD-WAN with a single internet connection per site… for 3 sites… No resilience, IP-SLA cannot work, PfR cannot work, load-balancing cannot work. Pretty much pointless, apart from maybe the zero-touch deployment and centralised security policy.

cloud connectivity
cloud infrastructure
Neil Briscoe