We get it now. The cloud is a thing. It’s a great thing and it’s revolutionising everything from how we do business, to how we listen to music, even to how we heat our homes, but there comes a point when the analogies and the ability to extol its benefits dries up.
The beauty of technology though is that it never stands still, and just as the drought sets in, along comes something new and exciting to explore. SD-WAN or Software Defined-Wide Area Network is the latest innovation to disrupt proceedings and help deliver the benefits of cloud. It’s not just another acronym to add to the collection either. Although deployed by only around 1 per cent of businesses worldwide, American marketing research firm Gartner predicted last year that by the end of 2019, an astonishing 30 per cent of enterprises will deploy SD-WAN technology in their branches. So, what is it?
Taking its lead from WAN optimisation, a technology derived to accumulate an understanding of private WAN connections and then optimise them for recurring traffic patterns, SD-WAN goes further by dynamically selecting a more cost-efficient assortment of public Internet connections and private links. It achieves this by allowing a network manager to combine different connections and configure them to behave like a network by using traffic engineering and path selection. Applications are no longer at the mercy of standardised bandwidth, rather they select the connection most able to allow it to perform its duties. As a WAN alternative, it is clear to see why it is threatening the throne of traditional MPLS, but let’s make it clearer still. What are the headline features of SD-WAN that make it so compelling? And will it really mean an end to MPLS?
Proponents of traditional MPLS WANs have always pointed to the unmatched security it offers. However, revelations from former CIA operative Edward Snowden have dented that argument. The seeming ease with which the US government was able to tap into and monitor networks brought home the fact that other agencies or individuals, with even less honourable intentions, could also do the same. SD-WAN communication is usually secured using IPsec, which works by validating and encrypting each IP packet of a communication session. If not IPsec, then something else such as TLS, but whatever is used, encryption comes as a standard and it is at least as secure as MPLS.
The Quality of Service is unmatched
SD-WAN technology delivers QoS by accommodating application requirements. It recognises mission-critical applications and provides them with bandwidth priority. By aggregating connections, it deploys dynamic path selection and can send an application on a faster link, or by dividing an application between two paths getting it to its destination quicker and improving its overall performance.
Regular applications are optimised
Another feature which adds to the rapidity of SD-WANs is their ability to cache and store recently accessed information. Speed is thus ramped up by the requisite information sitting ready in the network and primed for delivery.
With various delivery paths available for applications to travel through, outages can be mitigated by simply switching over to another, working link. The switch is done automatically meaning the threat of network downtime is diminished to almost zero.
Overall management is simplified
GUIs (Graphical User Interface) are standard with SD-WAN meaning networks can be controlled and configured using icons rather than reams of complex, technical text. Appliances can be configured based on an application’s requirements, side-stepping obstacles presented by basic hardware. Also, as discussed earlier, automatic path selection means an end to needing technical expertise to switch connections in the event of an outage.
MPLS circuits are expensive to install and expensive to scale, especially when the bandwidth they can provide is taken into consideration. By switching to SD-WAN, companies can leverage lower cost and better connectivity by transferring their traffic flows onto greatly improved, public broadband and the Internet.
So, are MPLS networks set to become redundant?
The short answer to this is no. Well, not yet anyway. The reason MPLS has stood the test of time, and why most businesses aren’t thinking about switching any time soon, is that it offers certain assurances. SD-WAN operates over the internet and despite utilising several connections, performance and availability can never be guaranteed.
IT Managers are also unable to ignore the fact that practically all MPLS services include multiple levels of QoS, meaning that users can specify minimum thresholds for different types of traffic when it comes to jitter, packet loss and latency. So, for example, the MPLS network treats real-time latency-sensitive traffic, like video and voice, preferentially over less-sensitive traffic.
In terms of cost, though cheaper to install, scale and operate, IT Managers will need to weigh up whether the savings are compelling enough to make a wholesale changeover to SD-WAN from MPLS. Though businesses can save as much as 40 per cent annually, this is not an average figure, and in some cases the savings can drop to as little as 5 per cent. If the only factor being explored is a financial one, some managers may not find the margins compelling enough.
SD-WAN technology is still at a nascent stage which explains why only a few swashbuckling businesses are going all in. It’s more prolific uptake is likely to come in the form of hybrid WANs where companies deploy both MPLS and SD-WAN infrastructures, though this would surely point to MPLS being eventually phased out as SD-WAN becomes more sophisticated and reliable.
One thing most can agree on though is that SD-WAN is no passing fad. It might take a bit of time to comprehensively usurp MPLS as an industry standard (ten years by the calculations of some) but it represents a new dawn in networking. Keep your eye on this new kid on the block, sooner or later it’ll most likely be ruling it.
Will Kennedy, Sales and Marketing Director, Solar Communications
Image Credit: TZIDO SUN / Shutterstock