Are You Keeping Up With SD-WAN?

1. It serves to consolidate a branch network’s functions, including routing and firewall.
2. It supports multiple WAN links and uses network intelligence and policies to direct traffic across those links.
3. It is managed through a cloud-based solution that can be used for centralised policy definition and troubleshooting.

And enterprises consistently cite the same top two reasons they’re considering SD-WAN:

• Reliability – Robust application and branch continuity for branch users and IoT.
• Agility – A network that adapts to and supports business strategy from an infrastructure, management, and cost perspective.

Link Diversity & SD-WAN

While there’s a common understanding that link diversity is important, the actual types of WAN links SD-WAN uses have changed over time.  Initially, Multiprotocol Label Switching (MPLS) and broadband were the most common combination as companies began to gradually accept best-effort networks as a potential WAN while still being reluctant to move away from MPLS entirely.  But with improvements in the ability of SD-WAN to overcome network issues, the increase in bandwidth available on broadband links, and the increased prevalence of cloud and Internet traffic, all-broadband WANs are not uncommon now and are quickly growing in popularity.

Most recently, cellular wireless has become a common WAN link.  Initially used just as a link of last resort or in places with insufficient wired link diversity, wireless is gradually moving into a role as a primary connection.

Changes in Technology & in the Market That are Driving Wireless

Why has wireless become more viable as a WAN link?  From a technology perspective, the amount of bandwidth supported through 4G LTE is substantial, approaching cable and DSL bandwidth levels.  Additionally, the reliability of wireless is improving over time because of technology advancements and carrier build out.

On the business side, carriers are increasingly offering “all-you-can-eat” plans, so customers no longer need to worry about exceeding their data limit, or offering data pooling, where data can be shared across all enterprise locations, decreasing the likelihood of unexpected data charges.

But what really makes wireless an exciting option as a WAN link are the technology changes that are coming.

First, Gigabit LTE is around the corner.  While most users won’t see true gigabit speeds, branches using fixed wireless will have link speeds approaching 400 Mbps.  These are not far in the future hypotheticals.  For example, according to a recent article in RCR Wireless, “Based on a tally provided by Verizon in November, the carrier has fully deployed carrier aggregation in near 2,000 markets and has 4X4 MIMO and 256 QAM available in more than 560 markets. All three technologies are providing Gigabit LTE to users with compatible devices in 560 markets.”

Second, 5G is not that far away.  Trials are currently under way, and by 2020, some large commercial deployments will begin.  5G will offer unprecedented bandwidth, reliability, very low latency connections, and much higher density so that many more people and things can be connected within a geographic area.  Ultimately, this will help support the growth of IoT and more users connecting via wireless. 

The Wireless, Software-Defined Branch

Based on the need for link diversity, it’s obvious why wireless makes sense in the branch.  It may be subject to outages, but it will be subject to different outages than the wired link, giving an additional level of redundancy to ensure branch and application continuity.

But there’s a subtler reason organisations are turning to wireless: It’s becoming key to how they conduct business.  Businesses are expanding their customer edge and travelling to where their customers are, rather than waiting for customers to come to their location.  Retail establishments, restaurants, banking companies, etc. are beginning to reach out to their customers with options such as pop-up locations at concert venues or offices inside of larger stores.  To do this, they need to bring a robust network with them – something that’s only possible with wireless.

Wireless enables businesses to stay connected while retaining all the requirements of a wired network, including reliability, security, quality of service, and application continuity, even when the business itself is not within its traditional terrestrial fixed branch.  By being able to open with one or two wireless connections, organisations still get reliable connectivity with day-1 deployments, and they can venture out further than where only a network connection exists. 

Ultimately, wireless gives organisations complete planning flexibility when deciding how to best engage with customers.  SD-WAN is a trend that is expected to keep evolving over the coming years and will accelerate as wireless technologies such as Gigabit LTE and 5G develop.