Choosing the Right 5G/LTE Gateway for SD-WAN

One of the most essential functions of any SD-WAN solution is its ability to maintain optimal connections to critical applications and resources even when primary internet connections fail or become unreliable. Public internet connections over fixed lines like cable or DSL can be unreliable, creating a bottleneck and single choke point in case of an outage. That’s why many SD-WAN solutions provide LTE and 5G failover options to help maintain optimal user experience. Cellular or wireless SD-WAN options provide faster and more flexible broadband at the enterprise edge, helping ensure reliable, high-performance connectivity while keeping costs far below those of MPLS and other interconnect provider options.

SD-WAN gateways should enable flexible deployment with optimal cellular reception

The internet is now part of the corporate network, especially for remote locations and users. A growing number of business-critical devices and applications rely on the public internet for 24/7 connectivity, including medical devices, connection-sensitive OT devices, and ATM systems. They must have optimal reception, or reliability suffers. Fortunately, cellular gateways are designed to provide gigabit and multigigabit options to connect critical networks and devices, whether as a primary connection source in some geographical locations or as a critical backup.

The challenge isn’t so much that SD-WAN solutions lack cellular or wireless connectivity options. It’s the configuration of the device that can be the problem. Embedding a cellular gateway SIM directly into an SD-WAN platform can lead to limited coverage. These edge devices are often deployed in discrete locations where cellular reception can suffer (such as a basement or closet). An SD-WAN device running in a back room with poor reception, for example, may not be able to provide access to critical devices or users at the front of a store or office. Cellular reception can also be affected by factors such as branch geolocation, building materials (concrete or steel walls), technologies such as microwaves that can disrupt service, and large or oddly shaped office or retail spaces that can create coverage gaps. Because of these and similar issues, many businesses of all sizes are simply unable to effectively deploy 5G or LTE gateways to ensure fast, inexpensive, and flexible broadband connectivity at the branch edge.

Instead, organizations should be able to connect separated cellular modems to their SD-WAN edge devices via an ethernet cable while running the gateway and antennae to a window, the roof, outside, etc. This enables access points to be deployed wherever they are needed. While such a strategy may seem intuitive, what’s surprising is the number of solutions that cannot do this to ensure maximum reception reliability and flexibility.

SD-WAN gateways should future-proof organizations against cellular evolution

Another common issue is not being able to support changes to connectivity without ripping and replacing existing technology. Cellular is evolving rapidly—certainly far faster than the expected lifespan of most devices. So, while a user may begin using LTE or Sub 6Ghz cellular in their SD-WAN fabric, they may need to move to mmWave once it’s available at their branch location. Doing so should not be affected by the limitations of their existing hardware, preventing them from rapidly implementing digital innovations due to inflexible hardware.

With hardwired solutions, the entire device—compute, memory, etc.—needs to be refreshed to support whatever’s next. But a gateway modem can be upgraded without refreshing the entire edge device. A separate gateway enables IT teams to make fast, zero-touch upgrades without the cost and overhead of replacing the entire edge platform, helping to protect original edge device investments.  

Gateways should provide out-of-band management (OBM) and high availability at a lower cost

Out-of-band management (OBM) allows administrators to remotely control and manage critical IT assets and network equipment outside of the traditional provider network. It does this by creating a secure connection through a secondary interface different from the primary network connection. This alternate connectivity route allows administrators to remotely control devices and networks even during an infrastructure failure.

An effective SD-WAN gateway should offer dedicated cloud management dashboards that include simple OBM capabilities. In addition, these gateways should also provide support for multiple OBM console connections to numerous serial cables and adapters—a nice feature if there are a variety of consoles that require remote access. OBM features provide ease-of-use benefits that can be especially valuable in times of high stress, such as critical network infrastructure outages.

Gateways should provide flexible management options to address multiple deployment scenarios

The edge is a very dynamic space, and cellular technology is advancing fast. LTE already provides multigigabit speeds at the enterprise edge, Sub 6Ghz has already rolled out, and mmWave is on the way. In addition to supporting different flavors of cellular broadband, many companies also need to leverage these technologies in various ways. Because of this, gateways need to provide a range of management options. Highly technical security teams should be able to deploy, manage and monitor their gateways using a customizable dashboard. Networking and security teams may prefer an integrated management console. And leaner IT teams who want simple-yet-powerful management may prefer a cloud-based dashboard that offers critical capabilities such as OBM.

Not all SD-WAN solutions are alike

Although many SD-WAN devices may look similar, it’s important to remember that all-in-one solutions can hinder user experience by tying cellular reception to the edge device location. Standalone gateways with flexible cellular modules that can be deployed anywhere in the environment provide more flexibility and service reliability. Separate cellular modems allow IT to place them where reception is best while ensuring painless technology upgrades. In addition, flexible management options, OBM, and high availability mean that the total cost of ownership is reduced while the device’s lifespan is significantly increased. Choosing the right device not only simplifies deployment and management concerns now but ensures that your investment is returning dividends for years to come.

Take a security-driven networking approach to improve user experience and simplify operations at the WAN edge with Fortinet Secure SD-WAN.