Enterprises often use cellular for WAN failover because of performance, flexibility, and cost
How would your business fare if your internet went down for hours? Days?
For most businesses in the 21st century the answer is “not very well.”
Businesses rely on internet access for everything from processing credit card payments to accessing email and apps that are hosted in the cloud. According to one estimate, internet downtime costs at least $500 per MINUTE, on average. Most wired internet providers guarantee 99.99% uptime, which sounds pretty good. But 99.99% uptime means on average four minutes per month of downtime, or $2,000 cost to the business from the internet being down every month.
Downtime, however, does not come in once a month four-minute increments. You might go a few years with no downtime, until there is an outage. The typical outage lasts 90 minutes, costing the typical business $45,000. But what if the outage lasts for a few days, not just a few hours? And for a larger enterprise, the cost for a minute of downtime can be far, far greater.
The impact of a lengthy internet outage can reach well beyond direct costs. A business’s reputation is harmed if it cannot serve its customers, or if a deadline is missed because employees couldn’t access online tools. A lost customer is a cost that extends well beyond the time internet service is restored.
Internet backup alternatives
It is quite clear that internet downtime can be very costly. It’s prudent to have a backup in place to avoid the costs, disruptions, and customer ill will that accompany an internet outage.
The main alternatives for internet backup are a second wired connection, cellular, and satellite. We will discuss each in turn.
Multiple wired connections
Many people assume - incorrectly, it turns out - that if one wired internet provider goes down, a different wired internet provider can provide backup. Occasionally this is correct, but more often failures of wired connections occur in the “last mile,” or the connection to the customer, often because someone cut a cable with a backhoe. In such a situation, all wired internet connections are likely to be down because they are all channeled through the same junction. It is much safer to have a backup that goes to a completely different WAN technology and routing.
Cellular failover
As the name implies, cellular failover automatically reroutes internet traffic to a cellular connection if the primary wired internet connection fails. With high-speed 5G and LTE coverage now available to 98% of the population of America, fast and reliable cellular data is available to almost every business.
Satellite
A third alternative is to failover to a satellite internet connection. While satellite internet service has become more widely available in the last few years, for an equivalent amount of bandwidth, it is still more expensive, and maximum speeds will still be less than a cellular connection. Plus, technical performance parameters are not as good as cellular. However, if the cellular coverage in an area is limited, satellite can be an excellent option.
How to choose between WAN failover alternatives?
WAN (Wide Area Network) failover is the networking term used for “internet backup.”
In the vast majority of use cases, cellular failover is the technique of choice. Widely available, reliable, excellent bandwidth, attractive cost, all make cellular failover the best option for most companies.
Many apps used by businesses require a high-performance internet connection. They may be sensitive to jitter and latency. Average latency for a cellular connection is only about 100 milliseconds, versus 550 milliseconds for a satellite connection.
Another advantage of using cellular is that it can be rapidly deployed. There can be a delay of weeks or even months in getting wired connectivity to a new office. With 5G or LTE, a new office can be up and running in a day. Putting a dual-WAN router on day one makes it easy to make the wired connection primary when it is available.
In “digital deserts” - remote locations that have no wired internet available at all – Fixed Wireless Access (FWA) with cellular as the primary internet connection may use satellite for the backup. With 5G speeds able to rival wired connections, FWA is becoming increasingly common.
Some companies also use satellite as a tertiary backup, in the unlikely scenario where both wired and cellular connectivity go down at the same time.
SD-WAN and cellular failover
SD-WAN (Software-Defined Wide Area Network) provides an overlay to multiple network access connections whether fiber, cable, cellular, and satellite. SD-WAN automatically routes traffic to the optimal connection based on predetermined parameters such as bandwidth and link performance. With SD-WAN in place, traffic can be automatically routed to a cellular connection not only when the wired connection fails, but as a supplemental path either as an active link or on standby.
Failover hardware configurations
There are different ways that hardware can be configured for network failover, depending on the IT environment and needs of the business.
In an office that already has a router that can accommodate failover, the simplest thing is to add a 5G or LTE adapter that simply is a conduit for cellular access.
A dual WAN failover router is designed as a purpose-built router with ports, interfaces, and software that optimizes it to support both fiber/wired connections and 5G/LTE wireless connectivity. These can be connected to a service gateway or cloud to enable SD-WAN with advanced performance and cybersecurity features.
What to look for in WAN failover (internet backup) setups
There are many factors to consider in choosing your WAN failover setup:
- Adequate bandwidth
- Suitable technical performance
- Do you want simple failover, or do you prefer WAN load balancing to optimize performance?
- Does the hardware support easy troubleshooting - for example, with Out of Band Management (OOBM) - to allow analyzing the problem when the primary connection goes down?