Mobile SD-WAN vs dual modems in vehicles

In emergency response, every second counts and reliable communication is critical. What happens when an in-vehicle network connection drops? No access to real-time dispatch updates, no critical data transfers, and potentially hampered communication with fellow responders. This scenario underscores the vital role of dependable connectivity in vehicles, especially when public safety is at stake.

By establishing network redundancy using a dual-modem router in vehicles, situations like this can be easily prevented. These routers provide automatic failover between two carriers, ensuring a seamless connection on the go. Think of it like a busy highway with two lanes — if one gets blocked, you can easily switch to the other. It’s an excellent option for staying connected even in spotty coverage areas. Mobile SD-WAN acts like a smart traffic director to increase reliability and optimise the network by utilising multiple connections simultaneously. This translates to more than just a backup — it means smoother operations and a truly resilient connection for an emergency services fleet.

How do dual-modem routers work?

A dual-modem router has two active radio connections, allowing SIM cards from different carriers to be active simultaneously. If one signal is degraded, the dual-modem router automatically switches from one carrier to another without downtime.

But what happens when there is no cellular coverage due to a natural disaster like a bushfire or severe flood taking out all local telecommunications towers? Dual-modem routers can accommodate multiple connectivity options, including cellular and satellite. This is of particular benefit to emergency services in Australia, in which there has been significant growth in the use of satellite technology over the last few years, due to limited available cellular coverage in regional parts of the country. Since 2020, hundreds of Disaster Satellite Service communications dishes have been installed around Australia on buildings such as Rural Fire Service depots as part of government programs. Also, various police and ambulance services have started rolling out satellite technology in their regional field vehicles.

How does SD-WAN work?

Imagine SD-WAN as a smart navigation system for your vehicles. It manages and directs traffic across a wide area network (WAN) using features such as intelligent traffic handling and link bonding. SD-WAN improves network performance and reliability by automatically selecting the best path for data and making it easier to manage and optimise your network.

Using SD-WAN on top of a dual-modem router guarantees the most reliable connection needed for mission-critical applications in vehicles, whether that be data from body-worn cameras or applications that allow police officers to search licence plates, for example.

In what situations do you need mobile SD-WAN?

Mobile SD-WAN is useful in practically any vehicle situation to help optimise connectivity and network performance.

Mission-critical communications

For different forms of mission-critical communication, SD-WAN enables features such as flow duplication for better reliability. Flow duplication effectively bonds two WAN connections to create an unbreakable WAN connection by duplicating and sending application data across both links.

Primarily used in vehicles, roaming between different cellular providers or between cellular and satellite networks, it automatically selects the two strongest links if more than two are available through a dual WAN router. This way, if one network is disrupted, there is congestion, or even a failure, applications will continue to function. This method uses double the data, so it should be reserved for the most essential traffic to save costs.

High-bandwidth applications

Often, a single connection isn’t sufficient for high-bandwidth applications like high-quality CCTV video streaming. SD-WAN can address this by aggregating bandwidth from both modem connections to create a fatter pipe, also known as link aggregation or link bonding. This technology merges multiple WAN interfaces into a single virtual connection, enhancing bandwidth, efficiency, and application resilience.

The benefits of using mobile SD-WAN in vehicles

While dual modems alone provide reliable cellular failover capabilities, mobile SD-WAN takes it a step further, giving organisations much more granularity, flexibility and control over network traffic.

With SD-WAN, organisations can monitor all applications on their network and establish policies for prioritising them. It also allows enterprises to implement more features, such as forward error correction (FEC), to improve resiliency, performance, and application quality of experience (QoE) across the WAN.

Forward error correction

When an application encounters weak signal quality, it tends to resend requests multiple times to maintain connectivity, consuming significant bandwidth. Using FEC can enhance application performance by reducing these repetitive retries, leading to a better QoE over unreliable connections and optimising bandwidth usage.

SD-WAN gives network administrators the ability to manage multiple WAN connection types with ease, using diverse connections to maximise application reliability and performance. Mobile SD-WAN takes that same capability on the road or in the field, giving emergency services organisations more efficient and stable connectivity options than ever before.

Top image credit: iStock.com/CatEyePerspective