WAN link bonding is not a silver bullet: ensuring stable connectivity for emergency services in the field

Demand for Low Earth Orbit (LEO) satellite connectivity solutions, such as Starlink, is expected to grow, given that it is now available for customers in rural and remote parts of Australia in partnership with some of Australia’s leading telecommunications service providers. While Starlink provides high levels of coverage, there are disadvantages of using satellite for primary WAN communications, especially in emergency services. Limitations of satellite technologies compared with 4G/5G, especially in a moving vehicle, include penetration through objects, performance speed, performance latency, capacity, and cost.

Best of Breed Connectivity

Organisations looking to implement best practice when it comes to uptime, latency, and speed should consider cellular and LEO satellite technologies as complementary solutions. Cradlepoint enables enterprise organisations to seamlessly combine LEO satellite with 5G and other WAN sources such as 4G and Wi-Fi as WAN. Why is this important? Because in most scenarios, remote businesses need a combination of cellular and satellite solutions to ensure they have uninterrupted connectivity.

What is network bonding?

You may have heard about WAN bonding. WAN link bonding combines two types of WAN connections into one virtual connection, with the intent of providing more bandwidth and seamless failover if one of the physical WAN connections fails. WAN bonding generally consists of different features based on whether the organisation is looking to increase WAN resiliency for mission-critical traffic or increase the aggregate bandwidth available for bandwidth-intensive applications. These features include:

• Aggregated bandwidth — where the bonded link will offer aggregated bandwidth of all member links for higher throughput.
• Weighted flow distribution — traffic flows will be distributed based on % weights configured on each member link.
• Flow duplication — traffic flows will be duplicated across the member links to ensure no traffic loss for mission critical traffic.
   

SD-WAN providers are touting the benefits of WAN bonding with satellite technologies; however, organisations need to know the facts when considering satellite with WAN bonding as their connectivity solution. WAN bonding is not a silver bullet when it comes to stability and bandwidth of connectivity. Here is why:

1. Cost — Satellite service providers like Starlink offer customers a data cap. So, when a customer bonds two connections together (cellular and satellite), that means that all data is running over both networks all the time. Data costs can max out very quickly and customers are faced with very high data costs.
2. Loss of useable bandwidth — With WAN bonding, data packets are sent via the different available networks, but the process isn’t complete until the last packet arrives at the final destination, to allow for the data packets to be reassembled into useable data. Because of this, WAN bonding uses the slowest speed available (often the satellite speed) to deliver data.

Using Cradlepoint 5G with satellite for failover doesn’t pose the same challenges as WAN link bonding. A couple of reasons for this:

1. Customers won’t need to pay for unnecessary data usage. By using Cradlepoint 5G connectivity in use cases like emergency services vehicles, organisations will benefit from the high speed and low latency of 5G and only use satellite connectivity as failover, when and where 5G connectivity isn’t available. This keeps data costs down and connectivity speed and availability up.
2. Cradlepoint’s 5G-optimised SD-WAN solution, as part of Cradlepoint’s NetCloud Exchange (NCX), enables organisations to set and have complete control over failover commands. IT teams can instruct the network to failover from 5G to satellite when 5G signal strength gets below a certain level. By moving the cellular WAN connection to satellite before it actually fails, Cradlepoint prevents data transfer sessions from breaking, resulting in smooth, uninterrupted connectivity.

Is there a use case where WAN link bonding is a good solution?

Yes. WAN bonding is useful where there’s an emergency services vehicle for example, which is deployed in a metropolitan area where 5G signal drops in and out constantly over a specific area that is travelled, thus causing the network to switch from cellular to satellite and back ongoing over a journey. In this case, WAN bonding would be a good solution to ensure the best connectivity possible.

Primary vs Failover

Deciding whether cellular or satellite should be the primary connectivity solution for emergency services organisations depends on a number of things, such as locations they service and the environment of those locations (are there tall buildings that might block satellite view or are there few 5G towers operating in the area).

Cradlepoint can be used for primary connectivity by combining 5G, 4G, Wi-Fi as WAN and Starlink simultaneously. Cradlepoint’s SD-WAN solution can be deployed to dynamically select the best performing WAN source based on user defined criteria to ensure real-time applications have the best user experience.

Cradlepoint supports load balancing options and application aware traffic steering to allow the simultaneous use of all available WAN sources. Critical application can be prioritised to use the best available WAN source and switch dynamically as conditions change. For example, emergency services in-vehicle telemetry traffic would always be prioritised to use the best available WAN source and noncritical traffic would be limited to the lower-performing links.

Cradlepoint’s central network management platform, NetCloud Manager, features true Cellular Intelligence. It provides a single pane of glass to manage sites, vehicles, and IoT by orchestrating policies to ensure applications use the best available WAN source and have the appropriate security protection applied.

If using Starlink for primary connectivity, during a Starlink outage, using Cradlepoint for redundancy can seamlessly switch the connection to 5G, 4G or Wi-Fi as WAN.

So even as a failover option, Cradlepoint enhances the Starlink experience as an additional option when reliable connectivity is required for real-time applications (for example Telemetry, VoIP, and connected tools like fire protection masks or police armour holsters). Cradlepoint also enables critical applications to move seamlessly between Starlink and 5G and/or 4G when the Starlink service is degraded or unavailable due to challenges with getting a clear line of sight to the sky or if there are adverse weather conditions.

Image credit: iStock.com/Kinwun