Bonded cellular and beyond

What is it, what is it used for, is it still relevant in a 5G world and, is it enough?

Cellular bonding refers to combining two or more cellular connections. The combination provides more bandwidth for uploads and downloads. It also provides connection resiliency in situations where cellular networks become congested due to high traffic, or in remote areas where cellular signal strength may be diminished.

There are many other factors that may impact cellular reception and the available bandwidth, which bonded cellular technology can address.

Key advantages of cellular bonding:

• Connection resiliency when networks are congested.
• Connection resiliency in fringe coverage areas.
• Greater upload and download bandwidth.
• Expanded coverage with carrier diversity.
   

Factors impacting cellular reception and available bandwidth
1. Obstructions (hilly terrain, dense foliage, large buildings).
2. Weather conditions (humidity, heavy cloud cover, fog, precipitation, electromagnetic interference, temp inversions).
3. Number of users.
4. Location (city, urban, rural).
5. Building materials (metal, concrete, tinted and low-e glass).
6. Data-intensive applications.
7. Spectrum bands.
8. Stationary versus in motion.
9. Proximity to tower.

Carrier diversity delivers greater resiliency

Carrier diversity: ie, using connections from different mobile network providers, delivers even greater resiliency. Should a connection drop, packet loss occur, available bandwidth diminish or the latency not meet the needs of the application, packets are re-routed across the other connections in the bonded link.

Upload and download speeds on mobile networks vary. While the global average download speed is 48 Mbps and upload speed is 12 Mbps, actual speeds vary greatly by country, carrier, specific location and the degree of congestion on the network. See diagram.

It is not unusual for users to only have 1 Mbps upload speed from a single connection, especially where crowds gather and cause network congestion, or in fringe coverage areas. But many applications require more than that. Take video as an example, approximately 5 Mbps upload bandwidth is required to send high-definition, low-latency live video. For 4K UHD streams, approximately 25 Mbps upload bandwidth is needed.

Applications relying on wireless internet connectivity, particularly those needing higher upload speeds to transmit uninterrupted high-quality live video or real-time data, can use multi-modem cellular bonding devices to aggregate multiple cellular connections to achieve the required bandwidth and connection resilience. These connections may be with the same or different carriers.

These devices use 3G/4G (including LTE)/5G modems to connect to the carrier networks.

Isn’t one connection enough?

While the upload and download bandwidth provided from a single carrier may be sufficient in a specific location, relying on a single connection leaves organisations vulnerable, especially if they need resilient connectivity while in motion: such as in a vehicle, or in nomadic situations where someone is moving from one location to another, but typically stationary. Mobile journalists and first responders are good examples of personnel that are frequently moving locations while they operate remotely.

No single carrier provides 100% coverage in every location. Carrier network coverage becomes an additional risk on top of the network congestion risk and the risk of degraded service in fringe coverage areas. For critical communications, carrier diversity is essential.

What about failover or load balancing solutions?

Failover solutions do not aggregate bandwidth, but instead use one connection at a time and switch to the next connection if the first connection fails. However, the performance of the first connection may degrade significantly before the failover occurs, providing a poor experience.

Meanwhile, load balancing solutions use a number of connections, but if a connection fails, the session is terminated and a new session must be initiated on another connection. This interruption is not acceptable for critical communications that depend on persistent connectivity.

What about 5G?

The arrival of 5G holds tremendous promise to transform telecommunications with faster speeds and less latency when connecting to the network, as well as enabling many more devices to connect to the internet. Yet despite this, connectivity challenges will remain. While the bandwidth from a single 5G connection may be sufficient for data-intensive applications, such as real-time, high-definition video, reliance on a single connection leaves organisations vulnerable and the coverage challenge remains.

Much like with 4G networks, carriers will have coverage gaps and ‘dead zones’ in cities and urban areas plus it will take time for 5G networks to roll out, especially networks using high-band millimetre wave (mmWave) spectrum that promises blistering speeds and low latency. Since 5G mmWave networks face greater challenges penetrating building materials than 4G LTE frequency bands, there are also implications for 5G coverage in buildings.

The higher power consumption required by 5G is another consideration. This is an important implication for portable, battery-powered devices used by personnel that operate remotely.

Since 4G LTE and 5G will co-exist for quite some time, choosing bonded cellular technology capable of aggregating the various generations of network technologies from multiple carriers remains key.

Resilient internet connectivity for critical communications

While bonding cellular connections may provide enough bandwidth for high-quality live video and real-time data exchange in mobile and nomadic scenarios, there are scenarios where aggregating other connections makes sense for greater connection diversity, resiliency and continuity.

From broadcasters and production companies, to public safety and government agencies, to enterprises spanning a wide variety of industries, organisations depend on internet connectivity for critical communications. In many situations, an unstable connection or a network outage is not simply an annoyance, it can have catastrophic implications.

Top image credit: ©stock.adobe.com/au/SasinParaksa