The cellular network is quickly replacing traditional satellite links in suitable areas to carry live streaming traffic due to its simplicity, flexibility, and cost-effectiveness. In order to provide redundancy and increase the link capacity, bonded cellular technologies have been developed to provide fault-tolerance and high-speed links between site and studio.

I recently tested the Pepwave MAX Transit Duo LTE-A router recently and the results are very promising in both performance and resilience.

What it is?

Peplink’s SpeedFusion is a packet-level bonding technology, which breaks down network sessions and send packets through all available WAN connections. The end-user can configure the traffic distribution and protection level based on the needs and network environment. SpeedFusion Technology can provide hot fail-over between WAN connections, forward error connection of tunnel traffic, WAN smoothing and user-controlled traffic distribution and steering. These features make it a suitable protocol to carry video for streaming applications.

Standard SpeedFusion requires minimum two Peplink routers or one Peplink router and one FusionHub virtual instance to form an end-to-end SpeedFusion VPN tunnel. Peplink also provides SpeedFusion Cloud plans for users to connect to Peplink-hosted environments in different geographical regions. This provides flexibility for an end-user’s production requirements and is also suitable for start-up users who have only one Peplink router hardware device.

speedfusion cloud

What are the benefits of using SpeedFusion to deliver video streaming?

First of all, bonded bandwidth can eliminate the upload bottleneck with a single WAN or cellular connection. In an ideal environment, a single cellular connection can give you ~100Mbps usable upload bandwidth in Sydney’s populated areas and near to an ISP base station, but even that is not guaranteed performance. The performance you achieve is hugely dependent on the current traffic load on your attached base station. In other words, the people near you can affect your cellular service’s quality. On the other side, a cable service or FTTB service usually provides even less throughput performance.

In my opinion, at least in the foreseeable future, it is not practical or optimal to use a single WAN connection to carry real-time video streams over the public Internet for production purposes.

Redundancy in bonded cellular has three requirements:

  1. Link redundancy – the capability of handling uninterrupted streaming when one of the WAN connections is unstable or out-of-service
  2. Packet recovery – the capability of reassembling all network packets correctly when some traffic has been lost during transmission
  3. Seamless recovery – when an unstable link is recovered, it should be added to the service group without user interaction

SpeedFusion can certainly achieve these three requirements by adopting several very clever mechanisms including link health detection, service cut-off criteria, forward error correction, and more.

SpeedFusion allows end-users to customise the traffic distribution and fail-over criteria based on use cases. You can steer different types of traffic to different tunnels, sub-tunnels or simply send out from an individual WAN connection, based on each type of traffic’s SLA requirements.

For cellular usage, end-users can set roaming allowance and data allowance to avoid unattended roaming usage or expensive data rate when data usage goes over the current cellular plan’s fixed rate cap. When the device is used in a broadcast site with fixed line Internet or Wi-Fi available, users can also join these WANs and use a mixture of cellular WAN, Ethernet WAN and Wi-Fi to carry the data.

If you are an experienced user, you can also fine-tune the protocol parameters by manually select acceptable cellular signal level, WAN link cut-off latency threshold, traffic distribution ratio, and other parameters to best utilise the network resources.

Can 5G network replace cellular bonding technology?

My answer is no. Some people might disagree with me because 5G is being rolled out so quickly and it is designed to carry much larger throughput than LTE. This is true and not true – 5G is designed to have better power spectral density, but real-world performance is also limited by your end device’s RF capability and ISP’s allowance.

The screenshot below records the best 4G and 5G performance I manage to achieve beside a Telstra base station. You can see that the 5G download performance is tripled while upload performance is very similar to 4G.

5g vs lte

For remote production and real-time video streaming applications, we rely on the upload speed to deliver the work. Cellular bonding is still critical to guarantee adequate and stable upload speed from remote site to studio, plus its added value such as link redundancy and packet recovery cannot be provisioned by 5G itself.

Next Steps

Digistor is Australia's leading expert in utilising the latest technologies for live and remote production. If you have an application you'd like to discuss, contact us so that we can explore together the best solution for you. We have equipment and demonstration facilities at our offices in Sydney and would welcome the opportunity for a "hands on" discovery session.