How to manage mobile video with Open RAN

Ever since the launch of 4G, video has been a thorny issue to manage for network operators. Most of them had rolled out unlimited or generous data plans, without understanding how video would affect their networks and economics. Most videos streamed to your phones use a technology called Adaptive Bit Rate (ABR), which is supposed to adapt the video’s definition (think SD, HD, 4K…) to the network conditions and your phone’s capabilities. While this implementation was supposed to provide more control in the way videos were streamed on the networks, in many cases it had a reverse effect.

 

The multiplication of streaming video services has led to ferocious competition on the commercial and technological front. While streaming services visibly compete on their pricing and content attractiveness, a more insidious technological battle has also taken place. The best way to describe it is to compare video to a gas. Video will take up as much capacity in the network as is available.

When you start a streaming app on your phone, it will assess the available bandwidth and try to deliver the highest definition video available. Smartphone vendors and streaming providers try to provide the best experience to their users, which in most cases means getting the highest bitrate available. When several users in the same cell try to stream video, they are all competing for the available bandwidth, which leads in many cases to a suboptimal experience, as some users monopolize most of the capacity while others are left with crumbs.

 

In recent years, technologies have emerged to mitigate this issue. Network slicing, for instance, when fully implemented could see dedicated slices for video streaming, which would theoretically guarantee that video streaming does not adversely impact other traffic (video conferencing, web browsing, etc…). However, it will not resolve the competition between streaming services in the same cell.

 

Open RAN offers another tool for efficiently resolving these issues. The RIC (RAN Intelligent Controller) provides for the first time the capability to visualize in near real time a cell’s congestion and to apply optimization techniques with a great level of granularity. Until Open RAN, the means of visualizing network congestion were limited in a multi-vendor environment and the means to alleviate them were broad and coarse. The RIC allows to create policies at the cell level, on a per connection basis. Algorithms allow traffic type inference and policies can be enacted to adapt the allocated bandwidth based on a variety of parameters such as signal strength, traffic type, congestion level, power consumption targets…

 

For instance, an operator or a private network for stadiums or entertainment venues could easily program their network to not allow upstream videos during a show, to protect broadcasting or intellectual property rights. This can be easily achieved by limiting the video uplink traffic while preserving voice, security and emergency traffic.

 

Another example would see a network actively dedicating deterministic capacity per connection during rush hour or based on threshold in a downtown core to guarantee that all users have access to video services with equally shared bandwidth and quality.

 

A last example could see first responder and emergency services get guaranteed high-quality access to video calls and broadcasts.

 

When properly integrated into a policy and service management framework for traffic slicing, Open RAN can be an efficient tool for adding fine grained traffic optimization rules, allowing a fairer apportioning of resource for all users, while preserving overall quality of experience.