Nokia Bell Labs Demonstrates Ultralow Latency for 5G Mobile Transport

Low latency is one of the specifications of 5G networks. The challenges operators face in implementing this feature is getting more difficult as mobile traffic continues to grow at an incredible pace. The Internet of Things (IoT), 4K and 8K video, streaming service and video communications are but a few of the applications waiting for 5G. Nokia (News - Alert) Bell Labs just announced it has developed a solution that will allow operators to re-use existing fiber-to-the-home (FTTH) massive-scale deployments to address the issues of latency and capacity for mobile transport, not only for 5G in the future, but also existing 4G networks.

The emphasis on latency is being pushed to the forefront because many of the services over 5G networks will have to be delivered in real-time or very near real-time. Nokia is using commercial next generation PON (NG-PON) to transport ultra-low latency CPRI streams via a standard single fiber running between the Baseband Unit (BBU) and the Remote Radio Head (RRH).

The company showed existing fiber networks can be used to cost-efficiently transport mobile traffic and help accelerate 5G in a proof-of-concept demonstration according to the latency budget requirements for the fronthaul of commercial radio equipment.

Nokia Bell Labs (News - Alert) explained fronthaul is key to the C-RAN (Centralized Radio Access Network) architecture in mobile networks, because this is where the processing power is centralized and moved away from the cell sites.  The interfaces for next generation fronthaul need ultra-low latency transport, which, according to Nokia, are in the sub-millisecond range as 4G and 5G technologies require strict timing and synchronization.

Peter Vetter, head of Access Research at Nokia Bell Labs, said, “This is an important milestone in the industry and in the advancement of 5G, showing for the first time how a PON network can effectively be used to support very high capacity, low latency applications. It demonstrates the flexibility of PON to support traditional CPRI and evolving mobile specifications, such as fronthaul over simpler native Ethernets, and validates the readiness of PON for the 5G era.”

The use of next generation PON technology was validated by Nokia Bell Labs, with the company saying XGS-PON technology can accomplish the timing constraints, while delivering the necessary capacity in a manner that is cost effective for mobile cell site transport. By running on fiber access networks, XGS-PON makes it possible for operators to use GPON technologies and platforms to provide high-capacity services.

Operators can now use existing passive optical networks in Fiber-to-the-home or Building (FTTH/FTTB) deployments to handle mobile transport traffic as more cell sites are installed. 

Nokia Bell Labs is using existing fixed fiber networks because the infrastructures that are in place are massive in scale, making them ideal to support 5G.