Broadband Forum: 5G Transport Network Architecture and Requirements

The Broadband Forum published a new white paper that outlines the transport architecture it is developing and sets out the motivation and benefits for operators to upgrade their transport networks and ensure their legacy backhaul infrastructure meets a new suite of demands to ensure superior RAN performance and maintain low total cost of ownership for 5G.

“5G is driving mobile operators to take a holistic approach to transport network planning,” said Robin Mersh, CEO of Broadband Forum. “The technology also brings a significant increase in capacity, requires an estimated doubling of radio sites deployed, and the need for a new architecture with new RAN and Core interfaces. These new architectures and new interfaces each have specific requirements that must be met not only by the mobile equipment, but by the underlying transport network.”

The white paper – titled “5G Network Architecture Overview” – explains that the new complexities of 5G networks require intelligent, automated coordination between RAN, mobile core networks and the underlying transport network to meet the demands of 5G. Legacy transport systems need to be upgraded and backhaul systems must meet a suite of new demands to ensure superior RAN performance and maintain low total cost of ownership. 5G backhaul systems need to address increased capacity and greater interface density requirements. For example, 5G backhaul baseband interfaces will need 10 Gbps capacity and need to scale efficiently up to 100Gbps.

The white paper has been released in advance of Broadband Forum’s new 5G Transport Architecture and Requirements specification which introduces the use of new transport and routing technologies and applies these to the 5G split RAN architecture. The standard will leverage IPv6, segment routing, MPLS, Ethernet VPN (EVPN) and other technologies to enable effective and scalable transport networks to support operator 5G deployments, in conjunction with LTE and 4G operations.

“While the initial focus in 5G is on potential use cases and the radio technology itself, 5G cannot exist without a transport network to support it,” said Joel Halpern, Editor of the 5G Network Architecture white paper, of Ericsson. “Technology and application performance requirements will lead to a future transport network that looks very different. The use of 5G network architecture requirements, such as those being created within Broadband Forum, will ensure operators can enhance and migrate their existing networks to support the new capabilities 5G needs in order to deliver on the promise it has while protecting their existing investment.”

Broadband Forum’s other 5G initiatives are also continuing. These include a joint Fixed Mobile Convergence project with 3GPP and a specification for a 5G Access Gateway Function (AGF) that adapts fixed access onto the 5G core. Specifications for measuring, analyzing and scaling the capacity and Quality of Service of the transport networks noted above are also underway in the Forum’s Access and Transport Architecture (ATA) Work Area. These overcome some of the shortcomings of today’s capacity-centric and node-centric network equipment and analysis.

https://www.broadband-forum.org/projects/5g