Why the transport network is key to supporting new 5G capabilities

Why the transport network is key to supporting new 5G capabilities

By Dave Sinicrope, Director of the Access and Transport Architecture (ATA) Work Area, with Ericsson 

5G is growing exponentially and will unlock a host of use cases across an array of different industry verticals. However, 5G networks also bring increased complexities and operators must ensure their transport networks can meet these rigorous demands. Broadband Forum and its members continue to place emphasis on this area as it standardizes the architecture to allow carriers to manage their services easily and in a holistic manner.

For 5G, a highly scalable and future-proof network architecture – including intelligent, coordinated automation of: 1. the RAN, 2. the mobile core and 3. the transport networks – is required to enable deployment and operation of new revenue generating services. The transport architecture is key to this, providing the necessary standard interfaces, requirements, and modeling to realize this intelligent, coordinated automation.

The future of 5G transport

As the complexities of 5G networks emerge, it has never been more critical to have an intelligent, automated coordination between the RAN, the mobile core networks and the transport network. With 5G bringing a significant increase in capacity, along with more stringent requirements in regard to performance including lower predictable delay, loss, and jitter, it requires an estimated doubling of radio sites deployed and the need for architecture with new RAN and core interfaces. These requirements must not only be met by mobile equipment but also by the underlying transport network.

A new white paper from Broadband Forum, entitled “5G Network Architecture Overview”, outlines the motivation, architecture and requirements to achieve these new requirements. It highlights how operators need to upgrade existing transport systems to provide sufficient capacity and performance to the RAN and mobile core parts of the network. This will meet the suite of new demands and ensure superior RAN performance while maintaining low total cost of ownership. Increased capacity and greater interface density are among the requirements that need to be addressed – for example, 5G backhaul baseband interfaces will need 10 Gbps capacity and need to scale efficiently up to 100Gbps.

Realizing the vision

When it comes to upgrades, operators are often faced with the dilemma of balancing the need to incorporate the latest technology developments into their network while protecting their previous investments and maintaining service guarantees such as availability. Choosing to migrate their existing networks is often deemed the most cost-effective option. For this, standards that consider and prioritize backward compatibility and migration are immensely important as they ensure any upgrade will work with current networks, protecting operators’ existing investments.

This is why, Broadband Forum is developing its 5G Transport Architecture and Requirements specification (WT-521), a continuation of the architecture created for 2G through to LTE-Advanced described in TR-221, TR-224 and TR-350. The specification leverages IPv6, segment routing, MPLS, Ethernet VPN (EVPN) and other technologies to enable deterministic, effective and scalable transport networks to support operator 5G deployments; not only standalone, but in coexistence with LTE and 4G deployments.

Shaping the future of broadband

The 5G Transport project is among the initiatives Broadband Forum will continue to progress during its virtual Q3 meeting which will be held from Monday, August 31 to Thursday, September 3. It is just one aspect of Broadband Forum’s 5G work which also includes a Fixed Mobile Convergence project with 3GPP to produce a specification for a 5G Access Gateway Function (AGF) that adapts fixed access onto the 5G core. Additionally, in the Forum’s Access and Transport Architecture (ATA) Work Area, specifications for measuring, analyzing and scaling the Internet Protocol (IP) capacity and Quality of Service of the transport networks noted above are also underway. These new measurement methods overcome the shortcomings of today’s Transmission Control Protocol (TCP) based, capacity-centric network equipment and analysis to accurately measure connectivity at 1Gbps and above.

To join the virtual Q3 meeting and get involved in developing the specifications that will drive the future of 5G, stay tuned for the registration information here. If you are considering membership in Broadband Forum to actively participate or would simply like to observe the meeting,  please contact Rhonda Heier at rheier@broadband-forum.org.