How Ericsson and Telefónica built a cutting edge 5G-ready transport solution
Ericsson and Telefónica have together successfully showcased a traffic-agnostic 5G-ready transport solution for both Radio and Fixed Enterprise Access. It is based on Ericsson’s groundbreaking and future-proof eXhaul concept, which allows a wide range of transport technologies, including CPRI, eCPRI and Ethernet, to efficiently and securely share the same physical infrastructure.
Researchers in the eXhaul project are working to create a transport system able to concurrently support any type of fronthaul and backhaul services within the full range of different operator network scenarios. In order to validate and test this new network concept in real use cases, we carried out a joint trial with Telefónica. To support legacy, current and future mobile systems, such as 3G, 4G, 5G and enterprise connectivity, a convergent infrastructure solution was viewed as a fundamental prerequisite.
eXhaul is a convergent and traffic-agnostic transport concept for supporting current and future fronthaul interfaces, for example, CPRI and eCPRI, Elastic RAN, and Ethernet. It meets the tight requirements for latency, jitter, synchronization, and high capacity required by 5G, and allows for a smooth network evolution towards 5G according to specific operator needs.
The joint activity on the eXhaul concept stems from the participation of both Ericsson and Telefónica in the EU H2020 5G-Crosshaul project, in which different options for converged fronthaul and backhaul networks were investigated. The eXhaul activity concluded this year with the development of a proof-of-concept, which was integrated into 5TONIC, Telefónica’s open 5G technologies innovation research lab in Madrid and showcased on November 16.
The demo highlighted the automatic configuration of enterprise services on the convergent transport for different radio splits, in order to simplify operational activities. During the showcase, an overview of the solution was presented, including research findings such as photonic technologies, networking aspects, control and the migration path from legacy to 5G.
eXhaul is a modular solution that combines the advantages of an agnostic transport system able to support any type of service with the benefits of wavelength-division multiplexing (WDM) networking. This allows transport at a low cost using heterogeneous wavelength channels at any bit rate (10, 25, 50, 100G), thus optimizing the use of installed optical fiber. To achieve this, the following building blocks were addressed to reach the right cost, power consumption, and size targets:
- An agnostic (electric) switch, integrated with an optical switch (a mini-ROADM designed for this purpose)
- A high-capacity WDM transmission suitable for radio access (that is, with a suitable cost figure and the required performance)
- A smart controller able to mix the different types of fronthaul and backhaul traffic to fulfill radio needs and optimize transport resources.
Moreover, the solution provides efficient slicing to simplify operations. All of the above can be accomplished with any physical topology (for example, a ring to assure the best resilience, a tree re-using Gigabit Passive Optical Network (GPON) infrastructure, or a bus-like G.metro, among others).
The joint research on the eXhaul concept will continue in the coming months, focusing on topics such as the simplification of the configuration of the nodes in the last network segment to reduce operational costs and facilitate interworking with the aggregation network. We will also explore how eXhaul can serve as convergent transport for relevant IoT use cases.