Transport networks have been the cornerstone on which new technologies were rolled out. 3G would not have been as ‘data-centric' if carrier ethernet was not simultaneously invented. 4G would not have been as ‘fast' if optical fiber had not been introduced. Finally, the always-available 5G will not be possible if fronthaul protocols such as CPRI (Common Public Radio Interface), eCPRI (enhanced CPRI) and OBSAI (Open Base Station Architecture Initiative) are not implemented.
While CPRI is the interface of choice for carrying fronthaul traffic on fiber, eCPRI is being designed to support stringent 5G performance requirements (especially latency and jitter), and to offer ethernet as a transport channel with the promise of a significant reduction in the required bandwidth. Here is the promise of CPRI and eCPRI: Ultra-low Bit Error Rates (10-12), low latency (RTT of 5 microsecs), low jitter and wander, and high data rates (up to 20 Gbps). But the promise is not enough; close monitoring is required to ensure that these new technologies/protocols are delivering.
In the virtualised world, the IP transport management is clearly a different ballgame than traditional transport management. It cannot be relegated to the background any more. Only a robust transport network will ensure that the new telco cloud, and its web-scale traffic is efficiently handled, and that ultra-high quality is continuously guaranteed.
However, we know from experience that no transport system is immune to failures, degradations, faults and poor performance. Despite real-time orchestration introduced into fronthaul, IP/MPLS, NFV and SDN to counter this, prevention of such undesirable network situations is highly recommended. For this, an emphasis on the service assurance of transport network is as critical as service assurance for the RAN and Core networks.
As fronthaul traffic throughput grows from current levels of 1 Gbps to more than 20 Gbps, rigorous monitoring will be required. Management of backhaul and fronthaul (Xhaul) in an integrated end-to-end view is critical to maintaining high quality of data as it passes through the entire hybrid network.
Mobile operators should look for performance assurance solutions that offer the following capabilities:
- Real-time, multi-domain, automated close-loop based troubleshooting to respond quickly to developing transport network problems.
- Adaptive threshold capabilities to identify abnormal performance.
- Offers usage forecasts to help network planning teams as well as orchestration systems to scale-up or scale-down capacity in real-time.
- Supports SLAs that have dependencies on the transport network
Thus, the integrated Xhaul transport assurance, will not just enable but accelerate the success of the virtualised C-RAN and core networks in 4G and 5G, in addition to optimising spend.
Check out our latest on-demand webcast: Pave the Way for 5G: C-RAN and Service Assurance and learn how to address RAN transformation challenges with Service Assurance solutions.