Reliable and Low-Latency Fronthaul for Tactile Internet Applications

With the emergence of Cloud-RAN as one of the dominant architectural solutions for next-generation mobile networks, the reliability and latency on the fronthaul (FH) segment become critical performance metrics for applications such as the Tactile Internet. Ensuring FH performance is further complicated by the switch from point-to-point dedicated FH links to packet-based multi-hop FH networks. This change is largely justified by the fact that packet-based fronthauling allows the deployment of FH networks on the existing Ethernet infrastructure. This paper proposes to improve reliability and latency of packet-based fronthauling by means of multi-path diversity and erasure coding of the MAC frames transported by the FH network. Under a probabilistic model that assumes a single service, the average latency required to obtain reliable FH transport and the reliability-latency trade-off are first investigated. The analytical results are then validated and complemented by a numerical study that accounts for the coexistence of enhanced Mobile BroadBand (eMBB) and Ultra-Reliable Low-Latency (URLLC) services in 5G networks by comparing orthogonal and non-orthogonal sharing of FH resources.Comment: 11pages, 13 figures, 3 bio photo

Latency Bounds of Packet-Based Fronthaul for Cloud-RAN with Functionality Split

The emerging Cloud-RAN architecture within the fifth generation (5G) of wireless networks plays a vital role in enabling higher flexibility and granularity. On the other hand, Cloud-RAN architecture introduces an additional link between the central, cloudified unit and the distributed radio unit, namely fronthaul (FH). Therefore, the foreseen reliability and latency for 5G services should also be provisioned over the FH link. In this paper, focusing on Ethernet as FH, we present a reliable packet-based FH communication and demonstrate the upper and lower bounds of latency that can be offered. These bounds yield insights into the trade-off between reliability and latency, and enable the architecture design through choice of splitting point, focusing on high layer split between PDCP and RLC and low layer split between MAC and PHY, under different FH bandwidth and traffic properties. Presented model is then analyzed both numerically and through simulation, with two classes of 5G services that are ultra reliable low latency (URLL) and enhanced mobile broadband (eMBB).Comment: 6 pages, 7 figures, 3 tables, conference paper (ICC19

An SDR-Based Experimental Study of Reliable and Low-Latency Ethernet-Based Fronthaul with MAC-PHY Split

Cloud-Radio Access Network (RAN) is one of the architectural solutions for those mobile networks that aim to provide an infrastructure that satisfies the communication needs of a wide range of services and deployments. In Cloud-RAN, functions can be flexibly split between central and distributed units, which enables the use of different types of transport network. Ethernet-based fronthaul can be an attractive solution for Cloud-RAN. On the one hand, the deployment of Ethernet-based fronthaul enables Cloud-RAN to provide more diverse, flexible and cost-efficient solutions. On the other hand, Ethernet-based fronthaul requires packetized communication, which imposes challenges to delivering stringent latency requirements between RAN functionalities. In this paper, we set up a hardware experiment based on Cloud-RAN with a low layer split, particularly between medium access control and the physical layer. The aim is to demonstrate how multi-path and channel coding over the fronthaul can improve fronthaul reliability while ensuring that: (i) latency results meet the standard requirements; and (ii) the overall system operates properly. Our results show that the proposed solution can improve fronthaul reliability while latency remains below a strict latency bound required by the 3rd Generation Partnership Project for this functional split

An SDR-Based Experimental Study of Reliable and Low-Latency Ethernet-Based Fronthaul with MAC-PHY Split

Cloud-Radio Access Network (RAN) is one of the architectural solutions for those mobile networks that aim to provide an infrastructure that satisfies the communication needs of a wide range of services and deployments. In Cloud-RAN, functions can be flexibly split between central and distributed units, which enables the use of different types of transport network. Ethernet-based fronthaul can be an attractive solution for Cloud-RAN. On the one hand, the deployment of Ethernet-based fronthaul enables Cloud-RAN to provide more diverse, flexible and cost-efficient solutions. On the other hand, Ethernet-based fronthaul requires packetized communication, which imposes challenges to delivering stringent latency requirements between RAN functionalities. In this paper, we set up a hardware experiment based on Cloud-RAN with a low layer split, particularly between medium access control and the physical layer. The aim is to demonstrate how multi-path and channel coding over the fronthaul can improve fronthaul reliability while ensuring that: (i) latency results meet the standard requirements; and (ii) the overall system operates properly. Our results show that the proposed solution can improve fronthaul reliability while latency remains below a strict latency bound required by the 3rd Generation Partnership Project for this functional split