This paper investigates the effects of different queuing regimes on the mean and standard deviation of the frame inter-arrival delay of a LTE traffic stream under the presence of background Ethernet traffic. The background traffic is used to represent traffic that would be generated by different functional subdivisions in the physical layer of traditional LTE base station. In this work, a Switched Ethernet architecture is used as the fronthaul section of a Cloud Radio Access Network (C-RAN). Contention in this fronthaul becomes an important issue since different traffic streams originating from different functional subdivisions with different quality of service specifications will be transmitted over the same physical links. Trunk ports then, will have to handle the queuing management and prioritization. Handling the traffic with different queuing regimes will reflect on the latency and latency variations of the LTE traffic. Keywords: Fronthaul, C-RAN, LTE, Ethernet, Background traffic. The fronthaul of the centralised access network proposed for the next mobile generation must comprise a transport infrastructure for different types of traffic between base station baseband units (BBU) and remote radio heads (RRH) [1] . As a means of reducing the data rate requirements of the future fronthaul, the implementation of different physical layer functional subdivisions (or "splits") has been proposed [1, 2] Furthermore, a combination of functional splitting with the use of Ethernet technology in the fronthaul can lead to cost reductions (by leveraging the ubiquity of Ethernet equipment) and performance enhancements (mainly from the ability to obtain statistical multiplexing gains [3]), in addition to the reduction in data rate requirements. At Ethernet switch ports, queuing and scheduling algorithms, such as weighted round robin (WRR) and strict priority (SP) can be employed to prioritize and manage the traffic and different transported services [4] . It is, then, important to investigate the efficiency of different queuing regimes and measure the effect of each on the radio traffic, when this co-exists with other streams in the fronthaul. In this work, Long-Term Evolution (LTE) sampled radio waveform traffic is generated and transported over a switched Ethernet fronthaul together with background traffic, which emulates traffic that would be generated by different functional splits in the access network. Specifically we focus on the effect of using the WRR with different weights and SP queuing regimes on the frame inter-arrival delay of the LTE traffic, when it contends with background traffic.
The effects of various queuing regimes such as strict priority and weighted roundrobin (WRR) on inter-arrival delays of CoE traffic streams are investigated in REF .
The effect of different queuing regimes on a Switched Ethernet fronthaul
2016 18th International Conference on Transparent Optical Networks (ICTON)
2016 18th International Conference on Transparent Optical Networks (ICTON)
Physics