Abstract
With the advancement of the Long-Term Evolution (LTE) network and smart-phones, most of today’s internet content is delivered via cellular links. Due to the nature of wireless signal propagation, the capacity of the last hop link can vary within a short period of time. Unfortunately, Transmission Control Protocol (TCP) does not perform well in such scenarios, potentially leading to poor Quality of Service (QoS) (e.g., end-to-end throughput and delay) for the end user. In this work, we have studied the effect of Active Queue Management (AQM) based congestion control and intra LTE handover on the performance of different Medium Access Control (MAC) schedulers with TCP traffic by ns3 simulation. A proper AQM design in the Radio Link Control (RLC) buffer of eNB in the LTE network leads to the avoidance of forced drops and link under-utilization along with robustness to a variety of network traffic-loads. We first demonstrate that the original Random Early Detection (RED) linear dropping function cannot cope well with different traffic-load scenarios. Then, we establish a heuristic approach in which different non-linear functions are proposed with one parameter free to define. In our simulations, we demonstrate that the performance of different schedulers can be enhanced via proper dropping function.
Highlights
To meet the key requirements for the generation wireless network, cellular operators around the world provide seamless Quality of Service (QoS) for converged mobile and multimedia services.This is possible due to the deployment of 4G networks based on the Long-Term Evolution (LTE)standard
We have extended our idea Smart Random Early Detection (RED) (SmRED) [7] to SmRED-i, where packet dropping probability function is different in accordance with the value of i = 2, 3, 4 . . . Increasing the value of i will lead to lower dropping probability during low traffic-load condition and high dropping probability during high traffic-load condition
Both downlink and uplink packet schedulers are deployed at the eNB, and, since there is no inter-channel interference provided by Orthogonal Frequency Division Multiple Access (OFDMA), they work with a granularity of one Transmission Time Interval (TTI) and one Resource Block (RB) in the time and frequency domain, respectively
Summary
To meet the key requirements for the generation wireless network, cellular operators around the world provide seamless Quality of Service (QoS) for converged mobile and multimedia services. LTE introduces a new air interface and radio access network, which provides much higher throughput and low latency, greatly improved system capacity and coverage compared to those of the Wideband Code Division Multiple Access (WCDMA) systems. These improvements lead to increased expectations on the end-user Quality of Experience (QoE) over LTE as compared to existing 2G/3G systems [2]. To guarantee high throughput and low delay when congestion occurs, numerous studies on Active Queue Management (AQM) based congestion control schemes in the network have been proposed in the past, especially for transport-layer protocols.
Published Version (Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have