End-to-End QoS Improvement of HSDPA End-User Multi-flow Traffic Using RAN Buffer Management

TL;DR

This paper proposes an enhanced RAN buffer management scheme for HSDPA that improves end-to-end QoS for multi-flow sessions, especially benefiting non-real-time traffic without affecting real-time flow quality.

Contribution

It introduces a dynamic TSP-based buffer management enhancement for HSDPA that optimizes QoS for concurrent real-time and non-real-time flows in multi-flow sessions.

Findings

QoS for NRT flows is improved with the new scheme.

RT flow QoS remains unaffected by the enhancements.

End-to-end performance gains are demonstrated through system-level simulations.

Abstract

High Speed Downlink Packet Access (HSDPA) was introduced to UMTS radio access segment to provide higher capacity for new packet switched services. As a result, packet switched sessions with multiple diverse traffic flows such as concurrentvoice and data, or video and data being transmitted to the same user are a likely commonplace cellular packet data scenario. In HSDPA, Radio Access Network (RAN) buffer management schemes are essential to support the end-to-end QoS of such sessions. Hence in this paper we present the end-to-end performance study of a proposed RAN buffer management scheme for multi-flow sessions via dynamic system-level HSDPA simulations. The scheme is an enhancement of a Time-Space Priority (TSP)queuing strategy applied to the Node B MAC-hs buffer allocated to an end user with concurrent real-time (RT) and non-real-time (NRT) flows during a multi-flow session. The experimental multiflow scenario is a packet voice call with concurrent TCP-based file download to the same user. Results show that with the proposed enhancements to the TSP-based RAN buffer management, end-to-end QoS performance gains accrue to the NRT flow without compromising RT flow QoS of the same end user session.