On Maximizing VoIP Capacity and Energy Conservation in Multi-Rate WLANs

Abstract

This letter highlights a key problem that arises when frame aggregation, a popular method for boosting VoIP capacity, is used in Wireless Local Area Networks (WLANs) that employ asynchronous power save mode (PSM). Specifically, it shows how the PSM proposed by the Wi-Fi Alliance renders frame aggregation ineffective. It then proposes a novel opportunistic scheduler that restores the benefits of frame aggregation whilst ensuring stations have minimal energy expenditure. Keywords era2015 Disciplines Physical Sciences and MathematicsPublication Details K. Chin, "On maximizing VoIP capacity and energy conservation in multi-rate WLANs," IEEE Communications Letters, vol. 14, (7)

Energy efficient VoIP communication using WSN clustering approach

“…Higher data rate needs more power [3], [4] which makes energy consumption as a major issue both in wireless sensor network as well as in mobile networks. VoIP service consumes the considerable amount of battery as compared to other services.…”

“…Various schemes were developed and implemented successfully such as Opportunistic scheduler [4] and Greencall algorithm [2] based on the Power Saving Mode (PSM). Though the quality of the performance is maintained, it does not satisfy the requirement of saving sufficient battery power [3].…”

“…Nowadays mobile phones with evolutionary technologies (such as 3G, 4G LTE) are dominating the market of cellular communication systems [1], [3], [4]. 978-1-4673-4463-0/13/$31.00 ©2013 IEEE These phones have been provided with better hardware and are becoming more powerful day by day.…”

Improving the energy efficiency of VoIP applications in IEEE 802.11 networks through control of the packetization rate

“…Preserving VoWiFi quality of service (QoS), along with saving battery in the portable device are two research fields with abundant literature predominantly focused on the link layer [1], [2], [3].…”

“…Research efforts to support quality in VoWiFi have been focused on two main approaches: (a) dimensioning works aimed at finding the maximum number of simultaneous VoIP flows that IEEE 802.11 networks can accommodate while satisfying QoS constraints (e.g. network delay, packet loss ratio) [5], [6], [7], [8], [1], [2]; and (b) link-layer proposals aimed at meeting QoS constraints in the IEEE 802.11 network by finding optimum values for MAC-layer variables such as contention window size, maximum retry limits, etc. [9], [10], [11], [12].…”