Research Article

Delay, Reliability, and Throughput Based QoS Profile: A MAC Layer Performance Optimization Mechanism for Biomedical Applications in Wireless Body Area Sensor Networks

Table 3

Existing optimization mechanisms of the MAC layer CSMA/CA WBASN.

PaperConsidered MAC parametersContribution

Adaptive and real time protocols [20] Backoff exponent (BE)Analysis of macMinBE and macMaxBE values: by increasing these values the delay increases and the throughput decreases; however collision probability decreases and vice versa

Analysis of CAP [36]BEFor large networks, the throughput is independent of the BE initial value; however, for small networks it generates high impact

A comprehensive analysis of the MAC unreliability problem [37]Contention windows (CW)Propose CW values for time critical applications; higher values of CW reduce collision chances; however, for time critical applications where ACK is disabled the CW is set to lower values for fast communications

MAC unreliability problem in IEEE 802.15.4 WSN [38]Retransmissions In ideal channel conditions, when the number of retransmissions is increased from 1 to 2, a significant improvement is observed in packet delivery; however, there is no significant improvement in packet delivery if the number of retransmissions is increased from 2 to 7

Performance evaluation with different backoff ranges [39]BEProvide priority-based QoS by assigning different BE values to different applications

Priority-based delay mitigation for event monitoring [40]MAC frame modification, CCACollision avoidance-based priority mechanism by using one time CCA

Priority-based service differentiation scheme [41]CWContention Windows Differentiation (CWD) mechanism is proposed

MAC protocol implementation [42]Superframe order (SO)Conduct a study by applying different values of superframe order (SO); results show that high values of SO provide high throughput, whereas low SO values result in less delay

Performance evaluation with backoff [43, 44]BEPropose an Adaptive Backoff Exponent (ABE) mechanism which reduces the devices probability to reduce collisions

Comprehensive simulation study for CSMA/CA [45]BEHigher values of macMinBE and macMaxBE lead towards higher packet delivery ratios; however, the delay will be increased as well