Background: The main requirement of Wireless Body Area Network (WBAN) is on-time
delivery of vital signs that are sensed through the delay-sensitive biological sensors that are implanted
in the body of the patient being monitored by the central gateway. The Medium Access Control
(MAC) protocol standard IEEE 802.15.4 supports real-time data delivery through its unique feature
called Guaranteed Time Slot (GTS) under its beacon-enabled mode. This protocol is considered suitable
for the WBAN Scenario. However, as per the standard, IEEE 802.15.4 uses a simple and straightforward
First Come First Served (FCFS) mechanism to distribute GTS slots among the contender
nodes. This kind of blindfolded allocation of GTS slots results in poor utilization of bandwidth and
also prevents the delay-sensitive sensor nodes from effectively utilizing the contention-free slots.
Objective: The main objective of this work is to provide a solution for the unfair allocation of GTS
slots in the beacon-enabled mode of the IEEE 802.15.4 standard in WBAN.
Methods: We propose a Rational Allocation of Guaranteed Time Slot (RAGTS) protocol that distributes
the available GTS slots based on the delay-sensitivity of the contender nodes.
Results: A series of simulation experiments has been performed to assess the performance of our
proposed RAGTS protocol. The simulations capture the dynamic nature of the real-time deadlines associated
with sensor traffic. Through simulations, we show that our proposed RAGTS protocol appears
to be more stable in terms of various performance metrics than that of the FCFS nature of the
GTS allocation technique.
Conclusion: In this article, we introduced the RAGTS scheme that enhances the real-time traffic feature
of the beacon-enabled mode of IEEE 802.15.4 MAC.