The use of sensor networks has been proposed for military surveillance and environmental monitoring applications. These systems could deploy heterogeneous collections of sensors capable of observing and reporting on various dynamic properties of their terrain in a timely manner. Data reports from areas of the sensor network will be aperiodic and diverse, carrying a range of application specific data and requiring delivery in accordance with specified deadlines. Such systems will suffer bandwidth and throughput constraints that limit the quantity of information transferred from point to point. Mechanisms to perform data centric aggregation utilizing application specific knowledge provide a means to augmenting throughput, but are inherently limited due to their reliance on application specific and data-centric decision making. We therefore propose a novel aggregation scheme that performs application independent data aggregation in a time sensitive manner. Our work isolates aggregation decisions into a module that resides between the network and data link layer protocols of the communication stack and does not require any modifications to currently existing MAC and Network layer protocols. At this layer we take advantage of queuing delay and the broadcast nature of wireless communication to concatenate network payloads into an aggregate MAC layer payloads. We therefore only incur the cost of channel contention and back off once per aggregate, increasing throughput and reducing end to end transmission time without imposing any significant communication overhead. We call our protocol AIDA (Application Independent Data Aggregation).
Figure 1: Architectural Designs
The basic design of AIDA is shown in Figure 2. We separate AIDA functionality into two components. One is the functional unit that aggregates and de-aggregates network packets (units). The other is the AIDA Aggregation Control Unit, employed to adaptively control timer settings and fine-tune the desired degree of aggregation. For more detail see PDF
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Figure 2: Components In AIDA
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