As part of the design process to produce a software system for addressing the analysis process stack , we utilized a simplified model, whereby the various capabilities were classified into one of three layers. While it might have been intuitive to identify a separate software model layer with each of the boundaries in the process stack, in reality, some of the types of processing employed by adjacent layers have similar requirements. From this perspective, rather than representing the process stack with 5 layers, a simplified version containing 3 layers (blue/green, yellow, and red) can be used.
An alternate way of interpreting the 3-Layer version is that each layer is based on the nature of the processing required to provide a given capability. Each of the three layers (bottom, middle and top) be characterized by the nature of data they operate on and the level of abstraction created by the technology.
The purpose of the bottom layer is to interact with the external data and produce corresponding entries in the knowledgebase. Functions such as feature extraction, detection , and identification reside in this layer.
The middle layer is where relationships are identified. Processing here operates only on information present in the knowledgebase, either inferred or directly translated there by the bottom layer. Functions such as clustering and classification occur in the middle layer.
Finally, the responsibility of the top layer is to conceptualize the situation in more of an abstract way than that provided by the middle layer. Like the middle layer, it also operates exclusively on information in the knowledgebase. But unlike the middle layer, the nature of the processing is more abstract and specific to a particular domain model. Functionality such as sensemaking , decision-support and behavior simulation reside in the top layer.
In order to identify appropriate technologies to address the requirements of each of the three model layers, it is important to identify their functionality and data characteristics.
Bottom layer | Middle Layer | Top layer