Chapter 5: DATA FLOW ARCHITECTURES - Coggle Diagram
Chapter 5: DATA FLOW ARCHITECTURES
5.1 Batch Sequential
each data tranformation subsystem or module cannot start its process until its previous subsystem completes its computation
VALIDATE: the transaction requests
(insert, delete, and update) in their totality
SORT: all transaction records in an ascending order on the primary key of data records
UPDATE: The transaction update module updates the master file with the sorted transaction requests, and then the report module generates a new list.
Applicable domains of batch sequential architecture:
Data are batched
Intermediate file is a sequential access file.
Each subsystem reads related input files and writes output files
Simple divisions on subsystems
Each subsystem can be a stand-alone program working on input
data and producing output data.
Implementation requires external control.
It does not provide interactive interface.
Concurrency is not supported and hence throughput remains low
5.2 Pipe and Filter Architecture
decomposes the whole system into components of data source, filters, pipes, and data sinks
three ways to make the data flow:
Push only (Write only)
A data source, filter may push data in a downstream.
Pull only (Read only)
A data sink, filter may pull data from an upstream.
A filter may pull data from an upstream and push transformed
data in a downstream.
There are two types of filters
pulls in data and pushes out the transformed data
lets connected pipes push data in and pull data out
Applicable domains of pipe and filter architecture:
The system can be broken into a series of processing steps over
data streams and at each step filters consume and move data incrementally.
The data format on the data streams is simple, stable, and adaptable if necessary.
Significant work can be pipelined to gain increased performance.
Producer or consumer-related problems are being addressed.
It is not suitable for dynamic interactions
A low common denominator is required for data transmission in
the ASCII formats
Overhead of data transformation among filters such as parsing is
repeated in two consecutive filters.
5.3 Process Control Architecture.
decomposes the whole system into subsystems (modules) and connections between subsystems.
Applicable domains of process control architecture:
Embedded software systems involving continuing actions
Systems that need to maintain an output data at a stable level
The system can have a set point—the goal the system will reach at its operational level.
It offers a better solution to the control system where no precise
formula can be used to decide the manipulated variable.
The software can be completely embedded in the devices.