Architecture
System Category Consists of
A set of components(eg: a database, computational modules) that
will perform a function required by the system.
The set of connectors will help in coordination, communication,
and cooperation between the components.
Conditions that defines how components can be integrated to
form the system.
Semantic models that help the designer to understand the overall
properties of the system.
The use of architectural styles is to establish a structure for all the
components of the system.
Taxonomy of Architectural Styles
1] Data centered architectures :
A data store will reside at the center of this architecture and is
accessed frequently by the other components that update, add,
delete, or modify the data present within the store.
The figure illustrates a typical data-centered style. The client
software accesses a central repository. Variations of this approach
are used to transform the repository into a blackboard when data
related to the client or data of interest for the client change the
notifications to client software.
This data-centered architecture will promote integrability. This
means that the existing components can be changed and new
client components can be added to the architecture without the
permission or concern of other clients.
Data can be passed among clients using the blackboard
mechanism.
Advantages of Data centered architecture:
Repository of data is independent of clients
Client work independent of each other
It may be simple to add additional clients.
Modification can be very easy
Data centered architecture
2] Data flow architectures:
This kind of architecture is used when input data is transformed
into output data through a series of computational
manipulative components.
The figure represents pipe-and-filter architecture since it uses
both pipe and filter and it has a set of components called filters
connected by lines.
Pipes are used to transmitting data from one component to the
next.
Each filter will work independently and is designed to take data
input of a certain form and produces data output to the next filter
of a specified form. The filters don’t require any knowledge of the
working of neighboring filters.
If the data flow degenerates into a single line of transforms, then
it is termed as batch sequential. This structure accepts the batch
of data and then applies a series of sequential components to
transform it.
Advantages of Data Flow architecture:
It encourages upkeep, repurposing, and modification.
With this design, concurrent execution is supported.
Disadvantage of Data Flow architecture:
It frequently degenerates to batch sequential system
Data flow architecture does not allow applications that require
greater user engagement.
It is not easy to coordinate two different but related streams
Data Flow architecture
3] Call and Return architectures
It is used to create a program that is easy to scale and modify. Many
sub-styles exist within this category. Two of them are explained
below.
Remote procedure call architecture: This components is used to
present in a main program or sub program architecture
distributed among multiple computers on a network.
Main program or Subprogram architectures: The main program
structure decomposes into number of subprograms or function
into a control hierarchy. Main program contains number of
subprograms that can invoke other components.
4] Object Oriented architecture
The components of a system encapsulate data and the operations
that must be applied to manipulate the data. The coordination and
communication between the components are established via the
message passing.
Characteristics of Object Oriented architecture:
Object protect the system’s integrity.
An object is unaware of the depiction of other items.
Advantage of Object Oriented architecture:
It enables the designer to separate a challenge into a collection of
autonomous objects.
Other objects are aware of the implementation details of the
object, allowing changes to be made without having an impact on
other objects.
5] Layered architecture
A number of different layers are defined with each layer
performing a well-defined set of operations. Each layer will do
some operations that becomes closer to machine instruction set
progressively.
At the outer layer, components will receive the user interface
operations and at the inner layers, components will perform the
operating system interfacing(communication and coordination
with OS)
Intermediate layers to utility services and application software
functions.
One common example of this architectural style is OSI-ISO (Open
Systems Interconnection-International Organisation for
Standardisation) communication system.
Layered architecture
