Software architecture types
All the software developers can follow some of the architecture patterns to develop a new software. So, Let’s Discuss about what is software architecture and What are different varieties of Architectural patterns followed by their pros and cons?
What is an architectural pattern in software? A blueprint or structure can be followed by any software developer to create a new software system. An architectural pattern provides guidelines and rules for organizing the relationships and functions of defined subsystems, as well as the high-level structure and organization of the system.
The behavioral components, organizational structure, and assembly of these components into complex subsystems are all included in software architecture.
A software architecture developed in that way, to ensure that system meets functional and nonfunctional requirements.
Software architecture offers advantages such as improved efficiency, productivity, speed, cost optimization, and better planning.
Different types of Software architectural patterns:
Layered architecture: (N-tier architecture)
As its name mentioned, it is a layered, components get organized into horizontal layers by holding a specific performance for every layer.
Most of the cases there is no specification for total number of layers present in the pattern. A layer presentation typically has four layers: presentation, business, persistence, and database.
Where the “presentation layer” will be responsible for all browser communication and user interface logic, the “business layer” will execute specified business rules for a request, the “persistence layer” is responsible for handling functions and data persistence, and the “database layer” provides the ability to store and retrieve data.
Presentation layer (also known as UI layer)
Business layer (also known as domain layer)
Persistence layer (also known as service layer)
Data access layer (also known as persistence layer).
Popular frameworks like Java EE utilized this architecture pattern.
PROS: Modularity, Complexity, Scalability, Performance Overhead, Reusability, Reusability, Rigid Structure.
CONS: Flexibility, Duplication of Logic, Maintainability, Difficulty in Testing, Performance, Tight coupling risks if layer boundaries aren’t well-defined.
Client-Server Architecture:(master-slave)
As the name spells, client and server are two main roles in this architecture. CSA Separates applications into clients (user interfaces) and servers (data processing) to manage data sharing and user interactions. This pattern Ideal for distributed systems like web-based services.
The client is responsible for initiating communication with the server and sending a request. The server, on the other hand, listens for incoming requests from clients, processes them, and returns a response.
When multiple requests want to be processed from different clients at the same time, the server uses master-slave pattern. So, when requests are received by the Master, it creates different slaves to complete the requests individually and resume request listening.
Email System, Online Gaming, Remote File Storage are the cases where we can majorly use Client-server architecture.
PROS: Scalability, Cost, Single Point of Failure, Centralized Data, Network Dependency, Resource Sharing.
CONS: Security, Complexity, Centralized Management, Limited Scalability, Reliability, Security Concerns.
Event-Driven Architecture: (action-driven)
Here, Events we can considered as actions i.e., when something happens to the application system an event has occurred. EDA Used in real-time systems and graphical user interfaces. In this, different Software components relate to each other using events rather than requests or responses.
The pub/sub model is a flexible pattern for messaging enabling distributed components of the software to asynchronously interact with each other.
This approach allowed Amazon to build loosely coupled systems to handle large-scale traffic and respond to events in real-time.
A good example that uses event-driven architecture is an e-commerce site.
Overall, while event-driven architecture offers many benefits, it also comes with its own set of challenges that need to be carefully considered and addressed during implementation.
PROS: Scalability, Complexity, Flexibility, Event loss, Responsiveness
CONS: Debugging and monitoring, Fault tolerance, Performance overhead, Real-time processing, Resource management
Pipe and Filter Pattern:
In this architecture, components referred to as filters and pipes are connected to these filters. Here, streaming of data will be done in unidirectional flow.
The chain of processing data takes place where the pipes transmit data to the filters, and the result of one filter becomes the input for the next filter. The function of this architecture is to break down significant components/processes into independent and multiple components that can be processed simultaneously.
PROS: Modularity, Complexity, Reusability, Performance, Scalability.
CONS: Data flow control, Maintainability, Data consistency, Testability, Limited interaction.
Microkernel:
A microkernel is a minimalistic approach to kernel design that aims to keep the kernel as small as possible, delegating most tasks to user space processes.
A core system and plug-in modules are two types of components. While the core system works on minimal functionality to keep the system operational, the plug-in modules are independent components with specialized processing.
If we take a business application’s perspective, the core system can be defined as general business logic without the custom code for special cases, special rules, or complex conditional processes. On the other hand, the plug-in modules are meant to enhance the core system to produce additional business capabilities.
PROS: Modularity, Performance, Reliability, Complexity.
CONS: Flexibility, Resource Usage, Isolation, Device Driver Performance.
Microservices:
The microservices architecture pattern is an alternative to monolithic applications and service-oriented architectures. The components are deployed as separate units through an effective, streamlined delivery pipeline.
Owing to its decoupled and independent characteristics, the components are accessed through a remote access protocol. Moreover, the same components can be separately developed, deployed, and tested without interdependency on any other service component.
Netflix is one of the early adopters of the microservice architecture pattern.
This pattern is Common in cloud services.
PROS: Scalability, Complexity, Flexibility, Increased Overhead, Fault Isolation, Data Management, Continuous Deployment.
CONS: Testing Complexity, Improved Maintainability, Deployment Complexity, Technology Diversity, Security.
Space-Based Architecture Pattern:
The space-based pattern comprises two primary components — a processing unit and a virtualized middleware.
The processing unit contains portions of application components, including web-based components and backend business logic.
The virtualized-middleware component contains elements that control various aspects of data synchronization and request handling.
While smaller web applications could be deployed in a single processing unit, the larger applications could split the application functionality into multiple processing units to avoid functional collapse.
PROS: Scalability, Complexity, Flexibility, Consistency, Performance, Cost.
CONS: Fault Tolerance, Latency, Loose Coupling, Data Partitioning, High Availability, Deployment Complexity.
Broker Architecture Pattern:
Clients, servers, and brokers are three major components of the broker pattern. The broker is responsible for all the coordination and communication among the components. When clients request a service from the broker, the broker redirects them to a suitable service category for further processing.
This architecture pattern separates all communication-related code into layers from the application, allowing applications to run on distributed or single computers.
Used in message broker software such as Apache ActiveMQ, Apache Kafka, RabbitMQ, and JBoss Messaging.
PROS: Decoupling, Single Point of Failure, Scalability, Performance Bottleneck, Reliability, Complexity.
CONS:
Scalability
Performance Bottleneck
Reliability
Complexity
Flexibility
Latency
Security
Cost
Monitoring and Management
Configuration and Maintenance
· Peer-to-Peer Architecture Pattern:
In the peer-to-peer architectural pattern, individual components are called peers. A peer can act as a client, a server, or both and change its role dynamically over time.
As a client, a peer can request service from other peers, and as a server, a peer can provide services to other peers.
The significant difference between peer-to-peer and client-server architecture is that each computer on the network has considerable authority and the absence of a centralized server. Its capacity increases as more and more computers join the network.
PROS
CONS
Decentralization
Security Concerns
Scalability
Performance
Resource Sharing
Network Overhead
Resilience
Complexity
Cost-Effectiveness
Quality of Service
Anonymity and Privacy
Legal and Regulatory Issues
An excellent example of a peer-to-peer architecture pattern would be file-sharing networks like Skype, BitTorrent, and Napster.
These architectural patterns provide a structured approach for organizing components, defining interactions, and establishing a system’s fundamental layout.