The organizational structure – or architecture – of software anticipates common operational issues throughout the development lifecycle. Software architecture patterns use clearly defined and reusable components to support desired system outcomes. Developers and engineers can build complex software on patterns that fit with project goals.
Decades of software development have resulted in a rich library of software architecture patterns. Choosing a pattern depends on the program’s desired outputs, level of interactivity, and complexity. The following patterns are frequently cited by software engineers as essential tools in their kits.
Layered Architecture Pattern
The layered software architecture pattern is frequently used because of its simple design. Common functionalities are combined into independent layers. The typical version of this pattern includes at least four layers with variations based on software complexity:
- Presentation
- Business
- Persistence
- Database
Each layer communicates with the next layer upon request but is not dependent on others for its operation. A request at the presentation layer works its way to the database layer and returns in reverse order with the required information. A layered architecture pattern is ideal for development projects with limited budgets and time because of its intuitive design.
The benefits of this pattern go beyond budget-friendly simplicity. Software problems are easy to identify because similar functions are found within the same layers. Engineering teams easily customize layers with new features as additional program functionality is required.
Client-Server Pattern
Software engineers sometimes need architecture patterns that provide direct lines between clients and data. The client-server - or two-tiered- pattern accommodates multiple users accessing a centralized resource. This structure works in the following way:
- The user sends a request to the server via a client like a browser
- The server accesses data to fulfill the specific requirements of this request
- Data at both ends of this request may be encrypted and authenticated
The client-server pattern provides sound foundations for software and systems with high-volume usage. The Internet represents a global example of the client-server pattern in action. This software architecture pattern is also used for banking systems, email services, and productivity software.
Systems built on the client-server pattern support distributed user bases at local, regional, and global scales. Engineers anticipate potential bottlenecks created by peak periods of demand with this design scheme. The simplicity of client-server architecture means that development resources can be allocated to advanced features.
Event-Driven Architecture Pattern
Engineering teams need a pattern for complex interactions with multiple possible outcomes. E-commerce websites use event-driven architecture to streamline their interactions with users. This pattern processes events like adding an item to a cart or requesting a return label in the following order:
- Data from a user event are passed to an event router for assignment;
- The router assigns data to the event consumer for processing;
- Event consumers like customer service teams and data warehouses resolve requests.
Developers and engineers favor this software architecture pattern because of its modular nature. For example, an online marketplace can add new event consumers without significantly changing its user interface. Each expansion requires new router rules and backend adjustments that are achievable without system outages.
Event-driven architecture recognizes the need for system-agnostic processes going forward. Global users want the same experience of a system whether they are using an Apple iPhone, a Chromebook, or a desktop. This pattern supports user interfaces of similar quality no matter the user’s location or hardware.
Microservices Architecture Pattern
NGINX found that 44% of surveyed developers used microservice architecture with another 24% considering its use. The trend toward microservices has been driven by startups and small companies in need of agile architecture. Engineers have added microservices patterns to their repertoires because they are among the most agile patterns.
This software architecture pattern pools multiple microservices within the same system. Each microservice serves a narrowly defined purpose and microservices work with each other as necessary. Users need not worry about sorting through apps or tools as gateway APIs are designed to access the appropriate microservices.
Microservice architecture is used for cloud computing and systems with complex data processing requirements. For example, a payment processing system built on microservices can handle multiple types of transactions from millions of users without slowing down. Engineers can experiment with new microservices without taking systems offline because surrounding services are independent.
Peer-to-Peer Architecture Pattern
Another decentralized software architecture available to software engineers is the peer-to-peer pattern. A peer-to-peer system is built on the concept that each user - or peer - acts as a client as well as a server. Users exchange data with each other without an intermediary filter and interactions are regulated by the availability of peers.
A significant benefit of the peer-to-peer pattern is that it lacks a single chokepoint. The absence of routers and APIs leads to quicker downloads as well as greater freedom to explore available data. Additional benefits of peer-to-peer architecture include:
- Resilience to faults because peers step in to cover inaccessible servers
- Minimal upfront and hosting expenses as clients double as servers
- Systems with large numbers of peers ensure high bandwidth
Peer-to-peer concepts have been used for online gaming and file-sharing services for decades. The most recent applications of this software architecture pattern involve cryptocurrencies like Bitcoin. Peer-to-peer architecture works well for systems where users need low barriers to interaction with each other.
Become an Expert in Software Architecture Patterns at Baylor University
You can learn to effectively deploy these patterns in Baylor University’s Online Masters of Computer Science degree programs. Students in the Software Engineering track explore the intricacies of software design with experienced faculty. This degree was developed with Association for Computer Machinery standards for ethics and problem-solving in mind.
Incoming students are not required to hold undergraduate degrees in computer science for admission. This program accepts applicants with other STEM degrees along with programming knowledge. Advanced coursework on the following topics provides important foundations for future engineers:
- Advanced Object-Oriented Development
- Advanced Software Engineering
- Distributed Systems
- Software Verification & Validation
Degree candidates learn more than how to use software architecture patterns at Baylor University. The university imbues its students with the spirit of innovation necessary for the challenges of tomorrow. U.S. News & World Report recognized this impact by ranking Baylor No. 34 in its Most Innovative Schools ranking.
Find out more about how Baylor University can elevate your software engineering career by requesting a program brochure today.
