Is Enterprise Service Bus (ESB) Obsolete After Microservices?

Most organizations are adopting and sunsetting components in their IT infrastructure to meet the business needs. To increase the business values, explore new opportunities in the market requires digital transformation for any organization. While doing digital transformations, several applications are integrating with different integration methodologies and different architecture patterns. Service-Oriented Architecture (SOA) emerged into the industry for more than a decade. Enterprise Service Bus (ESB) became the most popular middleware pattern/integration patterns to solve most of the integration problems in monolithic applications. ESB's main features include message transformation, protocol conversion, service orchestration, and payload enrichment. These features are readily available in all majorities of ESB implementations from different vendors. The features help the solution to be integrated with different types of systems within the Enterprise seamless.

Advantages and disadvantages of ESB’s solutions are described below:

Nowadays, Microservices Architecture (MSA) is more prevalent than Enterprise Service Bus (ESB). Like ESB, microservices architectures made up of loosely coupled and reusable components. Microservices are an advantage on top of ESB due to deploying on cloud platforms. Teams can code and update code more effectively due to microservices are dedicated cloud-native architecture approach. Microservices use different stacks for different microservices and scale independently, reducing the waste and cost associated with having to scale entire applications as like in ESB architecture. Therefore, compared to ESB, microservices are more fine-grained control and higher scalability.

Advantages and disadvantages of microservices solutions described below:

Both the ESB and Microservice approaches have their advantages and disadvantages. Choosing the best solution depends on how large and diverse the new application environment. Microservices give added advantages compared to ESB’s due to the support of the latest cloud deployment platforms. Larger, more diverse environments choose ESB solution, whereas Smaller environments, including web and mobile applications, would choose microservices architecture.

Here are factors you must consider when choosing the right solution for an integration architecture:

• Types of services to be integrated
• Communication protocols/messaging format support
• Transport protocol support
• Routing and transformations
• Performance and quality of services
• Cloud capability
• Security requirements
• Inter-dependencies of services
• Team members Skillsets

The requirements should be carefully analyzed with the growth of the organization’s digital transformation strategy in the next 5–10 years. Sometime a hybrid approach would also work if the organization business goals can be achieved.  As per the new trends, the ESB market is to be declining. ESB’s are still using to integrate Legacy applications. The legacy applications are still in the market for the next 5-10 years till the Digital transformation completes. With the rise of microservices, enterprise solutions have below paths to consider.

• Monolithic Application – Monolithic applications connecting using ESB’s
• Hybrid ESB - Mix of monolithic applications and cloud-based microservices connected using ESB’s and iPaas (integration Platform as a Service)
• Microservices Applications – Complete microservices architecture.

Concludes that ESB’s still exists in the next 5-10 years till all the monolithic / legacy applications moved to microservices. If the Enterprise runs smoothly with the existing ESB, there is no point in embracing the microservice revolution. You want to increase business agility, save money and time, then update IT infrastructure with new cloud-native platforms.