Enterprise Service Bus
An enterprise service bus (ESB) is an architecture that allows communication between different environments, such as software applications. However, as there is no set industry definition for what enterprise service buses are it can result in different understandings of precisely what is meant when an ESB is being referred to.
The concept behind a bus is that different software components (known as services) that run independently can integrate and communicate with each other. This happens as each application talks to the bus, which modulates the communication, ensuring it arrives in the right place, saying the right thing in the right way. A simplistic analogy would be an automatic translation app that allows everyone to talk in their own language, but the listener would hear it perfectly in theirs.
The integration of ESB with open source integration platforms has enabled it to reach a very wide range of users. Extending ESB to the many has allowed organizations around the world to improve the speed of their activities.
ETL vs. ESB
ETL (extract, transform, load) tools are a huge part of data warehousing and integration. It is common for them to be seen in competition with ESB architecture when it comes to data integration and improving connectivity. However, as can be seen from many systems, such as SnapLogic, ETL and ESB can actually help each other. This is because of their complementary strengths, ETL in moving large amounts of data and ESB in addressing real-time transactional data.
As software applications grew, it became necessary to abandon point-to-point communication between nodes, which was not scalable. So a more flexible messaging system was required, which was ESB. This is now also being challenged in itself in an ESB vs. Microservices competition, with the latter becoming the new standard for messaging architecture within an application.