Middleware is software that provides common services and capabilities to applications outside of what’s offered by the operating system. Data management, application services, messaging, authentication, and API management are all commonly handled by middleware.
Middleware helps developers build applications more efficiently. It acts like the connective tissue between applications, data, and users.
For organizations with multi-cloud and containerized environments, middleware can make it cost-effective to develop and run applications at scale.
The origin of middleware
The term middleware first appeared in a report following the 1968 NATO Software Engineering conference in Garmisch-Partenkirchen, Germany. The conference sought to define the field of software engineering, and included software design, production, and distribution.
As a broad category, middleware can encompass everything from web servers to authentication systems to messaging tools. Here are a few of the common use cases for middleware in modern development.
New application development
Middleware can support modern and popular runtimes for a variety of use cases. Developers and architects can work with agility across platforms, following sets of foundational runtimes, frameworks, and programming languages. Middleware can also deliver commonly used functions such as web servers, single sign-on (SSO), messaging, and in-memory caching.
Optimization of existing applications
Middleware can help developers transform legacy monolithic applications into cloud-native applications, keeping valuable tools active with better performance and more portability.
Middleware integration tools connect critical internal and external systems. Integration capabilities like transformation, connectivity, composability, and enterprise messaging, combined with SSO authentication, make it easier for developers to extend capabilities across different applications.
Application Programming Interfaces (APIs)
Many middleware services are accessed through APIs, which are sets of tools, definitions, and protocols that allow applications to communicate with each other. APIs make it possible to connect completely different products and services through a common layer.
While APIs are one way to share data between applications, another approach is asynchronous data streaming. This replicates a data set in an intermediate store, where the data can be shared among multiple applications. One popular open source middleware tool for real-time data streaming is Apache Kafka.
Intelligent business automation
Middleware can help developers, architects, IT, and business leaders automate manual decisions. Automation can improve resource management and overall efficiency.
For all the benefits cloud-native development provides, it also brings added complexity. Applications can be deployed across multiple infrastructures, from on-premises systems to public clouds. Architectures can vary widely. Developers are juggling multiple tools, languages, and frameworks. And the pressure is on to do more in less time and at a lower cost.
Organizations turn to middleware as a way to manage this complexity and to keep application development quick and cost-effective. Middleware can support application environments that work smoothly and consistently across a highly distributed platform.
Build here. Deploy there. It works the same, thanks to the middleware beneath the applications.
Modern business apps are engineered to run at scale, on premises, and across clouds. To build them, developers need an application environment with unified foundational capabilities. Middleware is the key to assembling such an environment.
We can think of these capabilities in 4 layers, plus tooling:
The container layer
The runtimes layer
This layer contains the execution environments for custom code. Middleware can provide lightweight runtimes and frameworks for highly distributed cloud environments such as microservices, in-memory caching for fast data access, and messaging for quick data transfer.
The integration layer
Integration middleware provides services to connect custom and purchased apps, as well as Software-as-a-Service (SaaS) assets through messaging, integration, and APIs to form functioning systems. It can also deliver in-memory database and data cache services, data/event streaming, and API management.
The process automation and decision management layer
This final layer of development middleware adds critical intelligence, optimization and automation, and decision management.
In addition to these 4 layers of middleware there’s application development tooling. This allows teams to build applications using preset templates and containers, and facilitates efficient code sharing and joint development. Tooling supports a consistent and coherent application development and delivery experience on-premises and cloud.