Your ERP doesn’t talk to your CRM. Your HR data sits isolated in a corner, cut off from everything else. And every time a business team adds a new SaaS tool, that’s one more integration to patch together. Welcome to the reality of the modern IT system, where the average enterprise juggles 897 different applications (source: APPSeCONNECT). This is where middleware comes in.
What exactly is middleware?
The word comes from « middle » and « software ». In practice, middleware is software that sits between the applications, databases, and operating systems of an information system, allowing them to communicate with each other (source: IBM).
It’s often described as the cement of a building or the nervous system of an organization. Without it, each application stays in its silo, speaks its own language, and ignores the others. With it, the whole forms a coherent system where information flows, processes chain together, and teams stop wasting time copying data from one tool to another.
The term first appeared officially at a NATO software engineering conference in 1968, then took hold in the 1980s as a way to connect new applications to legacy systems (source: Wikipedia). Its role has only grown since.
Why your IT system needs it
The reason is simple: the modern IT system has become a patchwork. ERP, CRM, marketing automation tools, HR platforms, specialized business applications, cloud services, legacy databases… The average enterprise now uses 897 applications, and 46% of large organizations exceed 1,000 (source: ONEiO Cloud). More worrying still, 71% of those applications remain unintegrated, which multiplies manual data entry, errors, and data silos.
Without middleware, each new application requires building a custom connector. Multiplied across dozens of tools, the cost explodes: Gartner estimates that enterprises spend 30 to 40% of their IT budget managing the complexity created by unintegrated applications (source: APPSeCONNECT). Middleware changes the equation by providing a single abstraction layer: build once, connect everywhere.
The market reflects this need. Enterprise application integration is expected to reach $26.8 billion in 2026, growing at 16.5% per year (source: The Business Research Company). Not a passing trend, but a structural answer to a problem that keeps getting worse.
The main families of middleware
Not all middleware does the same thing. Several broad categories are traditionally distinguished (source: AWS). Message Oriented Middleware (MOM) passes messages between applications asynchronously, much like a queue (Apache Kafka and RabbitMQ are popular examples). Enterprise Application Integration (EAI) middleware connects multiple heterogeneous systems through a common hub, historically through an Enterprise Service Bus (ESB).
iPaaS (Integration Platform as a Service) is the cloud native version of EAI, integrating applications across hybrid environments. It is now the most dynamic segment of the market, expected to exceed $17 billion by 2028 according to Gartner (source: ONEiO Cloud). API middleware, or API Gateways, handles API requests between applications, enforces security policies, and monitors performance. This segment alone accounts for 28.7% of the integration market in 2026 (source: Persistence Market Research). Finally, platform middleware (application servers, web servers, content management systems) provides a common runtime foundation for applications.
This diversity is no accident: each use case has its own constraints. But they all share the same fundamental mission: making things talk that weren’t designed to talk to each other.
The limits of traditional middleware
Middleware isn’t a silver bullet. Three blind spots keep coming up.
First, data duplication. Most traditional middleware works by copying data from one system to another, or by centralizing it in an intermediate hub. The result: the same information exists in multiple copies, sometimes with diverging versions, and each one is another attack surface or potential leak.
Second, complexity. 45% of organizations cite middleware complexity as a barrier, and 39% report integration delays caused by interoperability issues (source: Business Research Insights). The bigger the IT system grows, the more the middleware itself becomes a system to maintain, with its own dependencies and its own potential failure points.
Third, sovereignty. Many integration middleware products today are American SaaS services, subject to the Cloud Act. The data flowing through them can legally be requested by U.S. authorities, even if the client is European. For regulated sectors (healthcare, defense, finance, public sector), this becomes a deal breaker. As we explained in our article on digital sovereignty, the provider’s nationality outweighs the location of the servers.
What if middleware didn’t need to store anything to work?
The historical logic of middleware rests on one rarely questioned assumption: to move data around, you first have to capture it, transform it, and sometimes store it. That’s exactly what creates the complexity, the duplication, the exposure.
iD4Connect takes a different approach: middleware that processes data during transit, without ever storing or duplicating it. Each DataCell acts as an intelligent processing unit (cleaning, transformation, enrichment, routing) that runs on the data as it passes through, then releases it. Nothing persists, nothing accumulates.
The orchestration of these DataCells, structured as a DataGraph, makes it possible to build complex flows between any applications, in any environment: on premise, cloud, or hybrid. The Universal Connector handles multisource ingestion across all standard protocols (JDBC, ODBC, MQTT, Kafka, REST…), without forcing its own format.
The benefit for the IT system is threefold: the exposure surface is reduced to zero since the middleware never stores the data, sovereignty is guaranteed by the architecture itself (European design, execution within the client’s perimeter), and operating costs stay predictable.
In 2026, the real question may no longer be « which middleware to choose, » but how to make your IT system talk to itself without turning it into a graveyard of copies.
