System integration is the bringing together of the component subsystems into one system and ensuring that the subsystems function together as a system. In information technology, systems integration is the process of linking together different computing systems and software applications physically or functionally, to act as a coordinated whole.

The system integrator brings together discrete systems utilizing a variety of techniques such as computer networking, enterprise application integration, business process management or manual programming.

Methods of integration
Vertical Integration (as opposed to "horizontal") is the process of integrating subsystems according to their functionality by creating functional entities also referred to as silos. The benefit of this method is that the integration is performed quickly and involves only the necessary vendors, therefore, this method is cheaper in the short term. On the other hand, cost-of-ownership can be substantially higher than seen in other methods, since in case of new or enhanced functionality, the only possible way to implement (scale the system) would be by implementing another silo. Reusing subsystems to create another functionality is not possible.

Star Integration or also known as Spaghetti Integration is a process of integration of the systems where each system is interconnected to each of the remaining subsystems. When observed from the perspective of the subsystem which is being integrated, the connections are reminiscent of a star, but when the overall diagram of the system is presented, the connections look like spaghetti, hence the name of this method. The cost varies due to the interfaces which subsystems are exporting. In a case where the subsystems are exporting heterogeneous or proprietary interfaces, the integration cost can substantially rise. Time and costs needed to integrate the systems increase exponentially when adding additional subsystems. From the feature perspective, this method often seems preferable, due to the extreme flexibility of the reuse of functionality.

Horizontal Integration or Enterprise Service Bus (ESB) is an integration method in which a specialized subsystem is dedicated to communication between other subsystems. This allows cutting the number of connections (interfaces) to only one per subsystem which will connect directly to the ESB. The ESB is capable of translating the interface into another interface. This allows cutting the costs of integration and provides extreme flexibility. With systems integrated using this method, it is possible to completely replace one subsystem with another subsystem which provides similar functionality but exports different interfaces, all this completely transparent for the rest of the subsystems. The only action required is to implement the new interface between the ESB and the new subsystem.

The horizontal scheme can be misleading, however, if it is thought that the cost of intermediate data transformation or the cost of shifting responsibility over business logic can be avoided.

A common data format is an integration method to avoid every adapter having to convert data to/from every other applications' formats, Enterprise application integration (EAI) systems usually stipulate an application-independent (or common) data format. The EAI system usually provides a data transformation service as well to help convert between application-specific and common formats. This is done in two steps: the adapter converts information from the application's format to the bus's common format. Then, semantic transformations are applied on this (converting zip codes to city names, splitting/merging objects from one application into objects in the other applications, and so on).


Companies are building more BI capabilities into their business applications because it's becoming easier to do so. These applications and BI tools are becoming Web-based so it's easier to build in URLs, cookies and single sign-on to pass information between BI apps and business apps.

Vendors are also embedding BI capabilities into business processes. BI integrates business activity monitoring (BAM) capabilities and BI components to capture transaction and workflow data across several applications and business units. This capability can bring up information such as recent credit card transactions or buying history in a CRM application while a representative is processing an order, for example.

Still, to effectively marry BI with business applications and processes, the CIO needs to bring together the application and BI development teams so they get to the point of cross development, where the BI developers -- who work with business users day in and day out -- share what they learn with the business application developers.

The key to implementing BI correctly is having a clear understanding of why you’re doing so.

1. Don’t implement BI – implement an end-goal
One of the reasons that BI is notoriously difficult to get right is the fact that businesses often undertake BI without a well-defined idea of what ‘right’ will mean.

ERP systems capture an incredible amount of transactions and business data, and the role of BI is to convert these records into information that can be used by decision makers.

It’s vital to remember that the purpose of BI is to produce information and insight. Thus, deciding what insight your business needs is the first step to implementing BI.

Good questions to ask are: which business areas are you going to analyse? What are the important Key Performance Indicators? How will decision makers react to the insight your solution produces and what specific outcomes will it achieve?

Understand that BI will not solve problems in its own right. To be successful, you need to know your business and where you want to take it, then make the turn to BI.

2. Don’t delegate success
The best BI integrations emerge from deep understandings of business operations.

While BI vendors will do their utmost, this is the main reason that you shouldn’t rely on your vendor to create project success.

Instead, have someone from your own organisation at the helm to drive the project.

3. Don’t go it alone
BI is a complex arena, and multiple solution types, software packages and integration hurdles make implementation a difficult assignment.

In the same way that a maiden skipper wouldn’t sail for New Zealand without an experienced crew, those responsible for BI integrations can avoid disaster by having practiced help on deck.

Ideally, your BI vendor will be experienced not only in the particular product you’re going to implement, but also in your industry. Because BI is about business improvement, hunting for a vendor with previous exposure to your industry means that the project is more likely to be informed by relevant assumptions about business processes and KPIs from the start – making it that much more likely to succeed.

4. Avoid the ‘reporting’ pitfall
The most common error that businesses (and sadly even some BI vendors) make is using BI as a reporting tool.

Having BI to simply retrieve and report on records from ERP systems is like buying a Ferrari to keep in the garage. BI is much more powerful than that.

Whether it’s analysing historical, current or predicted sales, production costs or other forms of business data, BI provides up-to-date information on the state of the business – insights that allow decision makers to evaluate the effectiveness of processes and departments, to understand how the business is operating more broadly and to witness trends in sales as they occur.

To get the most from BI, make sure that your implementation is focused on strategic insights. It’s not about sales volumes or missed targets, but the reasons behind them.

5. Manage information security
BI is a potent instrument for analysing information about every aspect of a business. Unsurprisingly, however, the level of information it puts in the hands of users is a common concern for CIOs.

To this end, data security within BI solutions needs to be carefully managed, but remember that the benefits of improved information flow across the enterprise far exceed the risks.

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