Choosing middleware

Middleware is the link that helps applications inter-operate. Here’s a look at this silent performer as well as at the applications that keep a business spinning on its axis

In a perfect world, applications would talk seamlessly without colliding into barriers created by hardware and software. But as we do not live in Utopia, middleware is required if applications are to inter-operate as seamlessly as possible.

Middleware is a generic term that’s used to define software which knits applications together. It is especially important if we have to get even a little closer to concepts such as Systems Oriented Architecture.

Making the right connections

From the earliest days of software, programmers have been forced to write ‘connectors’ for different systems that may exist in a company so that these can communicate with each other.

The emergence of OLTP and other high-performance applications led to the development of commercial middleware components. These applications depended on communicating with many others to generate results. The result was that a new generation of middleware was spawned with the goal of streamlining and accelerating connections between front-end and back-end applications.

Need-driven demand

Middleware is an important part of enterprise application integration. Modern businesses require smooth exchange of information between applications such as ERP and SCM, or databases and customer-facing Websites.

Cross-application communication helps businesses benefit from consolidated information resources. Middleware makes its presence felt in various forms. A commonly-used classification is to divide middleware into the following types. Most middleware platforms use a combination of:

• Data management services (database and file system middleware)
• Communication services (remote procedure call and messaging middleware)
• Distribution services (location, time and security services)
• Object management services (by using object request brokers)
• Application co-operation services (transaction-processing monitors, e-mail, etc.)
• Presentation services (user interfaces, printing and multimedia middleware)
• System management services (configuration, change, operations, problem and performance management services).

A silent entry

Most businesses use middleware. Common components used are those in application servers, database access systems, enterprise applications and Web servers.

Commercial middleware provides software connectors that make it possible for most popular applications to interoperate. A common technique used for cross-application communication is a ‘message bus’ architecture which is also known as an Enterprise Service Bus.

An application connects to the ESB and through it to another application. The links are usually achieved using XML and Web Services or interfaces developed on Sun’s J2EE or Microsoft .NET framework. The technology is scalable and it helps avoid disorganised communication flows that can be difficult to manage as an organisation grows. It also eases application integration and management.

Middleware vendors are including enterprise technology newcomers—the likes of grid computing—in their latest products. However, these efforts are nascent and will take time to mature.

The middle path

Using proper middleware can be beneficial for Indian SMBs. The principal reason is the recent adoption of business automation by these players.

This is the right time for SMBs that are just starting on the journey to adopt proper application frameworks to employ SOA at some level. Designing a robust middleware strategy can go a long way in this direction. With such an approach, they will be able to bypass many of the mistakes that their large business counterparts made.

In an attempt to automate business using IT, many large Indian enterprises ended up with far too many interconnected applications and unmanageable dependencies. In short, it will take a while for these organisations to sort out the chaos that their application infrastructure (or lack of it) is in at present. SMBs would do well to learn from the mistakes of their large cousins and create application infrastructures using properly-designed and manageable communication channels. For this, selecting and implementing the correct middleware is essential.

Choosing middleware

So how should an SMB go about choosing middleware? The first pre-requisite is to define application requirements considering parameters such as interconnections required, applicable standards (like XML) and middleware technologies that can be used.

It is also important to keep in mind future growth plans during this sizing exercise. The middleware should be designed so that it can accommodate these changes.

Once the required features have been identified, it is time to choose a middleware solution having these capabilities. The solution should be scalable, provide access to legacy applications, support the required protocols, be remotely manageable and have scripting controls.

Development and middleware management tools are usually available with most middleware platforms. These ought to be enough for most development work, but consider third-party development tools if you find a platform lacking in the functionality you need.

Serving applications

Application servers are a form of middleware that are widely used. These act as an interface between users (internal or external) and a company’s back-end applications.

An application server is normally used in applications that are expected to deliver high performance—for example, transaction-processing. Redundancy, monitors for high availability, high-performance distributed application services and support for database access are available in most application servers. This is because most of these servers are used for high-end requirements. Hence it is common to find application servers powering e-business. These servers are used for deploying business logic processing, automating low-level core processing, middleware services, application development and providing pre-built components.

Most of the common application servers are based on the J2EE framework and act as an interface between Web browsers (users) and back-end applications. Application servers are popular as they provide an easy, efficient, cost-effective and reliable way for doing this. Load balancing is one of the features that have helped ensure the popularity of application servers with enterprises. This helps reduce the processing load in multi-tier applications.

Most applications servers are available as standalone products or as part of middleware platform solutions. Free-to-use, open source applications servers are also available.