Cloud can be thought of as today’s version of the old tech notion of service-oriented architecture. Let’s look at SOA, its benefits, and how cloud fits into the picture.

• What is Service-Oriented Architecture?
• Thinking in Terms of Services
• Benefits of Services
• How is Cloud a Further Evolution of SOA?
• How Cloud SOA is Different

What is Service-Oriented Architecture?

Service-oriented architecture (SOA) is an approach to building IT systems that embraces the service as the fundamental point of focus. Here are three basic parameters of an IT service:

1. It is logically based on a task that occurs over and over again, with a standardized outcome (such as delivering geolocation data or organizing financial documents).
2. It exists as a single entity.
3. It could also include additional services.

Thinking in Terms of Services

Service is not an idea that originally comes from IT, of course. Instead, it is a straight business term. Look in any business directory and you will immediately notice how many different types of services are being offered.

For any type of service available on the market, the company, or provider, “is offering to do something … that will benefit other people or companies (the service consumers),” notes the Open Group. “The providers offer to contract with the consumers to do these things, so that the consumers know in advance what they will get for their money.”

This notion of a service was adopted by computer scientists to describe the tasks conducted by applications. A software service is just like any other service in that it meets the needs of its consumers and is backed by a provider. There is a stated or unstated understanding between provider and consumer that the software will consistently and reliably generate accurate results.

Benefits of Services

Here are some of the advantages of utilizing services:

• Big, complex, stand-alone software is an information silo. It is shut off from external parties. In contrast, by using a system of coordinated services, there is better data exchange from one company to another. It’s also more affordable because integration of big programs becomes unnecessary.
• Building your applications based on services simplifies the process of presenting it to the world. “This leads to increased visibility that can have business value,” says the Open Group, “as, for example, when a logistics company makes the tracking of shipments visible to its customers, increasing customer satisfaction.”
• What an organization is able to do on a daily basis frequently relies on applications, and it isn’t easy to adjust huge software programs. That means it is challenging to make sure the operations of the business are adapting appropriately to meet the most recent regulations or to get the best chances for growth. Building the system based off of services allows the organization to be much more agile and much more consistently compliant with the law. The business can profit from this decision.

How is Cloud a Further Svolution of SOA?

It makes sense to set everything up as services, says David Linthicum of InfoWorld – and you can see why from the above benefits. Cloud computing is already set up as a form of service-oriented architecture, so essentially you are probably already experiencing the strengths of SOA even if you didn’t know it. Furthermore, if you’ve created apps with cloud components incorporated, you’re participating in an SOA model.

Related: It’s great that cloud has the positive features of service-oriented architecture. However, cloud technology is not all made alike. When you build your applications, you want cloud hosting that offers distributed rather than central storage (so there’s no single point of failure, among other things) and InfiniBand rather than 10 GigE, which offers tens of times lower latency. See our never-oversold cloud plans.

How Cloud SOA is Different

In what ways is the SOA of cloud different from the earlier model of a decade ago?

1. Coupling

SOA is essentially a loose coupling of systems connected via a service, notes Linthicum. In the past, “Old SOA typically exposed services from one or two systems,” he says, “and the degree of coupling could be tight or loose, depending on the application.”

The cloud-focused SOA software that is prominent now must be coupled loosely in order to function. Thousands of services are often involved in a single program. Essentially, tight coupling would make the app much more vulnerable to stopping.

2. Governance

The traditional version of SOA required governance, but a full service governance environment wasn’t necessary until you hit about 500 services. Basically more than 500 would be at about the level monitoring would start to make sense.

The cloud SOA programs require governance immediately, basically at 1 service rather than 500, argues Linthicum. “You cannot manage a set of applications that use remote and local cloud services without a sound service governance approach and technology in place,” he says. “That’s because cloud-based services are widely distributed, … so you must have much tighter checks.”