Tools of the architect's trade

Air France is using event-driven architecture to improve passenger check-in and boarding procedures. Pic credit: Oneras

Few organisations have the luxury of being able to design a purpose-built enterprise IT architecture from scratch.

In most cases, enterprise architects are presented with a mass of disparate systems, applications and data sets inherited from various parts of their own and other companies’ businesses – often merged through acquisition – and are asked to use the parts to create a more efficient platform for IT service provision.

That is a difficult task in any case, but there are established platforms, applications, frameworks and governance tools that can be used to underpin that construction, with technologies that support service-oriented architecture (SOA), business process management (BPM) and application integration all playing a big part.

SOA has gained momentum in the past few years, having been widely implemented by many organisations as a way of converging software platforms using interoperable, re-usable components and services across IT.

Companies such as IBM, Oracle, SAP, HP, Microsoft and Tibco sell SOA middleware platforms that are usually centred around a standards-based enterprise service bus (ESB). Open-source equivalents are also available from the likes of Sun Microsystems, for example, which is soon to be acquired by Oracle.

“Vendors that say they provide SOA platforms mean they provide some sort of application container that an organisation can use to develop random services – typically an application server of some sort – then a set of tools to help build the consumer side of the application, such as a portal infrastructure, and some specific web-oriented development tools,” says Massimo Pezzini, Gartner research vice president.

“Finally, there is an intermediate, middleware layer that glues all these things together from an interoperability and connectivity perspective, which is the ESB.”

The ESB is the software that enables business applications to communicate with each other via a software broker, using frameworks such as J2EE or .Net, for example. SOA platforms also incorporate business process execution language to handle the way that applications interact with web services to support related business transactions.

“Most ESBs are based on J2EE and .Net, but others are more web services-oriented and some are more relevant to multi-lingual SOA environments,” says Pezzini. “There are also lightweight alternatives to J2EE which provide less complex types of development.”

Web services are an important element of any efficient enterprise architecture because, alongside common application programming interfaces (APIs), they are widely used as portals to underlying, back-end, legacy applications that form the bedrock of everyday operations.

Will Barnett is former head of IT enterprise architecture at Thomson Reuters. He spent 15 years in the IT, finance and retail industries, including a stint as information architect at Tesco, where he built a real-time global enterprise architecture infrastructure, extract-transform-load data warehousing system and web
services platform.

“It is all about using web services and common APIs to build a single fabric, so it looks as if you have a single back end even where you don’t because you have pockets of different operating systems, for example, or other legacy systems,” he says.

“You need common interfaces for passing content between business units, and building web services based on JMS, IBM’s MQ, Microsoft Message Queuing and shared FTP means you do not have to rip and replace between existing systems, for example.”

In an ideal world, the user would not know whether the service is based on Cobol, Java or any other programming language, says Pezzini.

“Legacy mainframe applications, whether SAP or Siebel for example, are integrated into the SOA framework via the ESB, which makes it possible to expose non-SOA applications through new adapters or interfaces,” says Pezzini, who estimates that about 70 per cent of SOA-enabled applications are actually legacy applications wrapped in SOA interfaces.

Event-driven architecture

In many cases, SOA platforms include more sophisticated tools such as workflow and event processing applets, as well as BPM applications. All these help support the concept of the event-driven architecture (EDA) – how different applications, components and services interact with each other to provide automated transaction processing between systems, following pre-defined business and complex event-processing rules.

Gregor Baues is chief architect at Air France, the airline that is in the process of merging with Dutch rival KLM. Since 2004, he has been responsible for various application infrastructure initiatives such as a mobile J2EE application architecture, an enterprise web portal, content management and the introduction of RFID to the Air France enterprise information system.

Baues’ business challenge was to create a seamless customer “smart boarding” interaction that allowed Air France passengers to check in and self-board using RFID and biometric technology. The company is now looking to extend that operation into baggage handling so that passengers can check the whereabouts of their luggage using their mobile phones.

“It is totally event-driven and generates a huge amount of paper. Time is critical and all new business demands call for more complex data interaction with our partner systems,” says Baues.

“So long as we provide the drivers/plugs for all these devices, we can capture the information and send it out to other environments such as baggage-handling services.”

For Air France, those events can be both IT and non-IT related, and can come from internal and external sources, such as messages or weather forecasts.

“But they all have to be managed within an event-driven architecture, and fi nding the application is a big part of that. We use SOA connectors based on a message-oriented asynchronous mechanism, and the EDA model for a specific type of service,” says Baues.

Other parts of enterprise architecture (EA) rely on management tools to help manage the EA environment, as well as a repository containing information about the services that are running.

“These tell you what services are available, what they look like and what an application needs to do to connect to them using what protocol when they are running,” says Pezzini.