Up to three-quarters of an enterprise data is managed or stored on a mainframe. Research by IBM user group SHARE has revealed that the mainframe, which conventional wisdom had was old technology, is playing a big part in modern enterprise systems.

According to SHARE, 30 percent of respondents who work for companies with 10,000 or more employees said between 51 percent and 75 percent of their company's data is held on a mainframe.

The workhorse's renaissance is being driven by the growing use of SOA. The study said that mainframes are integral to SOA by default since they contain a large portion of the world's business information. According to the research, nearly 23 percent of respondents said their company was undergoing a SOA project, and another third said SOA was in the planning stage. Thirty-seven percent of respondents said they were pursuing an enterprise-wide SOA, but in most cases the projects are confined to niche instances, such specific lines of business or divisions or within applications.

"Many of the applications that need to be SOA-enabled are mainframe applications," said Pamela Taylor, vice president of strategic development for SHARE and a solutions architect for a subsidiary of a Fortune 50 company. "System z tends to be absolutely critical to deployments."

While mainframes play a dominant role in hosting an enterprise's data, companies' interaction with that data faces constraints. At least 50 percent of the companies surveyed use hand-coded scripts to push mainframe-based data to other databases or platforms, according to the study. Such scripting is hard to maintain, particularly if the programmers who wrote it leave the organisation, the study notes.

The study did note that SOA could strain systems, such as through its use of XML-based messaging. "Rather than acquire more server hardware to attempt to address growing SOA performance issues, mainframes may represent a more cost-effective option for leveraging existing resources," the study states.

In turn, the abstraction layer a SOA provides can help enterprises more easily tap their existing mainframe applications and data, the study notes.

Sales for System z fell last year but IBM is banking on the launch of its next-generation mainframe in February.