In the early days of heathcare computing, all software applicatoins ran in a mainframe environment in which dumb terminals were directly connected to mainframes for accessing data, processing patient financial transactions and other needs. But this type of environment was rather limited in terms of interfacing available to end users. Terminal applications limited users to doing one thing at a time. And these terminals lacked color, earning them the nickname "green screens," thanks to the monitors’ monochrome green glow.
Some computer experts predicted that the rise of client/server spelled the end of the mainframe. But the mainframe is not going to go away anytime soon, thanks to its robustness, scalability, ease-of-management and ability to be integrated into multi-tiered client/server systems.
Bigger is better
"There is a lot of investment in the System 390 in the healthcare industry today," says Peter McCaffrey, healthcare program manager for the IBM System 390. "The ideal scenario for most of these customers is to leverage that investment as opposed to throwing it away and starting over. Healthcare has been one of the System 390’s fastest growing industries. A lot of this has to do with consolidation."
It used to be that the cost of mainframe computers was significantly higher per unit of processing power because mainframes relied on special semiconductors that were faster, but consumed considerable power and thus required extensive cooling in order to operate. But about five years ago, IBM began using the same complementary metal oxide silicon semiconductor technology used in PCs, eliminating the need for the extensive cooling and glass houses required in the old days. McCaffrey says that this shift in technology has enabled IBM to drop the price per unit of computing power by 35 percent per year and to shrink mainframes from the size of a building to a box the size of a refrigerator.
But the real strength of the mainframe is its scalability and robustness, which will be needed to meet the transaction requirements of managed care organizations in the future. GartnerGroup, Stamford, Conn., estimates that computer transactions will explode as healthcare enters the next phase of IT systems reengineering. Analysts predict that the number of business transactions for the average 1 million-member system will rise from 124 million to 190 million transactions per year. More significantly, the number of sub-transactions, such as queries to labs, hospitals and medical record systems will grow from 414 million in 1997 to 1.5 billion in 2001.
While in theory UNIX and PC servers could be clustered together to manage this level of transactions, it would require a large number of independent boxes, which raises management concerns. "If you just look at the surface, the Intel PC environment looks cheaper, but customers are finding you need a lot more of them and the cost of managing them is prohibitive," McCaffrey notes. "There is a business value in consolidating back to a mainframe server. You can incrementally grow the processor and the speed of those processors is doubling every 18 months. In the old days, it used to be cost prohibitive to scale up because if you wanted to upgrade your environment you had to do it in large chunks. With the new technology you can incrementally grow your environment."
The client may be right
The advent of the graphical user interface enabled application developers to create more sophisticated interfaces to their programs. Healthcare software vendors such as Erisco, New York City, began developing two-tiered client/server applications in which a PC client could access data on a central server using these interfaces.
But two-tiered client/server applications ignored the mainframes that were the workhorses of the healthcare industry. This strategy limited the usefulness of client/server because of the limited scalability of servers and the extensive cost involved in migrating mainframe applications written in COBOL to UNIX or Windows NT applications written in C and C++. To address these needs, many developers began creating multi-tiered architectures that use middleware servers for accessing data wherever they reside--whether they are stored on mainframes, mini-computers, UNIX boxes or Windows NT servers.
Larry Justice, systems network administrator for Sumter Regional Hospital, Americus, Ga., points out that his organization deploys all new applications on client/server architectures because they are easier to manage and change. But they also have a number of legacy applications running on a mainframe that do not make sense to throw away just yet because of the costs and risks involved in migration.
Greg Cornellier, systems director at Harvard Pilgrim Healthcare, Hooksett, N.H., advocates building a front end using some of the newer languages used in writing client/server applications, rather than rebuilding mainframe applications. "It takes three times longer to code something in COBOL vs. something like Sybase’s PowerBuilder on the front end side," he says. Harvard Pilgrim is New England’s largest non-profit managed care organization with 20,000 physicians and 140 affiliated hospitals.