February 01, 2001, 11:20 AM — A new software product will dramatically simplify the work of bringing mainframe transaction data into Web-based applications.
HostBridge, from HostBridge Technology Inc., acts as an XML interface for existing transactions in IBM's widely used CICS transaction processing software. The interface converts CICS data on the mainframe into an XML document, which is then sent to midtier application servers for processing or display (see graphic). No coding changes are needed on the mainframe.
HostBridge completely sidesteps the use of 3270 datastreams, which are traditionally used to display CICS data on a terminal screen. So-called Web-to-host software today is a set of programs, plus additional coding work, for what's called screen scraping: The software creates a kind of coordinate mapping system to find the data on the screen, then extracts and packages it for use in a new application.
Screen scraping has several shortcomings, says Marshall Gordon, systems architect with Caspian Consulting, a San Francisco IT services company that's about to launch the first customer trial of HostBridge. Web-to-host software doesn't easily handle large transaction volumes, and soaks up CPU cycles on the host and the midtier servers, he says. It's also fragile, and requires a high degree of ongoing maintenance -- any changes to the host application will mess up screen scraping software unless that is changed as well.
These were the problems that Caspian encountered as the distributed systems arm for its main client, Delta Dental of California, a large dental insurance organization. Gordon took his problems to Russ Teubner, a programmer and entrepreneur who's written several host integration products, including Corridor, all of which were acquired by Esker Software. Caspian was using Corridor to pull CICS data into Web applications. The system, based on Windows NT servers, is currently supporting about 6,000 requests per hour, each one typically needing 15 to 20 CICS transactions.
For HostBridge, Teubner used a little-known CICS API introduced by IBM about a year ago, called 3270 Bridge. The API lets any other program work directly with "raw" CICS data before the data is formatted into a 3270 datastream.
The HostBridge software, which runs on the mainframe, uses the API to grab data and convert it into XML. "I chose XML because it can be processed by virtually any midtier application or application server," Teubner says. "And it also lets any application that can generate XML now communicate with the host application."
"It's unique," says Dale Vecchio, an analyst with Gartner Group Inc., a technology research company. "It intercepts 3270 data, transforming it into XML, which makes a lot of sense to companies that want to [mine] legacy applications for data to populate new [midtier] applications."