HostBridge Technology


CICS Web Services Using JavaScript

Integration, Orchestration, Optimization for CICS Applications

IBM® CICS® Transaction Server remains one of the most powerful and reliable transaction server systems in the world. For thousands of enterprise customers, CICS handles more than 30 billion transactions valued at over $140 billion per day. At one time, CICS was accessible only to trained operators inside the enterprise. Today however, thanks in large part to Web services, CICS applications are at the fingertips of 30 million employees, partners, and customers everywhere.

A Web services layer between CICS and the outside world allows CICS to interact with virtually any other information system –other business applications inside the company, systems running at partner organizations, cloud resources, or Web servers connecting to client devices of every kind. By deploying CICS Web services, user-organizations are able to make CICS a full participant in the world of modern interoperability while avoiding the expense and effort of re-engineering and migration.

CICS Web Services and HostBridge JavaScript

When it comes to Web services for CICS, HostBridge, with its JavaScript Engine (HB.js)[1], offers a number of advantages over other solutions. Like other solutions, HostBridge supports SOAP and RESTful standards and protocols, but the JavaScript approach that is unique to HostBridge services ensures easier development, faster deployment, higher fidelity to CICS applications, more reliable integration, and unique capabilities for orchestrating, automating, and optimizing terminal-oriented applications.

Orchestrating and Automating CICS Transaction Micro Flows
Carrying out a complete business process with a terminal-oriented CICS application – e.g., getting an insurance policy overview – can require navigating through a complex micro flow involving dozens or even hundreds of screens. Whether the request is made by a human being or a distributed system, it historically required traversing one screen at a time and gathering data from screen after screen. Each interaction required a full request-response cycle and a full transit of the network, increasing process latency, impacting system performance, and reducing productivity.

HB.js handles these transaction micro flows far more efficiently, effectively, and reliably. When a requesting system or user interacts with CICS via HostBridge, they invoke a single HostBridge Web service – Get Policy Overview – that orchestrates the micro flow, automates the aggregation of data from all necessary screens, and returns a single response. The result is the highest possible system performance and a highly stable, reliable integration.

Dynamic Applications
Increasingly, customers use the HostBridge JavaScript Engine to create dynamic new applications at the Web services layer without modifying mainframe code in any way. In effect, they are transforming legacy applications into modern, object-oriented, interoperable applications. One customer has used HostBridge to encapsulate thousands of CICS screens in thousands of unique, discrete JavaScript modules. Each module includes all the data and functionality of its corresponding screen. At a higher assembly level, the customer has written JavaScript Web services that “require” any number of modules needed to complete a single business service.

Without changing the backend application in any way, the customer has rendered it thoroughly modern, dynamic, and adaptable to meet any business need. Each business service the customer creates can be readily incorporated into modern front-end applications to radically improve human usability or integrated with other business applications and services to improve business process efficiency throughout the organization.

Reusable Web Services
Reusable Web services or JavaScript-based objects of the kind described above can be used tactically to address immediate integration needs. At the same time, they function as ready-made “building blocks” for more complex integrations or for integrating CICS applications into enterprise service-oriented architectures.

Web Services Types: SOAP and REST

While there are numerous issues to consider when contemplating CICS Web services, some basic concepts help guide initial decisions. First are the types of services themselves. Web services come in two basic “flavors” – formal SOAP services and less formal RESTful services.

SOAP is more formal than REST in the sense that SOAP standards are more rigorously defined and fully developed for situations in which security, governance, and business policy are critical. SOAP services require more human planning and effort, as well as machine processing, on both sides of the connection. Deploying SOAP services is generally appropriate when:

RESTful services are less formal in the sense that their standards are less rigorously defined and security and governance are somewhat less critical. RESTful services are generally appropriate when:

The following table outlines some of the factors involved in choosing between SOAP and RESTful services:

Style Pros Cons


  • Language, platform, and transport agnostic
  • Designed to handle distributed computing environments
  • Prevailing standard for Web services/service-oriented architecture
  • Better support from other standards (WSDL, WS-*) and tooling from vendors

  • Conceptually more difficult, more “heavy-weight” than RESTful services
  • Harder to develop, slower to deploy
  • Requires tools
  • Language and platform agnostic
  • Simpler to develop, faster to deploy than SOAP services
  • Short learning curve
  • Less reliance on tools
  • Concise, no need for additional messaging layer
  • Assumes a point-to-point communication model
  • Not usable for distributed computing environments where messages may go through intermediaries
  • Lack of standards support for security, policy, reliable messaging, etc., so services with more sophisticated requirements are harder to develop
  • Tied to the HTTP transport model

Whether your organization plans to implement or has implemented SOAP or RESTful services for CICS integration, HostBridge can meet your need. To review the full range of Web services technologies, protocols, and transports supported by HostBridge, download our latest version data sheet with technical specifications.


[1] HB.js was formerly known as the HostBridge Process Automation Engine.