Application Architecture Overview for CICS Transaction Server

IBM CICS Transaction Server is a transaction processing server that operates primarily on IBM System Z mainframes based on IBM z/OS. It controls the interaction between an application and a user (from a small number of users to thousands). CICS applications provide high reliability and scalability. The CICS application is flexible and can use a variety of customer interfaces: from the terminal, from the Web browser to the Web service.

As explained in the IBM Redbook Solution Guide, the CICS Application architecture has some business and technical advantages.

For information on topics, see the following IBM Red Book:
Architect ' s Guide to IBM CICS on System z, sg24-8067-00

Content

IBM CICS Transaction Server is a transaction processing server that operates primarily on IBM System Z mainframes based on IBM z/OS. It controls the interaction between an application and a user (from a small number of users to thousands). CICS applications provide high reliability and scalability. The CICS application is flexible and can use a variety of customer interfaces: from the terminal, from the Web browser to the Web service.

The CICS trading Server has a wide range of capabilities to serve the applications deployed on it. The CICS architect can rely on the Run-time services provided by CICS without having to design these services into application code. These services include security, transactional integrity, and scheduling of multiple processes or hardware clusters.

As explained in the IBM Redbook Solution Guide, the CICS Application architecture has some business and technical advantages.

Figure 1. CICS Application Architecture

Do you know?

CICS was first released in 1969 and is still popular today. A large number of commercial electronic transactions are handled by the CICS Transaction Server.

More than 30 billion of transactions per day are handled by CICS.

At least three CICS customers achieve a one-day transaction volume of 1 billion.

CICS deals with 1 trillion of dollars a week.

Business value

The CICS Transaction Server is an administrative environment for handling high-volume, efficient, transactional applications. There is no need for developers to write system functionality in their applications, and CICS can perform these services automatically or according to application requirements.

By using CICS, developers can focus on writing business logic code to solve business problems without having to worry about system functionality, such as database integration and security control.

This can bring customers the following advantages, including a shorter development cycle, easier to maintain, and easier to add new features. Applications do not need to be accompanied by a new operating system or database, because the CICS Transaction Server processes interfaces with these systems.

CICS provides a fast, low-cost, and Low-risk way to develop business applications. The support of CICS's multiple programming languages provides an important convenience for cost saving and productivity improvement.

Solution Overview

CICS provides a set of APIs to simplify access to CICS-managed resources. This set of APIs supports CICS container services, ensuring real-time quality of service including transactional, security, and load management.

The CICS API provides a neutral, standard language interface to access files, queues, programs, and other resources, significantly enhancing the efficiency of application development. At the same time, CICS separates the business logic from the system management logic through the API, and realizes the modern development model. Users do not need to use the language of their own syntax, can be completed for file reading and writing. Users can also run the CICS command by indexing resource aliases and specific APIs.

Another benefit of the CICS API is that it implements the compatibility of loading modules across the CICS version. Even if a particular API is no longer supported or removed, the module can still be used in a new version of CICS if the module using the API can handle related errors.

The choice of commercial application development languages is often based on the needs of the users and their existing skills reserves. Because CICS supports multiple languages, applications in CICS are run in a truly heterogeneous environment, with application development languages including process languages (such as COBOL) and object-oriented languages such as Java and C + +.

Figure 2 summarizes the programming languages supported by CICS.

Figure 2. CICS Programming Environment

The core of the CICS language support is IBM z/OS Language environment. CICS integrates the runtime of different languages through LE. Various programming languages (such as PL/1, COBOL, and C + +) have their own libraries in Le, so CICS can provide simple communication of different programs at the language level. Rexx has no links to the Le library because of its direct use of CICS services.

The CICS Multi-language runtime has the following advantages:

Communication between languages provides better flexibility and efficiency for design and development. It also allows developers to choose the most appropriate programming language for different projects for different purposes.

The CICS API provides a standard interface for interacting with CICS-managed resources. CICS also provides a Java API. Java APIs are implemented in Java, but run in exactly the same standard API as CICS. Java's API simplifies the development process, compatible with other languages, and makes it easier to take advantage of the quality of service at the CICS runtime, such as security, load management, and transactional.

Centralized diagnostics, where the system outputs the information in a standard way when the problem occurs. This reduces the time and effort to diagnose resources and improves the quality of applications.