IBM CICS Transaction Gateway has been proven over many years to provide high-performing, security-rich and scalable access to CICS Transaction Server, requiring minimal changes to CICS systems and usually no changes to existing CICS applications.
With IBM CICS Transaction Gateway for z/OS, Version 7.0, you can use your CICS communications area (COMMAREA)-based applications in comprehensive and sophisticated Java™ and Web services solutions hosted on IBM WebSphere® SOA Foundation server products such as IBM WebSphere Application Server, IBM WebSphere Enterprise Service Bus (WebSphere ESB) and IBM WebSphere Process Server.
High-performing, security-rich and scalable connectivity
Running CICS Transaction Gateway on the IBM z/OS® operating system provides the highest quality of service of all the environments in which CICS Transaction Gateway is supported. In the z/OS environment, CICS Transaction Gateway can support thousands of transactions per second by using multiple gateway regions, and by reusing memory-based External CICS Interface (EXCI) pipes. CICS Transaction Gateway uses a multithreaded daemon to handle communication with front-end application servers and back-end CICS systems. Deployment code is optimized, enabling support for large numbers of concurrent requests and sub-second response times to users.
Remote communication is Internet Protocol (IP)-based, and CICS Transaction Gateway provides comprehensive Internet Protocol (IP)-based security features, including support for Java Secure Socket Extension (JSSE) Secure Sockets Layer (SSL) and now Transport Layer (TLS) encryption between the WebSphere SOA Foundation server and CICS Transaction Gateway. An external configuration option that allows you to specify the SSL cipher suite enables you to define the level of security at the application level, and provides the capability to take advantage of new levels of encryption as they emerge. You can even map SSL certificate identities to IBM RACF® user IDs, providing integration with existing CICS security mechanisms.
Rapidly and easily add SOA capabilities to existing CICS applications
CICS Transaction Gateway for z/OS is designed to enable rapid and easy deployment, using the System Modification Program Extended (SMP/E) standard tool for installation and maintenance. A user-friendly configuration infrastructure expedites the initial setup of CICS Transaction Gateway, and enables multiple Gateway daemons on the z/OS platform to be configured and run independently to maximize scalability and availability. A set of extended z/OS system commands provides a simple and secure way to manage, control and monitor your CICS Transaction Gateway for z/OS environment.
An External Call Interface (ECI) JCA resource adapter enables COMMAREA-based CICS applications to interoperate effectively with WebSphere applications. Using Java servlet or Enterprise JavaBeans (EJB) components, CICS Transaction Gateway allows high-performing access to existing CICS COMMAREA-based transactions, while requiring minimal changes to CICS and usually no changes to existing CICS applications.
Maximum transactional integrity
One advantage of deploying CICS Transaction Gateway on the z/OS platform is the provision of XA two-phase-commit transactional integration between physically distributed WebSphere SOA Foundation servers and CICS Transaction Server applications running on the z/OS platform. This capability enables CICS Transaction Gateway to fully participate in a global transaction, where units of work can be coordinated across different resource managers (such as IBM DB2®, IBM IMS™ and SAP software). Two-phase-commit helps ensure that the entire transaction can commit successfully, or if some error condition occurs, be entirely returned to the state before the transaction. With global two-phase commit, you can physically distribute a composite transaction across heterogeneous servers and operating environments, helping to maximize flexibility without compromising data integrity.
Two-phase-commit transactions work by requiring a PREPARE command to be confirmed by each resource manager, before a COMMIT command makes all transaction changes permanent. This capability is provided through the provision of an XA-capable JCA resource adapter and the use of the z/OS Resource Recovery Services (RRS) subsystem. After a resource manager makes a positive response to a prepare request, the resource manager enters a contract to commit the work as part of the global transaction. This decision is persisted in RRS, so that even if the connection is lost or CICS Transaction Gateway is restarted, the controlling transaction manager can recover and commit the work, helping to provide the highest levels of integrity for the entire global transaction.
CICS Transaction Gateway for z/OS, Version 7.0 also supports local-mode global transactions. This capability provides optimized two-phase-commit support when the WebSphere SOA Foundation server and CICS Transaction Server for z/OS are located on the same z/OS logical partition (LPAR). This configuration also provides the highest qualities of service because communication between the CICS and WebSphere server is provided through shared memory rather than over a network connection.
For more information, please refer to the CICS Transaction Gateway for z/OS, Version 7.0 Announcement Letter, and the CICS Transaction Gateway On-line Library.
