For z/OS platforms

Optimized local adapters usage scenarios for Liberty for z/OS

Real-world scenarios illustrate how optimized local adapters and the supporting native API callable services provide can benefit enterprise architecture and application development on the z/OS® platform.

WebSphere® optimized local adapters (WOLA) provide existing native-language business and middleware applications in z/OS batch, Customer Information Control System (CICS®), and UNIX System Services environments an alternative way to call Java™ applications that are implemented as Enterprise JavaBeans (EJB) applications on Liberty. Using optimized local adapters, you can also call from Liberty applications to an external server program that is running locally or on the same logical partition (LPAR) using Java EE Connect Architecture (JCA) Version 1.5.

A scenario where the optimized local adapters can provide increased performance is CICS support for the use of server and client web services. The targeted backend applications can call business logic that is located elsewhere more efficiently when using the optimized local adapters instead of XML and SOAP messaging technology.

The following hypothetical real-world scenarios describe how optimized local adapters are useful to achieve various business goals.

Financial services company scenario

An IBM® z/OS financial services customer that is running business applications under z/OS batch must decide about purchasing a financial processing application, which provides new support for stock trade real-time reporting to the exchanges. The ability to do this style of real-time reporting can result in increasing revenue for the customer.

The application that does real-time reporting is a Java Enterprise Edition (Java EE) application on a Liberty server that runs on Windows 8. The application offers a set of enterprise beans and associated web services interfaces that can be called for various kinds of interactions.

A test scenario is developed and successfully implemented to call the Java EE application from a batch Cobol program. Therefore, the customer decides to move forward and do more rigorous testing. Further testing shows that when this mechanism is pressed by more than 50-100 requests per second, it begins to slow to the point where the response times do not meet the customer requirements. The effort is abandoned until a more realistic approach is available for exchanging information in real time between the batch business application and the new vendor application.

The optimized local adapters can provide this batch customer with an option to deploy Liberty for z/OS and update the batch application to use the optimized local adapters Invoke or Send Request API. These APIs provide a way to call EJB applications that are deployed on a local Liberty server, which calls the business logic for the web service.

Insurance company scenario

An IBM z/OS insurance industry customer that is running a business application under CICS wants to provide customers with the ability to retrieve and update policy information in real time. This information must be gathered in various ways and from several places, including:
  • Information that is directly gathered from DB2®
  • Information that is gathered by calling a program in CICS
  • Information that is gathered by starting a web service to communicate with a remote service provided by another company

The customer chooses to use a Java application for several reasons, but most importantly because most of their programming skills are based in Java. When the new application is tested, the customer experiences long response times when retrieving information. The slow response time is a result of the Liberty server running on a distributed server and the latency that is involved with communicating remotely with DB2 while it calls CICS using web services and SOAP messages.

To fix the problem, the customer deploys multiple Liberty servers in the same configuration to reduce the number of requests per second on any one of the servers and to spread the requests across separate network paths.

Using optimized local adapters gives the customer an alternative other than deploying multiple servers. The customer could install the application on a Liberty server on z/OS, closer to the DB2 and CICS environments. Using the optimized local adapters APIs for the calls to CICS from the Liberty server provides a significant improvement over the web services and SOAP solution. Consolidating on z/OS platforms reduces the need for more distributed servers that consume floor space, power, and resources to maintain. In this scenario, because the location of the data and applications is the gating factor, increasing the size of the remote server to the most robust one available does not necessarily solve the problem.

Migrating business logic to Liberty for z/OS

A customer has years of application logic with Cobol running inside of CICS. They want to migrate some of these applications to Liberty to take advantage of Java and Java EE technologies and use other capabilities in the WebSphere stack.

One of the applications is too large to migrate in one piece, and they want to gradually move portions of it to a Liberty server. The transactional and security qualities of service that CICS provides must be maintained during the migration, and any adverse effect of the migration on performance must be minimal. Using optimized local adapters, portions of the application can be migrated to Liberty and wrapped in a stateless session bean. The Cobol application logic can be modified to use the optimized local adapter to call the stateless session beans. These calls to the Liberty server run under the same transaction and security contexts that are used by the Cobol programs in the CICS region. There is a significant performance gain when compared to making similar calls using a web service. The customer can continue to relocate portions of the application to the Liberty server until the application is migrated.


Icon that indicates the type of topic Concept topic

File name: cwlp_dat_usagescenarios.html