This IBM® Redbooks® Solution Guide describes the existing and new aspects of IBM CICS® Transaction Server that allow you to move your CICS applications, and business, into the mobile space. This Solution Guide gives you an overview of how to connect mobile devices to IBM CICS Transaction Server, to use existing enterprise services that are hosted on CICS, or to develop services that support new lines of business (LOB). We summarize the steps to develop, configure, and deploy a mobile application that connects either directly to CICS Transaction Server or to CICS through IBM Worklight® Server.

This IBM® Redbooks® Solution Guide describes the existing and new aspects of IBM CICS® Transaction Server that allow you to move your CICS applications, and business, into the mobile space. This Solution Guide gives you an overview of how to connect mobile devices to IBM CICS Transaction Server, to use existing enterprise services that are hosted on CICS, or to develop services that support new lines of business (LOB). We summarize the steps to develop, configure, and deploy a mobile application that connects either directly to CICS Transaction Server or to CICS through IBM Worklight® Server.

Figure 1 gives an overview of this solution.

• Reuse of existing enterprise services.
• Using the proven web service technology within CICS, it is relatively simple to build a set of enterprise services that can be used by a mobile device.
• Simplified consumption of enterprise data using Java script Object Notation (JSON) formatted data. A common misconception is that enterprise data within CICS can be hard to use. The CICS TS Feature Pack for Mobile Extensions provides support for JSON data, which is rapidly becoming the de facto standard format for data interchange on mobile devices.
• CICS operates at the heart of the enterprise. Hosting mobile applications within CICS brings them closer to the enterprise data they are accessing, minimizing application path-lengths and keeping response times down.
• Adopt a RESTful architectural style for service delivery. A RESTful architectural style is one where the target resource, and the operation to be performed against it, are defined by a combination of a structured URI and one of the four HTTP methods: Get, Post, Put, and Delete.
• Capacity to manage mobile workload. As noted earlier, customers around the world use CICS Transaction Server to host hundreds of millions, and in some cases billions, of transactions per day. CICS Workload Management provides a robust and scalable platform suitable for supporting the heaviest of mobile workloads.

• The top-down approach
  

The top-down approach, which is shown in Figure 2, is the preferred method of building new enterprise services for mobile application within CICS. This approach lends itself to the RESTful architectural style where the target resource, and the operation to be performed against it, are defined by a combination of a structured URI and one of the four HTTP methods: Get, Post, Put, and Delete. This approach allows you to create a set of services with a concise interface.


Figure 2. Top-down - a possible way to implement a JSON web service starting from the JSON schema

• Bottom-up


The bottom-up approach, which is shown in Figure 3, is perhaps the fastest approach for delivering enterprise services to mobile devices. Building on an existing SOA, the bottom-up approach allows you to define a JSON or SOAP interface to an existing COBOL, C/C++, PL/I, or Java application. This approach maximizes the reuse of existing assets, and minimizes the creation of new components.

Figure 3. Bottom up - an architecture that allows you to configure and enable a JSON web service that driven by your high-level language data structure

• Requester mode


The requester mode approach, which is shown in Figure 4, allows CICS to participate in JSON-based interactions using LINK, and to make requests against external service providers that offer a JSON-based interface. Although it is not strictly a pure mobile scenario, the capabilities that are offered by the CICS TS Feature Pack for Mobile Extensions provide CICS with additional options for connecting to the wider enterprise using JSON formatted data.


Figure 4. LINKable - a LINKable CICS program can be used to transform your data between high-level data structures and JSON

• JAX-RS
  

JAX-RS is a Java API for RESTful web services. As shown in Figure 5, it is a programming interface that provides support in creating web services according to the Representational State Transfer (REST) architectural pattern. REST is an architecture style for designing networked applications without needing complex mechanisms, such as CORBA or SOAP. The pattern involves client/server communications where the state of an application is held by the client, which reduces the processing that is required on the server. Using the IBM WebSphere® Liberty Profile provided in CICS TS V5.1, you can write your business applications by using JAX-RS.


Figure 5. JAX-RS - JAX-RS provides rapid and easy development and deployment of RESTful enabled Java applications

• As an insurance company, you want your policy holders to be able to view and makes claims on their policies directly from their mobile device. To remain competitive, the mobile application must be available as soon as possible. To facilitate rapid development and provide your services that are hosted on CICS to the application, you choose to take the “bottom-up” approach. Using your COBOL copy books, you generate the JSON schema that allows the mobile application to communicate with CICS web services with a lightweight payload. CICS manages the transformation between the JSON and COBOL copy book structure and your CICS services are made available.
• As a CICS Service provider, you have a business requirement to make your CICS applications available through a standardized RESTful pattern. By using the “top-down” approach, you can externalize your existing and new CICS services through a RESTful architecture, which allows your services to be called through a unified approach that is understood throughout the business
• As an airline carrier, you need data from your business partners to accurately allocate seating through your on demand ticket purchasing system. You are informed that your business partner externalizes their services only through a RESTful pattern with JSON as the data format of choice. You can use the new CICS provided LINKable program along with the existing CICS web API to communicate with the business partner without the added cost of development and maintaining a bespoke communication layer.

• IBM Worklight is a hybrid mobile solution offering governance and a powerful SDK to build applications with a server component that drives the mobile world.
• IBM DataPower® allows you to secure, integrate, and optimize SOA capabilities that scale.

• IBM WebSphere MQ
• IBM DB2®
• IBM Integration Bus (formerly, IBM WebSphere Message Broker)

• IBM CICS Transaction Server, SG24-8161
  http://www.redbooks.ibm.com/abstracts/sg248161.html
• IBM CICS Transaction Server product page
  http://ibm.com/software/products/us/en/cics-tservers
• IBM Offering Information page (announcement letters and sales manuals):

http://www.ibm.com/common/ssi/index.wss?request_locale=en

On this page, enter products/us/en/cics-tservers, select the information type, and then click Search. On the next page, narrow your search results by geography and language.