1. INTRODUCTION

About This Document

This document describes the procedures followed in transforming a legacy application to an open application system under Horeb.

Aim

• Retiring the mainframe hardware, but retaining the their characteristics, such as, reliability, security, scalability, performance and availability.
• Replace the existing legacy system by an Open System; that neither has restriction for hardware and software products nor any topological constraints.
• Provide services for online customers with due security, and lessen the paper work and conventional office management procedures.

Audience

Horeb Transaction Processor is useful for any business, or person who manages their own accounts. HorebTP is a business processing system. Most large businesses currently use IBM mainframes for their business processing. However, mainframes are very expensive to maintain and use. Horeb provides businesses of today more capabilities in business processing at a higher performance, less expensive, maintainable manner. Since mainframes are so expensive to use and maintain, many businesses cannot afford them and at the same time are restricted in their growth. Horeb is affordable and allows them to grow. Even home users can use Horeb for mananging finances through our soon to come subscription service for business processing for home users and small businesses.

2. LEGACY APPLICATIONS

The term Legacy Application denotes the application running in IBM mainframe using MVS or DOS/VSE and transaction processors like CICS, IMS, ADABAS, IDMS etc.,

These applications are the nucleus of business processing.

In spite of the phenomenal success of web and java, the mainline business processing corporate sectors are unable to adapt these technologies. The following are the reasons:

• Web is never an alternative to a programming language. Web is only a document script.

• Java virtual machine (JVM) is not capable of providing a same processing speed of a transaction processor, running under OS/390

• Java is no Cobol. The expertise required for Java programming makes it expensive and difficult produce code at a rapid pace, for which Cobol is renowned.

• Due to large volume of data exchange, which is demanded by Web/Java the transaction rate is far below the expectation of the business-processing standard.

• Business processing is larger than look and feel type of presentation features. It has online data processing, batch network, storage management, operations, system and application maintenance, quality assurance, change control, disaster recovery and much more. These nuclei concepts are alien to people involved in web and java.

The list goes on. However, the main theme remains the same: under the current conditions, the corporate America will not change their legacy application or platform, risking their entire lifeline. Therefore the mainframe solution providers keep their price high, knowing well that the clients have nowhere else to go.

On the other hand, mainframe provides important features, which cannot be guarantied under the web application platform. They are as follows:

• Reliability: the application is up and running all the time.
• Performance: the response rate for any business transaction is quick enough to support the administrative staff or general client
• Security: all data are secure and exclusive to only the person who owns them or who process them. Breach of security is extremely rare. Viruses or worms never attack mainframe applications.
• Scalability: all solution offered are upgradeable without causing any system outage.

3. NEED FOR A CHANGE 

In spite of the features, the corporate sector is embraced to change the legacy application into a more accessible open system.

A open system is an application system that is available in the internet and accessible from all over the world and can run in any hardware, hence unlocks the vendor dependence and expensive product leases.

The following are the reasons why CEOs and CFOs would like to see the legacy applications go.

• Long ago hardware prices have fallen; yet, the annual budget for data processing is still high and souring.

• Accessing legacy application outside the company network is extremely cumbersome and creates security problems. Hence web enabling is not always possible.

• Current technology is not immediately available.

• Extremely user unfriendly, 3270 emulation screens, which are commonly used to collect data. Even if this is changed using web-enabling, it is still active behind the scene.

• Collected data are held in isolation and not in a convenient location to share with other applications and platforms.

4. HOREB TRANSFORMS

HOTP was envisioned to replace the legacy applications. Most of these legacy applications are in IBM mainframe and they run under a transaction processing system like CICS, IMS, IDMS, ADABAS and the like. This is the main reason why HOTP as a system-software developed as a transaction processor. More information on HOTP can be found in HOTP Principles of Operations.

Before looking at how HOTP can transform the legacy application to a open application system, it is necessary to know what comprises legacy system.

The following features and components bind a legacy application system.

• Hardware platform: this involves IBM mainframe involving, CPU complex, disk drives, memory complex, channels, tape drives and controllers.

• Software platform: operating system (like z/390, OS/390, DOS/VSE/VM), transaction processor (CICS, IMS, IDMS etc.,), storage management software (CA1, SMS), security system product (RACF), network software (VTAM, NCP, TCP/IP), operations management system (CA7), language environment (cobol, c, assembler etc.,), diagnostics software (Expeditor, Abend-Aid), database software (DB2, oracle) and so on. On the average there are some 100 system software that need licensing each year.

• Application systems: Thousands of programs, which are home grown and cannot, be easily discarded or redeveloped. These are main reason why the above hardware and the software should stay. An average size of legacy application code per company is 7.5 million lines of code. 

HOTP transforms legacy systems using the following means.

• All user inputs and outputs are defined to HOTP as and they are called HOTP transactions.
• All application programs, each one of them are feed to a translator which converts all the operating system interfaces to HOTP interfaces, enabling these application to reside in any server platform
• All database files are converted into the preferred database system or HOTP internal database system
• All other functions are provided by HOTP components called managers as explained in HOTP Principles of Operations.
• With this transformation, mainframe is gone, its software packages are gone. Being an open system all programs are run in distributed internet servers and are accessible through HOTP transaction throughout the IP world, with correct security.

5. TRANFORMATION STEPS

The transformation takes place in the following steps. The whole procedure takes place between four to six months.

• All legacy application program features are studied through program analyzers and user interviews.

• A distributed server platform is constructed in accordance with client preferences. This formulates the System Analysis Report.

• All application program code and interfaces are used to formulate the Application Analysis Report.

• Network is defined in accordance with System analysis report

• HOTP transactions are defined in accordance with Application analysis report

• Databases are defined and data conversion takes place as specified in the Application Analysis report.

• Application programs are translated to accept HOTP transactions.

• Translated application programs are distributed among the servers

• Clients are defined to security database

• Program and system administration are defined to admin database

• Other system databases are populated depending as per System analysis report, which replaces all administrative functions.

• System testing and completion of implementation

• User training and skill transfer

• Post implementation plan created, which defines the support and version upgrades.