Transform your mainframe system to the right platform for the future
Mainframe rehosting is the process of legacy system migration and implementation, to free your legacy system while maintaining the integrity of your existing business logic and data.
What is mainframe rehosting?
Mainframe rehosting essentially consists of taking a legacy system that resides within a mainframe machine and moving it wholesale to another platform, typically a more flexible and cost-effective 'open system.' This, of course, is not a simple process. To ensure that the legacy system is migrated safely, rehosting should only be carried out by experienced personnel following a verified procedure and using the best software tools available.
A simplified summary of the steps involved in rehosting a mainframe-based legacy system is as follows :
Why rehost your mainframe-based legacy system?
Most large-scale IT legacy systems in use today reside within mainframe machines, as they have for the past several decades. However, more flexible and cost-effective alternatives to the mainframe have emerged, and thus more and more companies are moving away from the mainframe. Mainframe rehosting (otherwise known as mainframe migration) is one option for moving away from the mainframe and pursuing legacy modernization.
- What are some of the benefits of selecting mainframe rehosting as your avenue for legacy modernization?
- 1. Rehosting is low risk, especially in comparison with other modernization options.
- 2. Rehosting is low-cost, primarily because:
- 3. Rehosting reuses the original business logic and other assets from the original system.
- 4. Rehosting can increase flexibility, standardize the system environment, increase transparency, and reduce the system's overall total cost of ownership.
- 2. Rehosting is low-cost, primarily because:
Despite being perhaps the safest legacy modernization option, rehosting should not be undertaken lightly. Legacy systems typically house applications and data that are central to a company's competitiveness and thus rehosting should only be performed by experienced professionals using the most sophisticated software tools available.
TmaxSoft has a great deal of experience in using OpenFrame to rehost large-scale enterprise systems. OpenFrame provides an appropriate open system environment for rehosting mainframe-based legacy systems and was developed entirely in-house at TmaxSoft. Importantly, OpenFrame incorporates a range of tools and utilities that largely automate the actual migration process.
TmaxSoft system engineers have used OpenFrame to successfully complete rehosting projects across a variety of industries throughout the world, including some of the largest rehosting projects ever undertaken.
Beyond Rehosting
A particularly common strategy for companies with large-scale mainframe legacy systems is to rehost to an open system platform and then start re-architecting the legacy applications one by one. TmaxSoft excels at implementing this strategy as OpenFrame (the base product for rehosting) and ProFrame (the base product for re-architecting) are 100% intercomparable. This means that rehosted legacy applications running on OpenFrame and re-architected applications running on ProFrame can operate side-by-side without any compatibility issues.
OpenFrame is the most sophisticated rehosting solution available. Some of the highlights of OpenFrame include:
OpenFrame provides a range of modules that enable the various mainframe legacy resources (including applications) to operate within the open system without modification. This ensures that the original functionality and business logic is maintained.
OpenFrame incorporates a range of tools and utilities that largely automate the analysis, migration, and verification steps in the migration process. This ensures that the migration process remains stable and is free of human error.
Batch tasks have a reputation of being impossible to migrate efficiently and other rehosting solutions require that JCL be rewritten as inefficient shell scripts. However, OpenFrame provides sophisticated JCL processing engines that enable mainframe JCL to run within the open system without modification of the original logic. Additionally, TmaxSoft's system engineers have a great deal of experience in optimizing JCL for operation within open systems.
Moving to an open system with OpenFrame provides access to vendor-independent hardware, which is typically much cheaper than similar vendor-specific hardware. Additionally, the maintenance and licensing fees for open system hardware and software are much cheaper than those of mainframe products.
Open systems can offer higher levels of agility, expandability, and flexibility than vendor-specific environments. Within open systems it is much easier to implement new applications, modify existing applications, and to integrate new technologies. Thus open systems are more flexible and capable of quickly and seamlessly incorporating new functionalities or technologies.
OpenFrame provides an advanced middleware platform that facilitates efficient distributed processing, load balancing, fault tolerance, and other features. This ensures that all OpenFrame-based systems provide levels of performance and reliability that meet or exceed the mainframe.
While the standard OpenFrame software can be used to rehost mainframe CICS, IMS and Batch systems, OpenFrame AIM has been developed to facilitate the migration of Fujitsu AIM resources. With OpenFrame AIM, legacy system resources residing within a Fujitsu AIM operating environment (which uses ADL (AIM Description Language) and AIM commands) can also be migrated to as open system platform without modification.
Rehosting a valuable legacy system can be viewed as risky by managers who are unfamiliar with TmaxSoft's sophisticated rehosting software and our experience in safely rehosting large-scale enterprise systems. Some of the typical questions that managers considering rehosting ask TmaxSoft are detailed below:
YES!
TmaxSoft recognizes that the applications and data residing within the typical mainframe-based legacy system, having been updated and modified over a period years or decades, and therefore form an integral part of a company's competitiveness. One goal of rehosting is to ensure that the functionality of the original system is conserved during the migration process.
TmaxSoft and OpenFrame ensure that application and data integrity is conserved during the migration process through two main approaches:
1. OpenFrame provides a range of tools and utilities that largely automate the actual migration process and ensure that human errors do not corrupt the client's valuable application logic or data.
2. OpenFrame incorporates a range of modules that enable the various mainframe resources to operate within the open system without modification. This enables our clients' mainframe applications to be migrated to OpenFrame-based systems entirely logic-intact.
YES!
Middleware is the key factor in determining a system's performance and stability. OpenFrame is based on powerful, market-verified middleware platform. Thus, OpenFrame facilitates and oversees transaction processing in distributed systems made up of multiple real or virtual machines (nodes). OpenFrame also maximizes transaction processing efficiency and provides a transparent view of the workflow within distributed system environments.
OpenFrame provides a robust set of features that maintain system stability and ensure that large volumes of transactions can be processed quickly and reliably at all times. For example, load balancing features enable OpenFrame to monitor the system and funnel transaction requests to certain nodes in order to optimize overall system efficiency. Additionally, fault tolerance features enable OpenFrame to monitor system components and re-route transaction requests, or restart system components to handle system or network errors.
Also, because the middleware technology at the core of OpenFrame was originally developed for unifying large-scale, distributed enterprise systems, OpenFrame can handle a wide variety of interfaces and protocols for connecting the main system to peripheral components and other systems. Thus, OpenFrame-based systems can connect to virtually any external tool, program, or system without requiring the modification of applications.
YES!
Online applications (applications developed for use within the CICS and IMS regions of mainframes) typically perform better within open systems. However, it is difficult to run JCL (for performing Batch tasks) within non-mainframe environments. This has resulted in other rehosting vendors having to convert their clients' JCL into inefficient UNIX scripts. On top of this, Batch applications are often written inefficiently in terms of input-output requirements. This can mean that they perform more slowly when exported to open systems, due to the architectural differences between mainframes and open systems (which are typically distributed systems).
TmaxSoft and OpenFrame resolve these two issues through two separate methods. First, OpenFrame incorporates powerful JCL processing engines that are capable of running JCL applications without modification within open systems. Second, TmaxSoft's system engineers have a great deal of experience in optimizing JCL for operation within open systems. TmaxSoft has developed a variety of automated functions and utilities, such as input-output buffering and data caching, which increase the input-output efficiency of Batch applications when run within open systems.
YES!
On top of facilitating the migration of mainframe legacy system applications and data, OpenFrame provides a solid foundation for implementing SOA and other next-generation enterprise system concepts. For example, OpenFrame provides a more flexible system environment and increases system transparency, enabling clients to better respond to changes in business requirements or customer expectations.
In terms of next-generation concepts, OpenFrame supports a wide range of next-generation system environments and standards-based communication interfaces, including TCP, X.25, SNA Gateway, Java, etc. Additionally, OpenFrame simplifies the process of implementing a multi-layer architecture; streamlines the process of developing and integrating new applications; and increases the ease with which emerging technologies can be integrated into the system.
Furthermore, OpenFrame provides a transparent system development environment that conforms to X/Open DTP (Distributed Transaction Processing) standards. This facilitates efficient integration with WAS (Web Application Servers) and other technologies, enabling the system to quickly incorporate emerging next-generation concepts.
"TmaxSoft helped us to migrate our system from a mainframe platform to the open system using OpenFrame. Both TmaxSoft's experience from other rehosting projects and OpenFrame's technical sophistication were invaluable in ensuring that no unexpected issues emerged during the rehosting project.
This was by no means a simple project, in terms of the work force and time, but the rehosting was a great success. Indeed, the stabilization period was so short that other companies have requested to visit and benchmark the site.
By rehosting with OpenFrame, our system's processing of online transaction requests has improved by a factor of 3~4 during closing, our busiest period. Additionally, CPU usage during this period is only around 30%, showing that the system is extremely stable, even during peak periods. Furthermore, by rehosting with OpenFrame we have also been able to increase the number of simultaneous users from 50 to 250.
Thanks to the project, we are now able to provide reliable services even when the number of transaction requests increases rapidly, enabling us to provide seamless services 24 hours a day, 365 days a year. Furthermore, as moving to the open environment has enabled us to reduce our maintenance and other costs, we expect to start recouping the costs of the project within the year."
Kim Chang Sung
Senior Manager
Next Generation System Team, Meritz Fire Insurance
"The Mainframe Rehosting project at Samsung Life Insurance was a major success and realized multiple benefits for the company. The first among these was an expected operating cost reduction in excess of $20 million over a four year period, with the project break-even point coming at around 18 months. There were other benefits in the areas of scalability and flexibility. We were also able to further consolidate our datacenter environment towards our current standard platforms.
TmaxSoft performed a crucial role in this project with their OpenFrame/Online and OpenFrame/TJES products replacing CICS and JCL, respectively. Their ability to migrate existing online and batch applications with minimal modification was a key factor in the project's success. TmaxSoft displayed the highest levels of competence and professionalism in pursuing and resolving the various challenges that we faced."
Sang Ho Yoon
Director
Information Strategy Team, Samsung Life Insurance
