What is IBM Service Management Framework Extension for Relocatable Services (ReSMF)?

IBM Service Management Framework^TM for Relocatable Services (ReSMF) is a framework for improving the availability and scalability of the services and hot-swapping of applications hosted in IBM Service Management Framework. It it built over the IBM Service Management Framework (SMF). SMF provides for the network delivery and management of applications and services independent of operating system and instruction set architecture (ISA). ReSMF enhances scalability and availability by facilitating policy-based stateful cloning and relocation of services and applications.

The relocation feature enables client applications that are built on ReSMF to float across devices (laptops, PDAs, smart-phones, etc.), providing uninterrupted user experience. This is significantly different from the current paradigm where an application has to be stopped on one device and started on the other with explicit synchronization of the application data.

ReSMF provides a hosting environment for relocatable services and applications; this environment is implemented as Mobile Services Framework (MoSeF). A service or appliccation can acquire relocation capabilities by being developed against the prescribed programming model. The relocatable services have various callback methods that are intercepted by the MoSeF, subsequent to which MoSeF takes control of their management.

How does it work?

The MoSeF environment notifies the services in its control about the changes in their local as well as global state by invoking suitable callback methods. It supports the additional primitives, such as move and clone, apart from the typical start, stop, and suspend and stop, which are applicable over hosted services.

In MoSeF, a normal service is transformed to a special class of service that is

• capable of finding other suitable and identical hosting environments in a defined domain
• capable of being mobile, whereby it can gracefully shut down from one hosting environment and relocate itself to another suitable environment along with its state
• capable of being cloned, whereby it can copy itself along with its state to another suitable hosting environment
• transparent to the consumer (of that service) as far as its location is concerned. This implies that even if the service might have moved to the new location (host), the consumer is able to work with it.

The advantages of MoSeF:

• The availability of services is improved because, in the event of adverse conditions in the current environment, services are able to autonomously migrate state-fully to another identical hosting environment.
• The scalability is improved because services can clone themselves onto identical environments.

Further information is available in this white paper.

Manu Kuchhal is a software engineer working with the Technology Incubation Centre at IBM Software Labs, India. Pervasive computing has been the area of major focus for Mr. Kuchhal. His current interests include mobile software agents, autonomic computing, grid computing, and peer-to-peer computing.

Umasuthan Ramakrishnan is a staff software engineer working with the Technology Incubation Centre at IBM Software Labs, India. He has been involved in the design and developmet of e-business applications over J2EE and Lotus Domino. Currently, his interests revolve around innovations in autonomic computing.

Umesh Joshi is a software engineer working at IBM Software Labs, India. He joined IBM in late 2003. He has about two years of experience in enterprise Web development and XML-related technologies. His current interests include grid computing.

Rohit Singh is a software engineer working with Websphere Data Interchange Team at IBM Software Labs, India. He has been involved in the testing of WDI and enhancement of testing tool for WDI written in Java. His current interests include grid computing and autonomic computing.