There are three major components of a running Jini system: the “Jini Client,” the “Service Locator” and the “Jini Service.” “Jini Client” is anything that would like to use the Jini Service. The “Service Locator” is a locator, trader or broker that acts between the service and the client and also helps in locating services in a distributed Jini environment. The “Jini Service” is anything that can be used by client programs and also by other services.

The Jini basic architecture model can be conceptualized as a 5 layered model. The three major components (Jini Client, Service Locator, and Jini Service) lay on the uppermost layer of the Jini basic architecture model. The next layer below has the “Jini Technology.” The third layer has “Java Technology” followed by the fourth layer for the “Operating System.” The lowermost layer is the “Network Transport” layer.

The Jini technology “infrastructure” is comprised of the following services:

·         The Discovery and Join protocols

·         A Distributed Security system

·         The Lookup Service

The “discovery/join protocol” provides the technique by which any service becomes part of a Jini system. “RMI” (Remote Method Invocation) presents the base language for communication between Jini services. The implementation of the “distributed security model” defines the process for entity identification and the ways to obtain rights to perform actions on their own and for others. The “lookup service” presents the current members of the federation. It also acts as the central location for the federation members for offering and finding services.

The basic components of the Jini “programming model” are listed as under:

·         The “leasing interface” that defines a way of allocating and releasing resources using a renewable, time-specific model.

·         The “event and notification interface” that enables event-based communication between Jini services.

·         The “transaction interfaces” that enable entities to mutually work in such a way so that all of the group based modifications happen atomically, or none of them happens at all.