Jini: an overview Abdullah Akce Resul Ceylan

1. Jini: an overviewAbdullah Akce Resul Ceylan Background: visualparadox.com Abdullah Akce & Resul Ceylan

2. Outline • Technology overview • What is Jini? • What Does it Do? • Architectural overview • (How Does it Do?) • Conclusion Abdullah Akce & Resul Ceylan

3. Technical Overview > What is Jini? • Jini is a new distributed computing environment introduced by Sun Microsystems. • Its main goal is “network plug and play”. • It enables the building of • Dynamic • Flexible • Easily administered • distributed systems. • Jini is not an acronym, it does not stand for anything. Abdullah Akce & Resul Ceylan

4. Technical Overview > What is Jini? • When a new service is added to dynamic runtime environment; • It announces its presence. • If clients want to use that service; • it can locate it • it can use its available tasks. • Clients and services communicate with each other by Jini protocols. • Jini provides a middleware layer to link these services and clients. Abdullah Akce & Resul Ceylan

5. Technical Overview > What Does it Do? • Provides an application level abstraction of networking. • Client’s functional needs and service’s functional capabilities are defined in its simplest, flexible form. • It is used in wide range of applications: • Edge networking (recover failures at edges automatically) • Grid Computing (provides scalability) • Others (Dynamic System Integration, Dynamic Clustering, Workflow/Message Switching, Ad-hoc Networking, etc.) Abdullah Akce & Resul Ceylan

6. Technical Overview > What Does it Do? • Two examples: • Digital Camera and Printer Communication • Jini enabled desk lamp and alarm clock. Abdullah Akce & Resul Ceylan

7. Architectural Overview > How Jini works? a Jini device would automatically broadcast what the device it was embedded in could do and how it worked. Devices can link themselves and take advantage of each other's abilities, bypassing the need for a person to inform all the affected components. Source: ‘Sun tries again with Jini’, CNET News.com Abdullah Akce & Resul Ceylan

8. Architectural Overview > Components • It consists of three components: services, clients and the lookup service. There is a network connecting them. Abdullah Akce & Resul Ceylan

9. Architectural Overview > Registering a Jini Service A service is represented by a service object. It is the publicly visible part of the service and will be downloaded to clients. TheDiscovery Protocols are used to find out the lookup services. When lookup service gets a request, it sends an object called registrar back to the server. This object acts as a proxy to the lookup service. The Join Protocol happens after the discovery process, and is accomplished by using the downloaded proxy of the lookup service. Abdullah Akce & Resul Ceylan

10. Architectural Overview > Registering a Jini Service A service is represented by a service object. It is the publicly visible part of the service and will be downloaded to clients. TheDiscovery Protocols are used to find out the lookup services. When lookup service gets a request, it sends an object called registrar back to the server. This object acts as a proxy to the lookup service. The Join Protocol happens after the discovery process, and is accomplished by using the downloaded proxy of the lookup service. Abdullah Akce & Resul Ceylan

11. Architectural Overview > Registering a Jini Service A service is represented by a service object. It is the publicly visible part of the service and will be downloaded to clients. TheDiscovery Protocols are used to find out the lookup services. When lookup service gets a request, it sends an object called registrar back to the server. This object acts as a proxy to the lookup service. The Join Protocol happens after the discovery process, and is accomplished by using the downloaded proxy of the lookup service. Abdullah Akce & Resul Ceylan

12. Architectural Overview > Registering a Jini Service A service is represented by a service object. It is the publicly visible part of the service and will be downloaded to clients. TheDiscovery Protocols are used to find out the lookup services. When lookup service gets a request, it sends an object called registrar back to the server. This object acts as a proxy to the lookup service. The Join Protocol happens after the discovery process, and is accomplished by using the downloaded proxy of the lookup service. Abdullah Akce & Resul Ceylan

13. Architectural Overview > Using a Jini Service Abdullah Akce & Resul Ceylan

14. Architectural Overview > Camera/Printer Example Abdullah Akce & Resul Ceylan

15. Architectural Overview > Camera/Printer Example 1. A new printer is set up in the network. 2. The printer sends a “looking for lookup services” message to the local network. 3. Each lookup service on the network responds with a proxy for itself. 4. The printer registers its proxy object and attributes with each lookup service using the proxy of each lookup service. 5. A man with a digital camera comes into this network, and he wants to print out a new picture. 6. The camera sends “ looking for lookup services” messages to the local network. 7. Each lookup service in the network responds with a proxy for itself. 8. The camera searches for types of services it needs using the proxies of one or more lookup services. The lookup service returns one or more matching proxy objects, and the client distinguish them further by their attributes. 9. The exactly matched proxy is downloaded to the camera. Then the camera begins to use the proxy to interact with the printer to print the picture. Source: ‘The Jini Architecture’, Weisheng Si Abdullah Akce & Resul Ceylan

16. Thank you for your attention! The ENDAbdullah AkceResul Ceylan Abdullah Akce & Resul Ceylan