What is Jini

1
What is Jini?

• Jini network technology, or simply Jini, is based
  on Java and provides facilities for easily and
  immediately offering new services on a network.
  An example of such a service would be a printer
  service that makes a printer available to clients
  (users) on the network.

2
What is Jini?

• The Jini Programming Model
• Leases
• Distributed Events
• Transactions
• Lookup and Discovery Protocols
• Overview of JavaSpaces technology

3
The Objective

• When you walk up to an interaction device that is
  part of a system employing Jini technology, all
  of its services are as available to you as if
  they were on your own computer--and services
  include not only software but hardware devices as
  well, including disk drives, DVD players, VCRs,
  printers, scanners, digital cameras, and almost
  anything else you could imagine that passes
  information in and out. Adding a new device to a
  system employing Jini technology is simply
  plugging it in.

4
What are the advantages of Jini?

• Makes it easy to install and use services, and
  reduces operating costs for the following
  reasons
• It is easy to add and remove services.
• Services can be relocated on the network without
  affecting users.
• Services are available immediately and are found
  automatically.
• The Jini architecture is scalable.

5
Jini Services

• A Jini service is defined as an entity that can
  be used by a software program, a computer, a
  device, another service, or a human (via a user
  interface).
• Some examples of services are those that allow
  access to
• printers,
• databases,

6
Jini Services (Continued)

• software applications,
• devices such as cameras and home appliances,
• storage systems such as network attached storage
  appliances,
• CD burners etc.

7
What is Jini Connection Technology?

• Facilitates the following
• Distributed Computing
• Network Based Services
• Seamless Expansion
• Reliable Smart-Devices
• Ease of Administration

8
Requirements for Jini

• An infrastructure which operates as a dynamically
  distributed system
• A common language and implementation that enables
  low-overhead communication between distributed
  objects
• Lookup service
• Discovery/join protocol

9
Software Details

• Ties together machines on which Java programming
  language objects are running enabling them to
  work as a single powerful computer.

10
Technology Benefits

• Performance and Reliability gains from well
  established distributed computing platforms.
• Low impact method of customizing software and
  hardware configuration.
• Hot-plugging-all resources become available when
  plugged in .
• Ease of use reduces the need for administrators
  lowering ownership costs.

11
Jini Interoperability
12
Jini Interoperability(Continued)

• On the left is a device that needs a service
  performed, in this case a camera that needs to
  print a picture. The center represents the device
  that offers the service, in this case printing.
  The service typically will be performed locally
  but sometimes, as shown to the right, the service
  may either need to communicate with an external
  device, such as an older printer that does not
  support the Java programming language, or else
  bridge to a service not utilizing Jini connection
  technology, such as a database of images
  published to the Web.

13
Jini Interoperability(Continued)

• The arrows indicate the different levels of
  communication that are required. First, the
  camera locates the printer service by using Jini
  technology, which employs Java Remote Method
  Invocation (RMI), which in turn uses whatever
  network protocol is supported by the operating
  system. Jini technology does not require any
  particular operating system or network transport
  The camera may use infrared, radio, or be
  physically plugged in to the local network.