Many people consider Push an application specifically for the Internet. In fact, there is a growing number of corporations using Push as an Intranet application at the departmental level as well as corporation-wide. The Forrester Group predicts that by the year 2000, the enterprise market for Push will be approaching $300 million.

Why are Fortune 1000 companies turning to Push? Because it is much more than delivering CNN or Wired news to desktops. Serious Push is the proactive delivery of business-critical data to people who need to know and act. Knowledge workers are inundated with information, much of which is irrelevant to their work efforts. Yet among the mountains of data in e-mail, databases, the Internet and voicemail is information that could make them more efficient, productive and smarter in the execution of their work. Serious Push enables the right people to receive the personalized data that is critical to their work in real time: notification of low inventory levels, new client wins or losses, sales over a certain threshold for a product, high levels of support calls on a product or in a given area or automated competition tracking. Normally, users must look for this kind of data; Push enables its delivery to wherever they are working. Push technology enables the right data to find the right people at the right time.

And why is Java critical to application development in the Push market? Pushed data must be able to come from any back end source and reach any client or application on any platform. Obviously, Java and technologies like CORBA are particularly suited to development in an environment that requires support for multiple sources and platforms. The Push architecture you work with should be open on both the client and server sides. In BackWeb's case, Java developers can design applications that automatically receive live data via BackWeb channels. The data can then be manipulated and sent back upstream to a database or to another recipient. The data could be coming from databases via JDBC and the users identified via JNDI. Writing to Java APIs on the back end and pushing data to Java-based applications on the client side enables portability and scalability.

Using Java in the Push environment is also well suited to building strategies for rapid application assembly using components or applets. Charting, spreadsheet or OLAP functionalities can all be written as beans which can be snapped together and reused depending on the requirements of a given Push application. They may be used interchangeably to receive data through channels and present it in the most advantageous way. A component could also be used which allows users to prioritize where or how they want to be notified of critical data.

One of the primary advantages of Push in an Intranet environment is that it is a low cost way to ensure that software applications throughout the enterprise are up-to-date, including application code and Java applets or templates and graphic elements. For example, a database tracks the Java components that a given user needs to run a sales territory monitoring application. You don't want the user to have to wait for those components to download when the application is launched in a browser. Using Push technology, the applet components can be delivered automatically to the user before use so that they launch locally. If you are pushing software upgrades over your Intranet, it is critical that you can easily target specific groups of users. BackWeb, for example, provides a sophisticated, rules-based targeting system that allows software upgrades to be narrowcast to a specific group of users or even personalized for a single user. The targeting system could also be extended through a hook' to a database using JDBC or any other connectivity method, allowing personalization for unique users, as in our sales territory tracking example.

The ability to do differential downloads is a critical factor for implementing Intranet Push to deliver software and updates. Frequently, only a few class files in the application actually change, which is especially true of Java. It is much more efficient (and bandwidth-friendly) to push only the changed portion instead of the whole application. In addition, compressing the pushed content can save about 50 percent of the available bandwidth.

Since application distribution involves pushing a relatively large amount of data, it is very important that it has minimal impact on users' systems - it can't interrupt their work. And dial-up users need a way to complete downloads over multiple sessions without starting over each time. BackWeb calls this issue "politeness" and provides its Polite Agent technology for background, incremental downloading during a user's idle on-line time.

Scalability is another critical issue in implementing Intranet Push. If you have a one megabyte application and you want to push it to 100,000 users, you need a smart solution that will know to use multicasting to push the same content to many users, versus a "naive" Push solution that will move that one megabyte application 100,000 times - which would equal 100 gigabytes of data going over your network.

A well-designed Push infrastructure can be used to effectively deliver applications and a lot more. Polite Push is an ideal way to deliver rich, multimedia content. The user gets both high quality and immediate gratification since the delivery of the information is separated from its presentation - it is not displayed until fully downloaded.

It is evident that there are numerous technology benchmarks that separate serious Push solutions from the news delivery and Webcrawling technologies that gave birth to this market. The hype surrounding Push is beginning to subside and powerful applications are being built. Data will come from anywhere and must be able to reach any client, so Java is a perfect development environment for this exploding market. Push is fertile ground for Java developers seeking to build networked applications that make a difference in the way information moves through businesses.