1. N.A.Shulver@staffs.ac.uk, J.C.Westlake@staffs.ac.uk Java for networking Module Introduction Data Communications Communication architecture Application interfacing – management, security, the Internet Network protocols Protocol stacks Wireless Networking Application development

2. N.A.Shulver@staffs.ac.uk, J.C.Westlake@staffs.ac.uk Java for networking Net-enabled Applications Objectives of this session:- Overview/History List the advantages of net-enabled applications Understand how object oriented technology can help with this type of application List technologies that make net-enabled applications possible List the capabilities of tools in developing this type of application

3. N.A.Shulver@staffs.ac.uk, J.C.Westlake@staffs.ac.uk Java for networking Overview 1 Basic networking facilities include “sockets” and “connection-based” or “connectionless” data routes There are various low-level protocols we can use with an appropriate language Java gives us access to low-level networking Great for stand-alone applications Great for less common Internet protocols

4. N.A.Shulver@staffs.ac.uk, J.C.Westlake@staffs.ac.uk Java for networking Overview 2 Network applications can run in a web browser These can be thought of as “self-service” applications they enable ‘things’ to be done from a web browser, e.g. online banking only skill required by user is the ability to use a browser Other examples: the review of books before buying, or a visit to a museum Great for piggybacking on standard (e.g. HTTP) protocols

5. N.A.Shulver@staffs.ac.uk, J.C.Westlake@staffs.ac.uk Java for networking Overview 3 Server-side applications can be very useful Early web users were limited to static HTML pages Useful for presenting company information often in a hierarchical manner but little or no interaction with the user Java applets addressed this problem enabling additional code to be downloaded, but still a problem of building customised information Dynamically generated HTML using the Common Gateway Interface (CGI) was an early solution

6. N.A.Shulver@staffs.ac.uk, J.C.Westlake@staffs.ac.uk Java for networking Overview 4 CGI was the forerunner for server-side Java based techniques Java Servlets JavaServer Pages (JSP) Component-based computing (Enterprise JavaBeans) Active Server Pages (ASP) Personal Home Pages (PHP) Visual Basic Web Classes

7. N.A.Shulver@staffs.ac.uk, J.C.Westlake@staffs.ac.uk Java for networking Web enabling techniques How to develop web-based applications and how can a server process multiple requests? - need a fast response Scalability - HTTP protocol - works in a stateless request-response mode - means it does not bind a server to a client for an inordinate amount of time There are a number of techniques which can be used to concurrently satisfy thousands of clients

8. N.A.Shulver@staffs.ac.uk, J.C.Westlake@staffs.ac.uk Java for networking Networking in Java Thus we may choose to use Java in a Web environment Or we may choose to do “bare metal” networking without using the higher-level Internet-style protocols In this module, we will look at both

9. N.A.Shulver@staffs.ac.uk, J.C.Westlake@staffs.ac.uk Java for networking Conclusion We will look at many aspects of networked applications Java is a useful tool to build applications at many different levels of complexity