Peer-to-Peer Programming on Groove

• Authors: James Edwards
• Venue: Peer-to-Peer Programming on Groove
• Year: 2002

From the Book:The Internet Web site webopedia.internet.com defines peer-to-peer architecture as "A type of network in which each workstation has equivalent capabilities and responsibilities. This differs from client/server architectures, in which some computers are dedicated to serving the others." But peer-to-peer is much more than a technology; it represents a radical change in how we will soon use our computers. It is, all at once, a revolution, an evolution, and a revision.It is a revolution because it turns today's current client/server architecture on its ear. Suddenly, we're all producers of information as well as mere consumers.Peer-to-peer computing is also a cultural revolution. Peer-to-peer technology will fundamentally change the way small groups work and interact over the Internet. By making it easy to find and download music over the Web, Napster not only has shown how fragile intellectual property rights of digital material are, but has probably affected the business model of the major media players, too.It is an evolution because the current state of software engineering makes possible distributed processing and storage across personal computers, as well as the first attempts to provide an operating system for the Internet.It is a revision because, in the early days of the Internet, peer-to-peer is how all computers were interconnected. The rise of the Web, with millions of people surfing, engaging in e-commerce, and downloading streaming video, made client/server architecture a really good idea.About GrooveGroove is an application that uses the Internet to make direct connections between members of a group. That group can consist offriends, family, co-workers, or any collection of people who want to communicate, solve problems, or work on a common task. Some of the functions of Groove let you talk, chat, send instant messages, draw pictures, share photos and files, play games, and browse the Web with other members of your group. With Groove, you communicate within secure, shared virtual spaces, in real-time, or in different places at different times. In addition, Groove is a platform that allows you to create, deploy, and run your own peer-to-peer applications.At the time of this writing, Groove runs only on PCs running the Windows operating system. These are the minimum requirements for installing and running Groove: A 233MHz Pentium processor or equivalent 64MB of RAM 40MB of available hard disk storage A 56kbps modem (DSL or cable modem preferred) Microsoft Internet Explorer 4.0 or greater (IE 5.0 or greater recommended) A sound card, speakers, and microphone, for using the voice features Updated minimum requirements are posted at www.groove.net/downloads/groove.Who Should Read This BookThis book is intended for those who want to develop peer-to-peer applications in Groove. The skills required to develop Groove applications include an understanding of the peer-to-peer paradigm, a working knowledge of extensible Markup Language (XML), familiarity with Open Software Description (OSD), and the ability to understand programming in JavaScript. Only the programming skill will be assumed—this book will help the reader develop the remaining skills. Information on these skills wi presented. The material is slanted toward intermediate programmers and advanced beginners but should be useful for advanced programmers with little prior knowledge of the peer-to-peer space.How the Book Is StructuredThe following 15 chapters give advanced beginner or intermediate programmers all the necessary background needed to understand the peer-to-peer paradigm, the Groove application, Groove architecture, XML, and OSD, as well as the ability to program and deploy an application on the Groove peer-to-peer platform: Chapter 1, "Why Peer-to-Peer?" explores the historical roots of peer-to-peer applications and discusses why peer-to-peer will be even more important in the future. Peer-to-peer applications are contrasted with client/server applications, highlighting strengths and weaknesses for various tasks. Chapter 2, "What Is Groove?" touches on the history of Groove—why and how it was developed. It describes the product and presents a case study of its use to solve an actual business problem. The chapter concludes showing why Groove is particularly useful to intermediate programmers or advanced beginners wanting to program in the peer-to-peer space. Chapter 3, "Exploring the Groove Application," exposes you to the Groove application. Detailed instructions for installing the application from the CD and a tour of Groove features let readers have the opportunity to experience peer-to-peer interaction. You will see and use some Groove tools similar to the ones you will soon be building. In Chapter 4, "Understanding Groove Architecture," you learn the concept of a shared space and the function of the Groov services that take care of security, persistence, and dissemination of data are explored so that you'll understand what services Groove provides. Component services are particularly covered so that you'll know how versioning and automatic dissemination of Groove tools—including tools you may build—takes place. Chapter 5, "Essential XML," presents the basics of XML as they relate to Groove operation and tool development. Chapter 6, "Essential OSD," explores the concept of Open Software Description. OSD provides an XML-based vocabulary for describing software packages and their interdependencies. With OSD, Groove provides the means for extending and updating the Groove application, including tools like the ones you will develop. Writing OSD is an essential step of tool development in Groove. Chapter 7, "Creating a Groove Development Environment," assists you in configuring your machines to easily develop Groove tools without affecting their capability to use Groove. You will verify that you have the applications you need to program Groove tools. All necessary applications are either included in system software or freely downloadable from the Net. Next, you'll learn how to reconfigure Groove to be able to safely build tools. Finally, we will walk you through the installation of the Groove Development Kit (GDK) and explore its contents. Chapter 8, "Customizing Groove," gives you the opportunity to create your own Groove skin. Creating a skin provides an easy entry into many of the concepts needed to develop Groove tools. In Chapter 9, "Building a Basic Groove Tool," a short discussion of the steps and elements neede is followed by a step-by-step tutorial. The tutorial begins the creation of a peer-to-peer trivia game tool, and addresses User Interface (UI), persistence, and dissemination issues. This part requires hand-coding of the XML for both understanding and experience. After an exploration of the tool descriptor, OSD, and .GRV files, Chapter 10, "Publishing a Basic Groove Tool," is a step-by-step tutorial on publishing the tool created in the preceding chapter. Chapter 11, "Easier Groove: The Tool Creator and Tool Publisher," introduces two tools supplied by Groove to make creating and publishing tools easier. You use these tools to finish the trivia game application. Chapter 12, "Easier Groove: Modifying the Basic Groove Tool with Tool Creator and Tool Publisher," is a tutorial that uses Tool Creator and Tool Publisher to modify and extend the trivia game tool and to republish it. Chapter 13, "Data Integration and Groove Bots," is a study of data integration in Groove through connectors and Groove bots. Data integration extends the reach of Groove tools by allowing them to connect with external information and applications resources. The chapter also covers some of the features and capabilities of bots and the Groove Enterprise Integration Server. Chapter 14, "Advanced Topics," continues the ongoing discussion of OSD, particularly redirection and directory structure strategies, and introduces some of the advanced features found in Groove. We explore Groove versioning and its implications for writing tools, and then talk about how to add roles and permissions to your tools, and how to provide overview and context help. We fin and how they can be used. In Chapter 15, "The Future of Peer-to-Peer," we make some guesses about how peer-to-peer applications will develop in the years to come, and examine the opportunities that will arise for peer-to-peer application programmers.If you're ready, let's get started!