Sun Java Enterprise System 2004Q2 Technical Overview |
Chapter 1
IntroductionSun Java Enterprise System is a software infrastructure that provides the services needed to support enterprise-strength applications distributed across a network or Internet environment. These applications are referred to in this book as distributed enterprise applications.
Java Enterprise System is also a Sun software release and delivery methodology and a business and pricing strategy. The focus of this book, however, is on Java Enterprise System as a software system.
This chapter introduces Java Enterprise System and the tasks involved in using the system. It covers the following topics:
Java Enterprise System ServicesToday’s business requirements demand software solutions that are distributed across a network or internet environment and have high levels of performance, availability, security, scalability, and serviceability. Java Enterprise System provides infrastructure services to support such software solutions.
These software solution are applications with the following characteristics:
- Distributed. The application consists of interacting software components deployed across a networked environment that might include geographically remote sites. These distributed components, running on the various computing nodes in the environment, work together to deliver specific business functions to end users and to other business applications.
- Enterprise-strength features. The application’s scope and scale meet the needs of a production environment or Internet service provider. The application typically spans an entire enterprise, integrating many departments, operations, and processes into a single software system. The application must meet high quality of service requirements regarding performance, availability, security, scalability, and serviceability.
Distributed enterprise applications require an underlying infrastructure that allows their distributed components to communicate with each other, coordinate their work, implement secure access, and so forth. This infrastructure consists of a number of distributed services.
These distributed infrastructure services are, in turn, supported by a hardware environment of computing nodes and network links. This environment includes SPARC and X86 (Intel and AMI) hardware architectures.
The overall scheme is shown in the following figure.
Figure 1-1 Support Needed for Distributed Enterprise Applications
Java Enterprise System provides the distributed infrastructure services layer shown in Figure 1-1. Java Enterprise System infrastructure services support a broad range of business services and applications. Among the infrastructure services provided by Java Enterprise System are the following:
- Portal services. Portal services enable mobile employees, telecommuters, knowledge workers, business partners, suppliers, and customers to securely access their personalized corporate portal from anywhere outside the corporate network through the Internet. These services provide anytime, anywhere access capabilities to user communities, delivering integration, aggregation, personalization, security, mobile access, and search.
- Communications and collaboration services. These services enable the secure interchange of information among diverse user communities. Specific capabilities include messaging, real-time collaboration, and calendar scheduling in the context of the user's business environment.
- Network identity and security services. These services improve security and protection of key corporate information assets by ensuring that appropriate access control policies are enforced across all communities, applications, and services on a global basis. These services work with a repository for storing and managing identity profiles, access privileges, and application and network resource information.
- Web and application services. These services enable IT organizations to develop, deploy, and manage applications for a broad range of servers, clients, and devices, based on Java 2 Platform, Enterprise Edition (J2EE) technology.
- Availability services. These services deliver a unique approach to application service-level management. Availability services provide the patented “Always-On” technology for application and web services, delivering near-continuous availability and scalability.
You can selectively deploy one or more of these infrastructure services, each of which might include a number of Java Enterprise System components.
Java Enterprise System ComponentsJava Enterprise System is an integration of previously independent Sun software products into a single software system.
The components of this system (the component products) have been tested together to ensure interoperability. Their integration is facilitated by a number of system-level features:
The main components of Java Enterprise System and the infrastructure services they provide are listed in the following table. For more details on any component, consult Java Enterprise System Server Components.
Working With Java Enterprise SystemCreating business solutions based on Java Enterprise System software involves a complex set of tasks that can be divided into three stages: requirements analysis, deployment, and operations, as shown in the following figure.
Figure 1-2 Solution Life-Cycle Stages
The Java Enterprise System life-cycle stages can be described briefly as follows:
- Requirements analysis. Translate an analysis of business needs into a deployment scenario: a logical architecture and quality of service requirements. The deployment scenario serves as a specification for a software deployment.
- Deployment. Translate a deployment scenario into a deployment architecture that meets business needs and can be used as a basis for project approval and budgeting. This architecture is also the basis for an implementation design that provides the details needed to build, test, and roll out into a production environment.
- Operations. Run a deployed software solution, monitoring and optimizing its performance and upgrading it to include new functionality as necessary.
The tasks involved in each of these stages are shown in Figure 1-2 and discussed more fully in Chapter 4, "Life-Cycle Concepts."
Figure 1-2 shows the kind of Java Enterprise System user needed to perform the various Java Enterprise System tasks. If you are working with Java Enterprise System, your job should fit one or more of the user categories shown in Figure 1-2. The following table describes the skills and background needed to perform the corresponding Java Enterprise System tasks.