The PeopleSoft Internet Architecture (PIA) is a server-centric component architecture that enables secure end user access to PeopleSoft applications. Its components include the following:
• Internet Access Device
• Web Server
• Application Server
• Database Server
Each component fulfills a unique niche within the system, all of which are described in the PeopleSoft Internet Architecture Components lesson of this course.
With PIA there is no "traditional" client. Workstations simply need to have a supported browser installed. No other applets or connectivity software is needed on the workstation that runs the browser because all processing occurs at the server level. Dynamic HTML, rendered by the Application Server, is passed to the Web Server and sent on to a supported browser interface.
PeopleSoft Integration Technologies:
•Application Messaging - System-to-system communication.
•Component Interfaces - Transactions from external systems to PeopleSoft.
•Application Engine - Used in batch application processing.
•File Layouts - Used for integration with legacy systems.
PIA supports pure internet access for all PeopleSoft applications. It enables you to take advantage of all of the PeopleSoft intranet and internet solutions, as well as the PeopleSoft Integration Technologies, such as Application Messaging.
These technologies streamline integration of PeopleSoft applications with other PeopleSoft applications, custom internal systems, eMerchants, and customer trading partner systems. By supporting the open flow of information between systems, the PeopleSoft Integration Technologies provide true internet- based system integration.
The PeopleSoft Internet Architecture delivers intuitive, high-performance, HTML-based thin client applications that run on any machine with internet access. PIA deploys all transactions through a web browser.
Benefits of Browser-Based Deployment
•Minimizes the Training Effort
•Reduces Application Deployment Costs
•Lowers Client Hardware Requirements
•Allows Extensive Portability
There are two basic access methods with the PeopleSoft Internet Architecture:
(1) Directly, through a delivered homepage dedicated only to PeopleSoft applications, or
(2) Through a portal that may contain non-PeopleSoft content references.
Both of these deployment options are further discussed in the PeopleSoft Development and Deployment lesson of this course. Both options provide the benefits listed above of browser-based deployment.
Minimizes the Training Effort:
• Simple access
• Intuitive web look and feel
Less training is needed because most people with access to computers are very familiar with the look and feel of web pages, and know how to navigate within web browsers like Yahoo! and Amazon.com. End users just click a hyperlink to enter the PeopleSoft applications.
Reduces Application Deployment Costs:
• HTML-based for low bandwidth access
• HTML and JavaScript deployed to the browser
• No client installations required
Browser-based applications are easily deployed to end users.
By placing a hyperlink in an email or on a corporate website, users can access the applications just like they access any other website.
The cost of deploying browser-based applications is close to zero.
Lowers Client Hardware Requirements:
• Robust, scalable server-centric architecture
• Supports thousands of concurrent users
Because the browser-based applications put very small demands on the client machine, the end user does not need a high-end, expensive computer to use PeopleSoft applications. This means lower costs to customers, as they will not need to upgrade their client machines in order to use the latest PeopleSoft release.
Allows Extensive Portability:
• Web browser independence
• Client operation system independence
HTML browser-based applications are very portable across client operating systems. As long as the end user has a currently supported browser that is JavaScript 1.1 compliant, access to PeopleSoft applications can be through a Windows, Mac, Linux, or Unix client machine. From an end user's perspective, browser-based application deployment of PeopleSoft applications is cost-effective and easy to use.
Because PIA is completely server-based, client machines to this architecture can be nearly any kind of internet-enabled device, including:
• Web browser running on a PC or Macintosh
• Wireless device or cell phone
• External or third-party system
These devices use the standard internet technologies: HTTP, HTML, WML, and XML.
A web browser running on a workstation (client) using the HTTP protocol is the most common internet access. The browser does not download any applets nor does it require any plug-ins. Rather, a servlet installed on the Web Server facilitates all browser connections to the Application Server through JOLT.
When the browser sends a request to the Web Server, it is forwarded to the Application Server.
The Application Server sends only the following back to the browser:
• HTML
• JavaScript
• Cookies
The client workstation is free of any processing responsibility because there are no PeopleSoft executables on the client. This is why PeopleSoft Internet Architecture is termed an "architecture without a client."
With PeopleSoft Internet Architecture, only a single sign-in is needed between PeopleSoft databases. This is possible by leveraging Web Browser cookies that store a unique access token for users when they are initially authenticated. The token in the browser cookie is used to re-authenticate users when they connect to other PeopleSoft systems. This way, a user does not have to go through the sign-in process again. The browser cookie is stored in memory and never written to disk. It is encrypted by the Web Server and check-summed to prevent snooping and tampering.
As you can see, there is no "traditional" client involved in PeopleSoft Internet Architecture. The system sends pure HTML to a supported browser interface, while all processing occurs at the server level.The Web Server must be Java-enabled so that it can run the PeopleSoft-delivered Java Servlets that are installed as part of PeopleSoft Internet Architecture. One of these is the Portal Servlet, which relays all inbound and outbound transaction requests for the browser.
Using JOLT, the Web Server communicates browser requests to the Application Server. The pure HTML that the Application Server generates is formatted and presented in the browser by the Portal Servlet.
Together the Web Server and the Application Server make up the middle-tier of PIA; however, the Application Server does most of the work.
The Application Server is the core of PeopleSoft Internet Architecture. It handles messages from the Web Server through JOLT and executes all PeopleSoft business logic. In addition, it maintains the SQL connection to the Database Server for both browser requests and for the PeopleSoft development environment. PeopleSoft uses TUXEDO to manage database transactions.
At execution time, the Application Server fetches the most recent application definitions from the Metadata Repository of the Database Server. The Application Server caches the definitions in memory and executes the business rules, based on the definitions. Definitions such as pages, are created using the Application Designer tool in the PeopleSoft 8 development environment.
The Application Server consists of numerous PeopleSoft services and server processes that handle transaction requests. One of these server processes, PSAPPSRV, performs all application processing for a PeopleSoft internet session and generates the HTML to be displayed in the browser. For example, it is the PSAPPSRV process of the Application Server that builds and loads the pages which are then transmitted to the browser, as requested, through the Web Server.
As you can see, the Application Server is truly the heart of PeopleSoft Internet Architecture.
Just as in the PeopleSoft three-tier architecture, with the PeopleSoft 8 Internet Architecture, information is stored on the Database Server in three types of tables: System Catalog Tables, PeopleTools Tables, and PeopleSoft Application Data Tables. Each table type contains specific information that is related to running PeopleSoft applications.The PeopleSoft database is the repository for all information that is managed by PeopleSoft applications. Not only is application data stored in the database, but the PeopleSoft metadata is also maintained in the database. Metadata is what drives PeopleSoft Internet Architecture. Because PeopleSoft architectures have always been metadata-driven, PeopleSoft has been able to make the leap from client/server to internet-based applications without having to completely rewrite existing applications.
Several internet-related definitions were enhanced in PeopleTools 8.4 to enable full internet application development. These are the HTML Catalog, images, and style sheets. Just like fields, records, pages, menus, and other definitions, these definitions are stored in the PeopleTools Tables of the Database Server, and are fully upgradeable.
Multiple Application Servers can be connected to a single Database Server, which simultaneously handles the Application Server connections and development environment connections
No comments:
Post a Comment