Oracle9iAS Wireless Oracle Application Server Tips by Burleson Consulting

The Oracle9iAS Wireless component allows for wireless communications between remote wireless servers and the Oracle9iAS architecture. The core of Oracle9iAS wireless is the use of XML communications.  Oracle wireless transforms XML data into whatever markup language is used by the wireless system, including standard HTML, Wireless Markup Language (WML), and other special wireless markups such as VoiceXML and HDML.  This allows the application to generate one set of XML data that is reformatted for the presentation device, be it a cell phone, palm pilot or pager.

Wireless communications with Oracle is becoming commonplace because of the ubiquitous nature of Internet Service Providers creating wireless infrastructures (mostly in the major cities). Within these areas, Oracle wireless can be used to establish direct communications with Oracle9iAS using a standard J2EE and XML communications model.  Oracle9iAS wireless has the benefit is isolating the database communications from the complexity of the wireless protocol by encapsulating the communications into a separate, intermediate layer.

This is one of the most exciting components of Oracle9iAS because it holds the promise for wireless voice communications with Oracle database.  This technology could bring millions of end-user is far closer and intimate contact with their valuable data.

Oracle Reports Server

The Oracle Reports server component allows for the fast deployment of reports, documents and spreadsheets, all using data from the Oracle database.  To achieve this function the Oracle reports server must interface with an Oracle9iAS instance (and Oracle Portal) to manage the incoming report requests and send the completed reports back to the requesting user. To understand the Oracle Reports server, let?s take a simple example and following the report steps (figure 1.12).

• Invocation - The Reports server is invoked via the end-user entering a URL (or clicking a link on a web page).

• Routing - The Oracle9iAS instance intercepts the HTML or XML request, and directs the request to the Reports CGI (or Reports servlets).

• Request validation - Oracle reports then parses the HTML or XML request and determines the report and the security rules for the report.  If secure, Oracle Reports send an HTML page back to the end-user to accept a user name and password.

• Execution - The verified request is then queued for execution in the Reports server. Please note that you can configure multiple runtime engines for each reports server.

• Formatting - Upon completion of the execution, the Reports server formats the output as HTML and forwards the completed report to the Oracle9iAS instance.

• Delivery - The Oracle9iAS instance then completes the request by sending the completed report to the end-user.

Figure 12: The Oracle9iAS Report Server at runtime

Oracle9iAS Single Sign-On (SSO)

Single Sign-On (SSO) allows a client to sign onto the application once and be automatically authenticated for other components within the application server and also to external applications if properly setup.  SSO provides a central authentication repository rather than having a separate authentication for each application on the server.  SSO uses the Infrastructure instance to validate a user as they move from application to application without forcing the user to reauthenticate. 

The SSO component interacts with the Oracle HTTP Server (OHS) and allows the formatting of single sign-on information as an open-source Apache header.  It is important to note that SSO only functions within the domain of your Oracle system.  Many distributed eCommerce systems communicate with third party portals, and SSO cannot be extended to service these external clients.  For example, and Oracle eCommerce site might need to process a payment request with Cybercash, and Cybercash would require its own, independent SSO mechanism.  Hence, many Oracle9iAS administrators must develop XML Data Type Definition (DTD) protocols for communication with external third-party systems.

We will be discussing SSO and other components of Oracle9iAS security in great detail in Chapter 12, Oracle9iAS Security.

Oracle Internet Directory

The Oracle Internet Directory (OID) is a Lightweight Director Access Protocol (LDAP) directory service that provides centralized storage of information about users, applications, and resources in your enterprise. Coupled with SSO, OID allows end-users to sign-on one time and use their pre-defined OID credential (set-up by the DBA).  This credential defines those components of Oracle9iAS with which the end-user is allowed to interface.

Because it is LDAP-compliant, OID can be viewed as a simple lookup mechanism for web services.  For example, LDAP entries can be used instead of entries in the traditional tnsnames.ora file, thereby allowing connectivity for clients anywhere on your network.  This techniques has replaced the obsolete Oracle*Names tool as a method for defining services for Oracle.

In sum, OID is an easy-to-configure tool for defining end-user access with Oracle9iAS.  Because OID is tightly-coupled with SSO and Oracle advanced security, OID is a critical component is Oracle security management.

Management of OID is made quite simple with a GUI dubbed Oracle Directory Manager (ODM).  While we will be discussing ODM in great detail in Chapter 12, Oracle9iAS Security, for now you should know that ODM is a tool for the Oracle9iAS administrator to manage data access rules.

Metadata Repository (infrastructure)

The metadata repository is a critical component of Oracle9iAS because it allows for a common management interface between multiple instances of Oracle9iAS and the other components.  The metadata repository is commonly referred to as the infrastructure, and this is a critical common component to all Oracle9iAS farms and all Oracle9iAS components that share a common definition.  We will discuss the infrastructure in great detail in Chapter 3, Oracle9iAS Infrastructure.

Oracle Management Server (OMS)

The OMS allows the administrator to include the Application Server in centrally managed configuration using Oracle Enterprise Manager (a separate product).  OMS is a component of the Oracle Enterprise Manager (OEM) Console, and the OMS processes enable the management of the Oracle9iAS instances, databases, and other Oracle9iAS components. The foremost feature of OMS is its ability to store OEM data inside the metadata repository infrastructure.  This storage ability of OMS allows Oracle9iAS administrators to share server configuration information, scheduled Oracle9iAS events and jobs, and share notifications for Oracle9iAS failures.  To start OMS you use the emctl command and issue emctl start oms command to start the webservers and OMS processes.

Because OMS is the ?glue? that ties all of the Oracle9iAS components together, we will be visiting OMS functionality throughout this text.  OMS provides the important functions of user administration and manages the flow of information between the OEM console and all managed nodes.  OEM allows for any server to become a managed node by installing an Oracle intelligent agent (OIA), thereby making it accessible with the central administrative GUI.  An OIA is a daemon process that serves to interface with the database and operating system on each server within each Oracle9iAS farm.  The intelligent agent performs localized execution of tasks as directed by the OMS, and for Oracle servers, the OIA performs time-based database monitoring.  The concept of managed nodes allows ODM to become very powerful, allowing the Oracle9iAS DBA to quickly apply configuration changes to many server components.

This is an excerpt from "Oracle 10g Application Server Administration Handbook" by Don Burleson and John Garmany.