Welcome to exteNd Composer and Telnet User Interface

Before You Begin

Welcome to the Telnet Connect Guide. This Guide is a companion to the exteNd Composer User's Guide, which details how to use all the features of exteNd Composer, except for the Connect Component Editors. If you haven't looked at the Composer User's Guide yet, please familiarize yourself with it before using this Guide.

exteNd Composer provides separate Component Editors for each Connect. The special features of each component editor are described in separate Guides like this one.

If you have been using exteNd Composer, and are familiar with the XML Map Component Editor, then this Guide should get you started with the Telnet Component Editor.

Before you can begin working with the Telnet Connect you must have installed it into your existing exteNd Composer. Likewise, before you can run any Services built with this Connect in the exteNd Composer Enterprise Server environment, you must have already installed the server-side software for this Connect into Composer Enterprise Server.

NOTE: To be successful with this Component Editor, you must be familiar with the Telnet environment and the particular applications that you want to XML-enable.

About exteNd Composer Connects

exteNd Composer is built upon a simple hub and spoke architecture (Fig.1-1). The hub is a robust XML transformation engine that accepts requests via XML documents, performs transformation processes on those documents and interfaces with XML-enabled applications, and returns an XML response document. The spokes, or Connects, are plug-in modules that "XML-enable" sources of data that are not XML aware, bringing their data into the hub for processing as XML. These data sources can be anything from legacy COBOL/applications to Message Queues to HTML pages.

HubSpoke

Figure 1-1

exteNd Composer Connects can be categorized by the integration strategy each one employs to XML-enable an information source. The integration strategies are a reflection of the major divisions used in modern systems designs for Internet-based computing architectures. Depending on your B2B needs and the architecture of your legacy applications, exteNd Composer can integrate your business systems at the User Interface, Program Logic, or Data levels. (See below.) Fred

What Is Telnet?

Telnet is a specification (RFC 854) for a communications protocol. The term Telnet refers to a generic TCP/IP protocol for emulating a terminal on ANSI standard systems. Many applications for UNIX and VAX/VMS (as well as others) were developed for terminal based systems. These systems allow remote execution of their interface through the Telnet TCP/IP protocol. Telnet allows this by mimicking the terminal in that it sends screens to a client and accepts keyed data from the client. This interaction, through a so-called "dumb" terminal, means that all the data is processed on the host computer. Telnet terminal emulation software can be used to make a microcomputer or PC act as if it were a Telnet-type terminal while it is communicating with a host computer.

What is the Telnet Connect?

The Telnet Connect XML-enables VT-series and ANSI Terminal based systems using the User Interface integration strategy by hooking into the Telnet Terminal Stream. Using the Telnet Connect, you can make legacy applications and their business logic available to the internet, extranet, or intranet processes. You can navigate through an application as if you were at a terminal session, use XML documents to drive inquiries and updates into the screens rather than keying, use the messages returned from application screens to make the same decisions as if you were at a terminal, and move data and responses into XML documents that can be returned to the requestor or continue to be processed. The Telnet screens appear in the Native Environment Pane of the Telnet Component Editor.

About exteNd Composer's Telnet Component

Much like the XML Map component, the Telnet Component is designed to map, transform, and transfer data between two different XML templates (i.e., request and response XML documents). However, it is specialized to make a connection (via Telnet) to a host application, process the data using elements from a screen, and then map the results to an output DOM. You can then act upon the output DOM in any way that makes sense for your integration application. In essence, you're able to capture data from, or push data to, a host system without ever having to alter the host system itself.

A Telnet Component can perform simple data manipulations, such as mapping and transferring data from an XML document into a host program, or perform "screen scraping" of a Telnet program, putting the harvested data into an XML document. A Telnet Component has all the functionality of the XML Map Component and can process XSL, send mail, and post and receive XML documents using the HTTP protocol.

What Applications Can You Build Using the Telnet User Interface Component Editor?

The Telnet User Interface Component Editor allows you to extend any XML integration you are building to include any of your business applications that support Telnet-based terminal interactions (See the exteNd Composer User's Guide for more information.) For example, you may have an application that retrieves a product's description, picture, price, and inventory from regularly updated databases and displays it in a Web browser. By using the Telnet Component Editor, you can now get the current product information from the operational systems and the static information (e.g., a picture) from a database and merge the information from these separate information sources before displaying it to a user. This provides the same current information to both your internal and external users.