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  • INTRODUCTION
  • IMPLEMENTATION
  • RESULTS
  • ADVANTAGES

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    INTRODUCTION

     

     

                    IMMS (Integrated Materials Management System) is a Material Management software Application developed in a distributed RDBMS environment.  Oracle (ver 7.3) runs on RISC Servers at all project locations of ONGC.

     

                There are many transactional users of the system at the projects, such as stock-holders, C&F cell, Indentors, SLS cell, Q&A cell, Receipt cell etc.  MIS users such as Sectional heads, MM heads, RCMLO and ware-house in-charges were also accessing the database for various reports through the same package.

     

                At Client end, IMMS package is built on Oracle Developer tools. Oracle forms and reports runtime executables are required to be loaded at all client nodes.  Oracle SQL*Net configuration is also required to be set up at each client PC.

     

                As System Administrator, I was aware of the time and effort spent in each client PC in configuration.  I was therefore thinking of an alternate method of database access for MIS users, in particular, who would require faster access to inventory data from any client, which would entail minimum or preferably no configuration at client end.

     

                Speed of access was another factor. Oracle Developer components are memory intensive and due to underlying protocol, the time spent in getting connected to the SQL engine of server was very high. Additionally, there were many pre-form trigger codes executed, checking authorization etc, for the users.  Especially in case of accessing the database at other locations, (Say, Ankleswar or Ahmedabad from Mehsana) the time spent in accessing any inventory-related information was very high.

     

                Yet another issue was user-friendliness/ease of use of the Application.  Any custom application of such complexity as IMMS require at least 4to 5 days of training required to be imparted to the users.

     

                Web-enabling the application (I.e., accessing the IMMS database through a web browser software from client end) through use of Java servlets and jdbc connectivity was a very neat and economical solution to all three problems.  A paper was presented by me at Technology Meet 2001 conducted at Jodhpur, detailing the pros and cons of such a web-enabling and deployment of an Intranet.

     

     

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    IMPLEMENTATIION

     

     

                Since an Intranet facility is not yet operational in Mehsana project, it was decided to first set up a test Intranet facility using existing resources.

     

                A client PC available at IMMS server room was used for setting up the Intranet.  The Operating System on the PC was Windows 98 having PWS (Personal Web Server) built-in.  An IMMS web-site consisting of 3 to 4 web-pages (static content) was developed using Microsoft FrontPage Express and deployed on this PC.

     

                Since PWS does not support Servlet extension, a hunt was carried out in Internet for any free software. A Product called J-server was available which could be configured with any existing Web Server for providing servlet functionality.  A free test-deployment version was available for free downloading in Internet.  This product was used.

     

                PWS  listens at default http port 80 and J-server listens at port 8080.  Both these web servers were integrated so that both listened at default port 80, and PWS passed on requests containing servlets to the J-server.

     

                Odbc  (Open Database  Connectivity ) Protocol is an Industry protocol employed to integrate any platform specific application to access any database irrespective of the vendors.  Servlets can connect to databases through three different methods.  The easiest was through jdbc-odbc bridge driver.  So, for loading this driver, odbc was required to be first configured in the machine (web server).  Through ODBC configuration utility available in control panel, odbc System Sources were  configured for all three external (Ahmedabad, Baroda and Ankleswar)databases, in addition to the local database.  For clarity, the name of odbc system sources was kept the same as that of Oracle Name alias string.

     

                Jdbc-odbc bridge driver is supplied as part of jdk 1.3 and this was used.  As everyone would be aware, JDK is freely available for downloading from the site of Sun Java, for developing java applications/applets.  Latest version of JDK 1.3 was used to develop the servlet code.

     

     

     

     

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    RESULTS

     

     

                All three external databases and the local database have been configured for odbc access. Jdbc-odbc driver was loaded and all database connectivity tested and found okay.  So far, following information is dynamically generated as html page through local intranet.

     

    1. Quantity in hand of an item at all locations. For example, to know the quantity of all bearings, say at Ahmedabad project, an user has to click on Ahmedabad link and type %bearing% on the text-box provided and press Enter or ‘Submit’ button.  An HTML page is dynamically generated listing all items at all stock-points of Ahmedabad project along with present stock-on-hand.  Being web-page, this information can be saved in any format.

     

    1. Inventory Position at all locations.   Available as
      • Class-wise
      • All Stores classes
      • All Spare classes
      • Total of all classes – business group wise.

     

     

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    ADVANTAGES

     

    1. Absolutely, no client configuration is required.  Only requirement is connectivity to the web-server through LAN or WAN or dial-up., and any browser.  Internet Explorer is available built-in along with Windows operating system.  Many free web-browsers are available for downloading in Internet.
    2. Speed of retrieval of data is very fast, much faster than through IMMS Application, in view of TCP/IP protocol and odbc protocol used.
    3. Web pages are designed in a very friendly way to aid easy navigation. No applets are used.  JavaScript is used extensively for displaying user-alerts, mouse-over effects are employed to offer hints on links.
    4. Security is ensured through Java Servlets’ underlying security features and Oracle’s underlying security features.
    5. Cost incurred on this setup so far is zero, since existing hardware is used, and free software are used.
    6. This set up can be scaled upwards to cater to any number of users. Only Hardware would require upgrading.  It is proposed to use Linux O/s and Apache Web Server for this Intranet setup.  Both these software are in public free domain and open source.
    7. In existing IMMS set up, only Windows clients can be used.  In this setup any client (Linux/Macintosh/windows) can be used.  In fact, dynamic content in web-page also totally text-based, with little modification in servlet code, even PDAs or WAP enabled phones can access the server.
    8. Since only one web-server is deployed, any number of client PCs can be used to access the database through this web-server without worrying about the user-licenses of the Oracle Software.
    9. Since odbc protocol is used, even if underlying RDBMS is migrated to Oracle 8/8i or even other vendors such as IBM/Microsoft/Sybase, there would be absolutely no modification in code of servlets.
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