5.13 Web Client Framework

Overview

The Web Client is built using technologies such as Struts, Tiles, JSTL, JSP & Servlet. It is designed based on the pull-MVC (Model-View-Controller) architectural paradigm, facilitating plugging in of user defined customizations. It is an interactive and user-friendly interface that helps accessing Web NMS through a Web browser and does not required any other resources on the client end.

Prerequisites

Knowledge of Struts Concepts and Tag Libraries

Note: During the Web NMS Server startup, the ActionServlet is instantiated. The requests sent from the browsers are handled by the ActionServlet, that is, the requests submitted causes the Web Container (default Web Container is Tomcat) to call the ActionServlet. Since we are using the Struts framework, the request contains a .do extension that maps to the ActionServlet. So, the .do extension is just a reference used for mapping, and is therefore, not a file type.

Struts, Tiles, Struts Validator, and JSTL

Jakarta Apache's Struts is an open source framework for building Java-based Web applications. It is based on the classic Model-View-Controller (MVC) design paradigm. It has its own 'Controller' component that receives browser requests and forwards them to the 'View' component.

The Web client uses two plug-ins with Struts: Tiles and the Struts Validator.

Web layouts are rendered using Tiles. It provide a framework for assembling presentation pages from component parts instead of using the conventional Frames. Each part ("Tile") can be reused any number of times.

The Struts Validator is used to perform form validation on the Web client. This facilitates easy validation of user input.

The JSTL or JSP Standard Tag Library is used by the Web client to encapsulate the core functionality common to many JSP applications, in the form of simple and standard tags.

Why Struts?

The Struts framework provides the following add-on facilities while customizing or building applications over the new Web Client.

Struts provides a powerful "action paradigm", instead of finding object-oriented abstraction. This provides the powerful Pull-MVC architecture, which simplifies web development.
Struts provides extensive taglibs ( html, bean,... etc) that enable easy page authoring and rapid development.
The Struts framework supports i18n and comes with a rich set of taglibs that complement Web NMS. In addition to this, JSTL tags are also used for internationalization.
Dynamic templating framework, namely Tiles, is available in Struts. This enables high customization of layouts.
Struts has a powerful Validator engine, which is not available in other frameworks. This facilitates easy validation of user input.

This extensive customizable enables smooth upgrade of Web Client framework. The JSP and configuration (XML) files can be customized and plugged in with different names. This enables hassle-free upgrade mechanism when applying Service Packs.

Key Features of Web Client

Highly usable, categorized & customizable. The rendering of Web NMS modules in tabbed panes facilitates easy navigation across the Web Client.
Appealing user interface with option to change its skins. The default implementations for skins is also provided.
Support for complete internationalization.
Fine grained web components such as Search, Tree, Calendar, Page Navigation.
No Frames; Tiles used for layout
Popup Menu and Column Customizer can be customized for user-defined modules.
The Authentication filter provides highly secure transactions while accessing resources.
The secured Web Client leverages the function of the Authorization Framework by checking the user privileges before allowing to execute an operation.

Module-wise Features

Module	Features
Smart View (Map)	Provision for pluggable Layout and Renderer mechanism. The Map module is facilitated with option to render Map views, in different layouts such as Ethernet, Grid, Star and so on. Customizable pop up menus. Map links displaying connection between network elements.
Fault Management (Network Events and Alarms)	Powerful functionality is provided to represent the Network Database, Events and Alarms as tabular views. Bulk operations such as bulk deletion, clearing and/or picking or unpicking of alarms can be performed. Categorized details form facilities performing operations on related alarms. The Alarm Count Category panel is a pie chart displayed for all modules, thereby enabling easy accessibility of network alarms. The page navigation component delivers an efficient way of traversing through the pages of the list view. The column customizer option, printing capabilities, and efficient sorting of the list view
Topology View	Operations such as manage, discover, delete, etc. can be performed over multiple Managed Objects. Object specific pop up menus are provided for the performing operations, seamlessly. Overall view of network such as viewing Events, Alarms and Reports can be performed through the pop up menus. Extendable Details Form for objects is provided. 'Search' option enables locating objects from the network database, effortlessly. The page navigation component delivers an efficient way of traversing through the pages of the list view.
Administration	New Web Client also includes options to perform the following administration tasks: User Admin Operations- Add/Modify/Remove Users, view User Details Network Admin Operations- Add a Node/Network, Refresh a Node Admin Operations- Shutdown Server, Backup, NE Re-sync after backup, NE re-sync Admin Configurations- Discovery Parameters, Discovery Criteria, Trap Parser, and Logging Details View- Viewing the details of BE Server, Scheduler, Port, FE Server, Client Details, and Server Logs
Reporting	The new reporting framework based on JFreeChart and JasperReports with high customizable and pluggable options. Default implementations of graphs for Receive Traffic, Transmit Traffic, CPU Utilization, Rx are provided. The default implementations of Utilization & Tx Utilization along with area graphs (using JFreeChart) & tabular view (using Jasper Reports) are also provided.
SNMP Tools	Enriched Mib Manager helps the network administrator load MIBs and query the devices directly. This user-friendly tool supports v1, v2c & v3 SNMP versions. Agents running in the devices can be queried directly using the pop-up menus from Map and Topology view. These user friendly tools are available out of the box for specific OIDs like routing table, TCP table, UDP Table, etc. SNMP tools can be configured to decide whether the device is to be reached via the back-end server or directly from the front-end server