Node models

LAN Workstation: A client side workstation that use service provided by the network servers

LAN: a number of workstation inter-connected together via internal switch.

Server: a station that provide a special functionality or service (e.g. FTP server)

Router: represents a Cisco 7200 router that will run the several dynamic routing protocols.

Switch: represent Cisco 2900 switch used to connect routers with LANs.

Links: represent a communication link that inter-connects network nodes.

Application Definition: defines the different application such as HTTP, FTP, VoIP, etc…

Profiles Definition: describe the activity patterns of the user in terms of the used applications over a specific period of time. Some LAN maybe runs a particular profile while other workstations are running another profile; each has its own defined application.

Link Failure/Recovery object: used to fail links during the simulation in a given times as well as recovering them afterward.

Simulation design workflow

In order to build a network properly, a workflow steps must be followed, starting from creating the network models, secondly, choose data and statistics  to be collected and then run the simulation, finally, view and analyse the results. The figure below illustrate the workflow.

OPNET Architecture

OPNET Modeler provides a wide-range environment that support modelling, simulating and performance evaluation of vast types of networks. OPNET Modeler package comprises several tools, each one focusing on specific aspects of the modelling task. These various tools fall into three categories:

1.      Model Specification and Modelling Communications with Packets.

2.      Data Collection and Simulation.

3.      Analysis.

OPNET consists of three major components, Network Editor, Node Editor and Process Editor.

 

1. Project Editor: used to build the topology of a network and provide the basic analysis capabilities and simulation. Project Editor represents the geographical objects of the simulation and it has the ability to manage all network nodes such as routers, workstations and links. 
2. Node Editor: used to specify the device models’ structure. These models can be used in the Network Editor as node objects. For instance, Node Editor can be used to construct a packet switch defining its interfaces, switching speed ad all aspects and attributes involved in designing the node. 
3. Process Editor: used to specify the behaviour of process model using C/C+ language. Process models can be instantiate in Node Editor as processes. Processes independently execute threads that perform general communication and data processes functions. The functions can be represented either in hardware and software.

OPNET Introduction

Optimised Network Engineering Tool (OPNET) is a leading industry solution for modeling and simulation, it is based on Object-oriented modeling and support many types of networks and technologies. 

OPNET provide an effective way to design, simulate and dignoses many network types and offer a wide variety of services, application and managemnt features. OPNET has been used worldwide by companies, government, network equipment manufactures and network service providers as well as in education sector. 

OPNET has an extensive set of solutions packages, each of which support particular area, however, OPNET Modeler 16 will be used to conduct this projects.