We faced so much difficulties in running Networking Simulators such as NS2, NS3, OPNET, and many more. Increasing Awareness and demand for stable simulator incorporates to other simulators, the OPNET simulator is one of the best solution. With the nays getting louder, the OPNET Modeler (similar to OPNET Simulator) is stronger competitor then other simulators.

1. OPNET
SIMULATOR
Parminder Singh
Assistant Professor| Chandigarh engineering college,landran
Singh.parminder06@gmail.com

3. PURPOSE
We faced so much difficulties in running Networking Simulators such as NS2, NS3,
OPNET, and many more. Increasing Awareness and demand for stable simulator
incorporates to other simulators, the OPNET simulator is one of the best solution. With
the nays getting louder, the OPNET Modeler (similar to OPNET Simulator) is stronger
competitor then other simulators.

4. OPNET Simulator vs OPNET Modeler
The OPNET Simulator kicked off the OPNET Modeler with a Technical preview aimed
squarely at Academicians, Researchers and Students.
The OPNET Modeler promised to develop wired and wireless networks as IPv4 with IPv6
addresses and other basic amenities excluding vehicular Ad-Hoc Networks.

5. OPNET Modeler
 OPNET Modeler is the commercial product that uses to modeling the networks.
 It incorporates distributed simulations.
 It has an enhanced GUI features, user friendly and make it easy to learn.
 It also support 32 bit and 64 bit fully parallel simulation.
 The Modeler supports many technologies including wired-wireless (LAN, MAN, WAN ),
Zigbee, Sensor Networks.
 It support number of Protocols such as OSPF, UDP,TCP, RIP and many more.

6. SIMULATION
 The Modeler support Discrete Event Simulation (DES).
 This DES Simulation is quite different from other simulation (used in many other
simulators) like time clocked simulation.
 The time clocked simulation processes every simulation in time-slots.
 The DES simulation processes every simulation in scheduled manner that means it
updates every event, also scheduled to simulate the next event.

7. HYBRID SIMULATION
 The advantage of OPNET Modeler is to support Hybrid simulation
 Many simulators does not support this sort of simulation.
 This simulation hold up background traffic and explicit traffic.
 The explicit traffic interprets the flow of packets in the entire network.
 The background traffic gauges power and memory requirement to run the individual
program.
 Besides explicit and background traffic, the simulator (NS2, NS3) only support explicit
traffic.

8. OPNET MODELER EDITORS
 The OPNET Modeler is to provide many editors for users to design the network.
 The Editor facilitates to modeling and simulating the network. Other than the editor also
provide Graphical User Interface.
 The 8 Editors listed in:
1. Project Editor 2. Node Editor 3. Process Editor
4. Link Editor 5. Packet Format Editor 6. ICI Editor
7. Packet Editor 8. Probe Editor

9. PROJECT EDITOR
 The most of Simulation and modeling done in this editor.
 TO open Project Editor in OPNET Modeler:
File menu--- New …..> Project
 To create new Project
Choose …> New Project

10. PROJECT EDITOR (cont..)
 The following advantage of Project Editor:
 Create and Edit Network Models.
 Manage Network Scenarios.
 Create and configure network topologies.
 Create and manage network traffic.
 Verify link connectivity

11. NODE EDITOR
 The Node Editor is the most powerful tool for create and edit the internal structure of the
node.
 The node composed of several modules.
 These modules can be used to transmit, store , receive, process and route the packets.
 The node itself belongs to switch, router, PC, or network.
 Select File Menu..> New and then choose Node Model.

12. PROCESS EDITOR
 It is the exact place where you can write code to implement Algorithms and Protocols.
 To select Process editor, Go to File menu ..> Select New..> Then choose process editor
from the number of options.

13. LINK EDITOR
The Link editor allow you to create and define links on the model.
This editor represented with physical connection between nodes.
When you make Physical connection then also define channel route, propagation delay,
error model, data rate and error correction.
To select Link editor, Go to File menu ..> Select New..> Then choose Link editor from the
number of options.

14. PACKET FORMAT EDITOR
 This Editor used to design the network model for transmission of packet.
 The packet generally categorized in two ways:
1. Formatted Packet 2. Unformatted Packet
 To transfer the actual packet with specified the name of the packet, destination node
etc., uses formatted packet.
 The unformatted packet give index to the packet, generally used in dummy packet.
 To select Packet Format editor, Go to File menu ..> Select New..> Then choose Packet
Format from the number of options.

15. ICI EDITOR
 The Interface Control Information (ICI) editor configure the internal structure of OPNET
modeling Scenario.
 The editor provide information to end user like: Inter-process communication, packet
size, information related to routed packet etc.
 To select Packet Format editor, Go to File menu ..> Select New..> Then choose ICI
Format from the number of options.

16. PDF EDITOR
 When you got data sequence from any proposed equation and see these data sequence
in graphical format . Therefore, you can choose Probability Density Function (PDF).
 To select PDF editor, Go to File menu ..> Select New..> Then choose PDF editor from
the number of options.

17. PROBE EDITOR
 A probe request by the user to collect a particular piece of data about a simulation.
 The user can customize the results according to the simulation statistics such as global
statistics, node statistics, link statistics, Path statistics etc.
 To select Probe editor, Go to File menu ..> Select New..> Then choose probe editor
from the number of options.

18. OPNET MODELER EXTENSION
 OPNET modeler includes node model, process model, link model, path model, network
model, packet format models and ICI format model.
 Models are saved in .m files.
 For a node model, the file extension is “.nd.m.”
 For a link model, the file extension is “.lk.m.”
 For a process model, the file extension is “.pr.m.”
 These editor files are saved in the model directory, which can be found from OPNET
Modeler:
 choose menu “Edit” – “Preferences” – search for “Model Directories.”

19. REFERENCES
[1] www.opnet.com
[2] http://www.riverbed.com/products/performance-management-control/opnet.html

20. Questions?
Singh.parminder06@gmail.com