Access NetSim from home via our cloud servers

What is the NetSim Cloud?

NetSim cloud is a hosted managed license server provided by Tetcos (developers of NetSim) to customers. There is no need for customers to any longer manage Dongles, MAC IDs, and other issues related to license servers.
In NetSim cloud, Tetcos’ manages the set of license server hosts which run the license server processes for our customers. It is a pure license-as-a-service offering, and there is no license server for customers to install.

How does it work?

You will receive a secure FTP download link for NetSim and a single license file. Each user of NetSim at your organization must download NetSim software and the license file. This is a common license file for all users.

Once NetSim is installed users just need to place the license file in the install directory of NetSim. Internet connectivity is required throughout the period of time users run NetSim.
The maximum number of simultaneous users is limited by the number of licenses purchased.

Can customers view their organization’s user’s license usage?

NetSim includes a Customer Portal to allow your customers to view their own licenses and servers associated with their organization.

How do I control access to NetSim?

The NetSim cloud portal provides customers with an option to edit the options file associated with any of their license servers. Options are provided to either allow (INCLUDE or INCLUDEALL) or disallow (EXCLUDE or EXCLUDEALL). INCLUDE or EXCLUDE can be done based on user, host, group, or IP address.

What happens if my organization’s users do not have internet connectivity?

In this case, you should plan to deploy a normal on-premises NetSim license server. Your software works completely locally if you desire.

Customers must choose prior to deployment, either cloud or on-premise license server option.

NetSim Example Experiments – Learn networking concepts

NetSim is a general-purpose network simulation tool used by 400+ customers world-wide; the focus is on ‘networking technologies and protocols’ and it is brand neutral. NetSim comes with a set of example experiments, to aid in the learning of networking concepts through simulation. Students can work remotely by accessing their University license server through VPN. These examples also have well-structured documentation covering Objective, Theory, Network Set-up, Results and Inference.

List of examples in NetSim

  • Introduction to NetSim
  • Understand the working of ARP, and IP Forwarding within a LAN and across a router
  • Simulate and study the spanning tree protocol
  • Introduction to the TCP connection management
  • Reliable data transfer with TCP
  • Mathematical Modelling of TCP Throughput Performance
  • Study how throughput and error of a Wireless LAN network changes as the distance between the Access Point and the wireless nodes is varied
  • WiFi: UDP Download Throughput
  • How many downloads can a Wi-Fi access point simultaneously handle?
  • TCP Congestion Control Algorithms
  • Multi-AP Wi-Fi Networks: Channel Allocation
  • Plot the characteristic curve of throughput versus offered traffic for a Pure and Slotted ALOHA system
  • Study the working and routing table formation of Interior routing protocols, i.e. Routing Information Protocol (RIP) and Open Shortest Path First (OSPF)
  • The M/D/1 Queue
  • Quality of Service (QoS) in 802.11e based WLANs
  • Analyze the performance of FIFO, Priority and WFQ Queuing Disciplines
  • Cyber Physical Systems (CPS) and IoT – An Introduction
  • One Hop IoT Network over IEEE 802.15.4
  • IoT – Multi-Hop Sensor-Sink Path
  • Study how call blocking probability varies as the load on a GSM network is continuously increased
  • Study the 802.15.4 Superframe Structure and analyze the effect of Superframe order on throughput
  • Understand the working of OSPF
  • Understand the working of basic networking commands (Ping, Route Add/Delete/Print, ACL)
  • Study how the throughput of LTE network varies as the distance between the ENB and UE (User Equipment) is increased
  • Study how the throughput of LTE network varies as the Channel bandwidth changes in the ENB (Evolved node)
  • Simulate and study LTE Handover procedure
  • Understand the working of LTE Device to Device Communication
  • Analyze how the allocation of the frequency spectrum to the Incumbent (Primary) and CR CPE (Secondary User) affects throughput
  • Understanding VLAN operation in L2 and L3 Switches
  • Understanding Access and Trunk Links in VLANs
  • Understanding Public IP Address & NAT (Network Address Translation)

To know more write to us at

Download the complete experiment manual from

New Release! – NetSim v12 with 5GNR mmWave Networks

5G Network in NetSim
5G Network in NetSim

Researchers lack the requisite tools for simulating end-to-end 5G networks. There are a few ‘Link-level’ simulators that enable users to model a single link between the UE and the gNB. These can’t be used for end-to-end modeling of the network, from the UE to the host-server. Furthermore, they do not allow for modeling of the entire TCP/IP protocol stack. Open source simulators are very complex, do not have a GUI, not easy to use, require the knowledge of various scripting & programming languages, and come with no support. Hardware test-beds that can be customized are prohibitively expensive. NetSim solves these problems.

NetSim v12 with new 5G library is an end-to-end, full-stack, packet-level simulator and features an easy to use GUI with simple drag and drop functionality. The output of the simulation is available as an appealing Results Dashboard with tables and graphs. Protocol source C code is provided along with which can be modified by researchers to write their own algorithms/protocols.

The 5G library is based on Rel 15 / 3GPP series-

  • The 5G library in NetSim models all layers of the protocol stack as well as applications running over the network. It provides integration with TCP/IP stack protocols, Wireless protocols, Routing, Mobility, Output Metrics, Animation, Traces etc.
  • NetSim allows for end-to-end connections between UEs and remote hosts over IPv4. The 5G network can be connected to the core using the device “EPC”. Any regular NetSim application (FTP, Voice, Video, etc) working over TCP/UDP can be simulated.
  • The fundamental unit used for resource allocation is one Resource block (RB). This allows the user to accurately model packet scheduling.
  • NetSim can scale up to 100’s of UEs and gNBs. At this scale, it becomes impossible to model the radio interface at a granularity of one symbol, due to the computational complexity. In fact, it is for this reason that link-level simulators are limited to a single gNB and one or few UEs.
  • IP packets arriving from upper layers are segmented by the RLC entity into RLC DUs. The and Radio resource management functions work with these RLC SDUs. At the receive side, the RLC SDUs are concatenated into IP packets.

5G Library features

  • SDAP (Based on specification: 37.324)
  • RLC (Based on specification 38.322)
    • TM (Transparent Mode)
    • UM (Unacknowledge Mode)
    • AM (Acknowledge Mode)
  • PDCP (based on Specification: 38.323):
    • Transmit PDCP SDU
      • Sets the PDCP Sequence Number
      • Adds RLC Header
      • Calls RLC service primitive
    • PDCP Association: UE association/dissociation with gNB
    • Maintenance of PDCP sequence numbers
    • Discard Timer
    • Transmission Buffer
    • PDCP Entity
    • t-Reordering Timer
    • Receive buffer
  • MAC Layer
    • Transparent MAC
    • Mapping between logical channels and transport channels
    • Multiplexing and demultiplexing of MAC SDUs from one or different logical channels onto transport blocks (TB) to be delivered to the physical layer on transport channels
  • PHY Layer
    • Supported transmission numerologies µ = 0, 1, 2, 3, 4
    • The FR1 bands implemented in NetSim are those that run TDD in Duplex mode, namely n34, n38, n39, n40, n41, n50, n51, n77, n78 and n79
    • The FR2 bands in NetSim are n257, n258, n260 and n261
    • CQI reporting, CQI-MCS
    • MCS-TBS
    • Uplink and downlink physical channel
    • Frame structure and physical resources
    • Modulation mapping: BPSK, QPSK, 16QAM, 64QAM, 256QAM
    • Physical shared channel in uplink and downlink
  • mm-Wave Propagation models (Based on 3GPPTR38.900)
    • Environment
      • Rural Macrocell
      • Urban Macrocell
      • Urban Microcell
      • Indoor Office – Mixed office, Open office
    • UE Position
      • Indoor
      • Outdoor
    • LOS State
      • LOS (Line of Sight)
      • NLOS (Non-Line of Sight)
    • Outdoor to indoor model
      • High-loss Model
      • Low-Loss model

View Demo

Write to us for more information about functionality, upgrades, pricing, or a demonstration!
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What’s new in the latest release of NetSim™ (ver 11.1)

New Release NetSim v11.1

New and enhanced features in NetSim (v11.1)

NetSim is the industry’s leading network simulation software for protocol modelling and simulation, network R & D and defence applications.
It is an end-to-end, full stack, packet level network simulator and emulator, providing network engineers with a technology development environment for protocol modelling, network R&D and military communications. The behaviour and performance of new protocols and devices can be investigated in an virtual network within NetSim at significantly lower cost and in less time than with hardware prototypes.

The Apr 19 release of NetSim (ver 11.1) rolls out exciting new features focused on enhancing usability:

  • Introducing Workspaces in NetSim – More freedom and flexibility
    • Users can group together NetSim source code, binaries, libraries, experiments and images related to one project
    • Export/import workspaces and export/import experiments
    • A single PC/VM and license can be used effectively by multiple users each of whom can independently modify the underlying source code
  • Building and linking your own code is now a breeze
    • Single click to open protocol source codes
    • Manual, complex and time-consuming tasks related to development environment, dependencies and compiler eliminated
    • Write your own code and simply build – NetSim will automatically simulate per your code
  • Understand NetSim internals through example simulations
    • 40+ examples
    • Ready to simulate scenarios to understand the working of different protocol/technology libraries in NetSim
  • Learn networking concepts through sample experiments (for Edu customers)
  • Benefit from well-structured documentation
    • User manual plus 13 technology library manuals
    • Sectioned as Simulation GUI, Model Features, Featured Examples and Reference Documents
    • 250 + Q & A available in our knowledgebase –

Please contact us for more information about functionality, upgrades, pricing, or a demonstration!

Accelerate R&D in Vehicular Adhoc Networks (VANETs) using NetSim v11.1

A Vehicular Adhoc Network (VANET) is a network that provides communication between moving vehicles (V2V) and infrastructure (V2I). VANETs are a rapidly emerging research topic. However, VANET field testing is extremely expensive, time-consuming and practically challenging. NetSim addresses these concerns by allowing users to
create and analyze real-world conditions within the simulator. IEEE 1609 defines the architecture and provides the standards for Wireless Access in Vehicular Environments (WAVE) that defines vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) wireless communications.

NetSim allows for VANET simulations per MAC/PHY standards defined in IEEE 802.11p, IEEE1609 WAVE and LTE.

NetSim™ – SUMO Interfacing

Simulation of IEEE 1609 WAVE based VANET Networks can be achieved by interfacing NetSim with SUMO (Simulation of Urban Mobility), an Open Source traffic simulation software. Users can model the number of vehicles, the direction and velocity of their movement, the features of the wireless network transceivers, the routing protocol,
etc. During simulation NetSim gathers data about the network to measure protocol performance. This includes application throughput, link utilization, packet delays, packet errors, packet delivery ratio etc.
Moreover, it is possible to visualize mobility & communication in VANET using NetSim animator.
These VANET simulation features would be useful to engineers & researchers working on the communications architecture for DSRC – based V2V and V2I interactions.

Other External Interfaces

  • MATLAB and Simulink
  • Python
  • Wireshark for packet capture and analysis
  • NetSim Emulator to connect simulator to real devices

VANET Research Work-flow using NetSim™

VANET Research Work-flow using NetSim™
VANET Research Work-flow

VANET Network Stack

Application Layer

  • Basic Safety Message (BSM) Protocol as per standard J2735
  • Dedicated Short Range Communications (DSRC) Message

Transport Layer

Wave Short Message Protocol (WSMP)
* WSM Transmission
* WSM Reception
* Service Requests and Channel Access Assignment
* Service Channel (SCH) and Control Channel (CCH)

Network Layer

  • IPv4
  • Routing Protocols
    * DSR
    * AODV
    * ZRP
    * OLSR

MAC Layer

  • IEEE1609
    * Resource Manager – IEEE 1609.1
    * Network and Transport Services – IEEE 1609.3
    * Multi-Channel Co-ordination – IEEE 1609.4
  • IEEE802.11p
  • Protocol for QoS: IEEE802.11e

     PHY Layer

  • IEEE 1609
  • IEEE 802.11p for VANET but users can also use IEEE 802.11 a/ b / g / n / ac

RF Propagation Models

  • Path Loss
    * Friis Free Space Propagation
    * Log Distance
    * HATA Suburban, HATA Urban
    * COST 231 HATA Suburban, COST 231 HATA Urban
    * Indoor Office, Indoor Factory, Indoor Home
  • Shadowing Model
    * Constant
    * Lognormal
  • Fading Model
    * Rayleigh
    * Nakagami

NetSim Analytics

A variety of network performance metrics is reported including

  • Link Throughput
  • Packet Delay
  • Packet Delivery Ratio
  • Routing Overhead
  • IP Forwarding Table
  • Packet Retransmissions
  • Graphical plots over time … and more

Packet Trace: Users can log details of each packet as it flows in the network.

Event Trace: Users can log details of each event of the protocol FSM while execution of the discrete event simulation


VANETs based on LTE can also be simulated using NetSim. An example use-case is where vehicles use LTE to send/receive data to/from a remote server to make smart decisions regarding route planning and driving. A typical research problem would be to develop algorithms/architectures to ensure that the connection among vehicles and to the LTE infrastructure is ultra-reliable when the vehicles are moving at a high speed.


Key Research Areas

Some of the key research areas and challenges in VANETs are as under:

  • Quality of Service (QoS)
  • Efficient Routing Algorithms Design
  • Evaluation of New Communication Protocols
  • Network Attacks and Countermeasures

Read more…

WIT, Dehradun Leverages NetSim for R & D on Cognitive Radio Networks

NetSim for R & D on Cognitive Radio Networks

Cognitive radios allow the increase in the spectrum efficiency through flexible spectrum use. CR nodes can search for unused portions of the radio spectrum and communicate over those vacant radio frequencies.

Researchers at WIT, Dehradun, used NetSim to simulate cognitive sensing, i.e the CPEs (SUs) sense the spectrum and send periodic reports to the BS informing it about what they sense. The BS, with the information gathered, detects Primary User (PU) activity.

Challenge: Enhancing the efficiency of CR networks

Development of new sensing algorithms for better detection of primary users.

Use Case

Developing custom code: Users can write their own algorithms by modifying NetSim Source C codes. Some of the important files are 802.22.c, SpectrumManager.c, OFDMA.c, DSFrame.c, DSMAP.c, USFrame.c, USMAP.c and Incumbent.c.

Modeling network configurations: A variety of network configurations were created using NetSim’s GUI and XML based network configuration files. Simulation parameters were set per the experiment set-up.

Generating performance metrics: NetSim 802.22 library provides specialized output metrics such as Spectral efficiency, SCH sent/received, FCH sent/received, UCS sent, Primary User – Operational time, Idle time and interference time. Packet and event traces were also used for calculating the sought performance graphs.


Some examples of the publications completed using NetSim include –

  • Jyotsana Kanti, Ashish Bagwari, Geetam Singh Tomar, “Quality Analysis of Cognitive Radio Networks based on Modulation Techniques“, IEEE International Conference on Computational Intelligence and Communication Networks (CICN 2015)
  • Ashish Bagwari, Jyotsana Kanti, Geetam Singh Tomar, “Smart Detection Technique for IEEE 802.22 Standards“, Global Conference on Wireless & Optical Communications (GC WOC 18)
  • Ashish Bagwari, Jyotsana Kanti, Geetam Singh Tomar, “New Detector to Enhance Cognitive Radio Performances“, IEEE International Conference on Computational Intelligence and Communication Networks (CICN 2018)
    Based on the success of more than four batches of researchers, WIT in 2018, upgraded NetSim and purchased additional licenses to cater to the Research needs of for their Ph.D. Scholars.

“We evaluated other products such as NS-2, NS-3, Qualnet and OMNET but chose NetSim given its extensive R & D capabilities in 802.22 Cognitive Radio. In addition, the other simulators were too expensive with annual license purchases, support contracts etc.

NetSim source code is easy to understand and debug and NetSim is also well recognized in the research community. This coupled with onsite/helpdesk/phone-based technical support enabled us to publish our papers in time”

Dr. Ashish Bagwari
WIT, DehradunAshish BAghwari on Cognitive Radio in NetSim

Continue reading WIT, Dehradun Leverages NetSim for R & D on Cognitive Radio Networks

Simulate Internet-of-Things (IOT) using NetSim

How to simulate Internet-of-Things (IoT) using NetSim

NetSim GUI- Configurator

NetSim is a discrete event simulator covering a broad range of wired, wireless, mobile and sensor networks that comes with a user-friendly GUI which features. read on to get an idea of how IOT networks are simulated in NetSim..

NetSim IoT Design

  • Devices: Sensors, Cameras, 6LoWPAN Gateway, Routers, Switches, Access Points, Nodes etc. that can be dragged and dropped for network design
  • Data link and physical layer implementation as per IEEE 802.15.4 standard
  • Network layer support for both on IPv4 and IPv6
  • Adhoc IPv6 Routing support for AODV and RPL
NetSim Analytics Dashboard

NetSim Output Analytics

  • Results Dash Board to see the information at a glance
  • Packet and Event Trace with microsecond accuracy and tools to exploit the high resolution of network data
  • Packet Animator to see the flow of packets in the network
  • Visualization scripts for Route formation, Energy consumption etc

NetSim Applications

Know how NetSim is used for emulation of SCADA converged IP Communication networks for smart grids

R&D Projects with Source C Code and Documentation

Continue reading Simulate Internet-of-Things (IOT) using NetSim

Analyzing NetSim Packet trace using Pivot tables

NetSim Packet trace is saved as a spread sheet and can be converted to an Excel table to make the management and analysis of data easier. A table typically contains related data in a series of worksheet rows and columns that have been formatted as a table. By using the table features, you can then manage the data in the table rows and columns independently from the data in other rows and columns on the worksheet.

PivotTables are a great way to summarize, analyse, explore, and present your data, and you can create them with just a few clicks. PivotTables are highly flexible and can be quickly adjusted depending on how you need to display your results. You can also create Pivot Charts based on PivotTables that will automatically update when your PivotTables do.

Following are the steps to analyse the packet trace using pivot tables (using Excel 2013)

Step1. Click on a cell and then click on Format as Table

The Excel would ask you for the range of the data set and in general Excel would automatically choose till the last row, as shown below

Click OK and then the spread sheet will be converted to a table as shown below

Step 2. Next, from the Insert tab, click the PivotTable command.

Step 3. The Create Pivot Table dialog box will appear. Click on OK

Step 4. A blank PivotTable and Field List will appear on a new worksheet

Step 5. Once you create a Pivot Table, you’ll need to decide which fields to add. Each field is simply a column header from the source data. In the Pivot Table Field List, check the box for each field you want to add.

Step 6. If you want to analyse packets sent from all sources to all destinations, then check SOURCE_ID, DESTINATION_ID and CONTROL_PACKET_TYPE/APP_NAME.

Step 7. The selected fields will be added to one of the four areas below the Field List. Click SOURCE_ID, hold it and drag to the ROW field. Similarly, DESTINATION_ID to COLUMNS and CONTROL_PACKET_TYPE/APP_NAME VALUES

Step 8. The Pivot Table will calculate and summarize the selected fields. In this example, the Pivot Table shows the packets sent from all sources to all destinations.

Step 9. The above example shows all the packets which including data packets and control packets.

Step 10. If you wish to know how many were Data and how many were control packets then, check the PACKET_TYPE and drag it to the ROWS field

Step 11. This will look like

Step 12. Further, if you wish to know how many packets got errored and how many were successful, check the PACKET_STATUS field and drag it to the ROWS field.

Video: “How to analyze and visualize simulation output data in NetSim” is available at

For more information on NetSim please visit 

Interfacing NetSim with MATLAB

NetSim now provides users the ability to interface with MATLAB in run time

Underlying Theory:
MATLAB provides API’s to start and end the MATLAB process and send data / commands to and from MATLAB. NetSim runs these functions during initialization to simultaneously start-up a MATLAB process and whenever required send data to & from MATLAB in run time. NetSim ends the MATLAB process upon completion of the simulation.

Interfacing: An interfacing file named as NetSim_MATLAB_Interface.c is used to control the MATLAB computational engine and contains the functions –

fn_netsim_matlab_init() – which starts the MATLAB Process

fn_netsim_matlab_run() – which sends data to and from MATLAB, and sends commands to be processed in MATLAB

fn_netsim_matlab_finish() – which ends the MATLAB Process



Example of MATLAB call from WLAN PHY layer in NETSIM

Example Application: In this example, we replace NetSim’s default Rayleigh fading with the Nakagami fading model from MATLAB. Calls to the above functions are made at appropriate places in the NetSim code. So, for each packet, MATLAB calculates the Nakagami fading value in run time. This value returned by MATLAB is used by NetSim as the fading power instead of using the Rayleigh model. Note that instead of sending the commands directly from NetSim to MATLAB, we can also use a MATLAB .m file which will contain the commands to be executed by MATLAB.

Video: Interfacing NetSim with MATLAB is available at

IOT : Accelerate your research using NetSim C libraries

Research areas in IOT
  • Seamless integration of heterogeneous devices
  • Network architecture for IOT
  • Energy management and sustainable operation of IOT
  • 6LoWPAN based IOT design
  • Modeling and simulation of large scale IOT network
Write your own code
  • Create custom protocols using NetSim’s simulation API’s
  • Interface with other software products like MATLAB
  • Debug your code (step-in, step-out, step-over, continue) and watch your variables in sync with simulation
NetSim IOT features
  1. Create scenario , simulate and observe the performance of 6LoWPAN network
  2. Devices: Sensor Motes, 6LoWPAN Gateway, Routers, Switches, AP and Nodes can be used for the scenario building and simulation
  3. Data Link layer: Unslotted CSMA/CA, Slotted CSMA/CA, CCA
  4. Physical layer: Received Power Calculation, Fading, Shadowing, SINR calculation, BER calculation, Collision and error checking
  5. Sensor Mobility model, Sensing parameters, Packet generation, Packet Reception
  6. Radio Energy and Power Management
  7. Network layer can run both on IPV4 and IPv6
  8. Routing via AODV (RFC 3561), OLSR (RFC 3626), ZRP
  9. 6LoWPAN gateway will switch the packet from one network to another
  10. Facility to conduct various experiments for differing input / output parameters
  11. Input: Beacon Order, Super frame Order, Back off Exponent, Power Consumption, Battery life extension, CCA type, Receiver Sensitivity, ED Threshold, Channel Characteristics
  12. Output: Routing Overhead, Delay, Power Consumption, Lifetime of motes, Packet Delivery ratio, Routing Time, Actual Vs. Sensed path of agent

NetSim Emulator – Run live applications over virtual networks

Emulator_BlogWhat is a network emulator?
A NetSim emulator enables you to run real applications over virtual networks with wide selection of network conditions like error, delay, loss etc. Use of an emulator from development through pre-deployment phases obviates the need of redesigning, testing and tuning your applications, thus saving time, effort and eventually cost of setting up a network.

What you can do with NetSim Emulator?
• Network design and validation – Military radios, SCADA, Metro rail etc
• Application performance testing
• R&D in new protocol design
• Perform what-if analysis

What are the benefits of NetSim Emulator?
• Emulate a wide range of technologies – Switching, Routing, MANETs, Cognitive Radio networks, 4G-LTE networks, ZigBee networks
• A cost effective alternative to hardware emulators that have high costs and limited scale
• Reduced learning curve through agile testing in lab without complicated configuration

How does it work?
• Create the desired network in the Emulation server using NetSim GUI
• Run emulation client in the PC’s/VM’s where your live applications run
• Set the device IP addresses per the real PC/VM in the simulated network. Each live PC/VM corresponds to a node in the simulated network.
• Run your application and the emulation server
• Measure your application performance

You may view this introductory video on network emulation and how NetSim emulator works

Discrete Event Simulation and Event Programming in NetSim

The entire source code of NetSim is based on Event Programming since NetSim is a Discrete Event Simulator (DES)

Discrete-event simulation (DES), models the operation of a system as a discrete sequence of events in time. Each event occurs at a particular instant in time and marks a change of state in the system. Between consecutive events, no change in the system is assumed to occur; thus the simulation can directly jump in time from one event to the next.

Event-driven programming is a programming paradigm where flow of program is determined by different events. Thus, Event Programming is the favored method of coding a DES.

In NetSim there are different specific events and its sub-events
and the simulation kernel does the entire event handling. While, inserting an event into the kernel its event time should be mentioned since all events are executed in increasing order of their event time.

The link explains in detail how to model, run, visualize and analyze a Discrete Event Simulation of various networks.

NetSim wins award at IEEE COMSNETS 2015

We are happy to announce that NetSim was awarded the best demo runner up at COMSNETS 2015.


COMSNETS is a premier international conference dedicated to advances in Networking and Communications Systems. COMSNETS 2015 (Jan 6 – 10) featured a “Demos and Exhibits” session designed to allow start-ups, industries and researchers to showcase their latest industrial applications and research prototypes in all communications and networking related topics.

Beta version of NetSim v8.2 simulator and NetSim emulator were featured at COMSNETS. The emulator allows for connecting of real hardware running live applications to NetSim Simulator. The demo included emulation of video streams over wireless  (Wi-fi, LTE, Cognitive Radio etc) networks and compared source & destination streams (after simulating impairments via NetSim simulator). The packet captures of the two streams were available in hex format and difference between the captured packets & re-injected packets, after the network effects, were shown



Saastra University Leverages NetSim for Research on Securing Femtocells

Femtocells have been proposed as solution for high-speed mobile network (i.e. LTE) bandwidth requirements. In this paper, researchers try to identify and mitigate a possible attack in femtocells where locational information about a femtocell user is disclosed


Developing the Multihop Algorithm for privacy: An algorithm is to be developed to provide privacy to the sender which would require no additional hardware.

Simulating and Analyzing the algorithm: This algorithm should then be implemented into the device code, simulated and analyzed for performance.

Use Case

Developing custom code: Source C files, Cellular.c, GSM.c, Handover.c and GSM_Channel.c of NetSim’s GSM library were modified . These codes were linked and debugged using NetSim’s project work environment.

Modeling network configurations: Custom network configurations were created using NetSim’s XML based network configuration files. Alcatel Lucent home cell v2 was modeled with a radius of 25 meters and with 15 users.

Generating performance metrics: Packet and event traces were used for calculating the sought network performance metrics namely, Average Number of Reflections, and Average Time Spent in Femto Cell.


Statistically analyzing performance: Since the trade off of the algorithm was increased delay, this was studied and found to be approx 50 ms, which could be afforded by the network architecture
“We chose NetSim given its extensive R & D capabilities in MANETs, WSNs, Cognitive Radio Networks and Cellular networks. NetSim has an easy to use UI for creating scenarios and modeling protocol & device parameters. The protocol library source codes are written in C and easily understandable. NetSim’s product features and quick support from their technical team makes it easier to simulate complex networking protocols which results in publishing quality research articles”
Dr.V.S.Shankar Sriram,
SAASTRA University, Thanjavur
The published research paper is available at 

Please contact us for more information about functionality or pricing, or to arrange a demonstration.                                 Email:, Visit:

Simulation of LTE Networks in NetSim

LTE, an acronym for Long Term Evolution, commonly known as 4G LTE, is a standard for wireless communication of high-speed data for mobile phones and data terminals. It is based on the GSM/EDGE and UMTS/HSPA network technologies, increasing the capacity and speed using a different radio interface together with core network improvements.

  • NetSim LTE implementation is per 3GPP TS standards covering
  • Devices – User Equipment (UE), E-UTRAN Node B (eNB), Mobility Management Entity (MME)
  • Protocol Stack covering NAS (Non access stratum), PDCP (Packet data convergence protocol), RRC (Radio resource control), RLC (Radio link control), Concatenation
  1. Mapping between logical channels and transport channels
  2. Multiplexing of MAC SDUs from one or different logical channels onto transport blocks (TB)
  3. De multiplexing of MAC SDUs from one or different logical channels from transport blocks (TB)
  4. Priority handling between UEs by means of dynamic scheduling
  5. Priority handling between logical channels of one UE
  6. Logical Channel prioritization
  • LTE PHY – OFDM-MIMO Downlink and SC-FDMA uplink, CQI – SNR


The complete white paper explaining the implementation of LTE in NetSim and detailed comparison against NS-3 test suite is available at

LTE is available with NetSim v8 which is expected to be shipped from mid august ’14.

Please contact us for more information about functionality or pricing, or to arrange a demonstration. Email:, Visit:

Simulation of 802.11n and 802.11 ac based networks in NetSim

802.11n is an amendment to the IEEE 802.11 wireless networking standards to improve network throughput over the two previous standards—802.11a and 802.11g—with a significant increase in the maximum net data rate from 54 Mbps to 600 Mbps.

IEEE 802.11ac is the fifth generation in Wi-Fi networking standards and will bring fast, high quality video streaming with dramatic improvements in transmission speeds. Entry-level IEEE 802.11ac products will provide a data rate of 433 Mbps, which is at least three times faster than IEEE 802.11n and high-speed IEEE 802.11ac devices will offer wireless transmission in excess of 1 Gbps.
802.11n and 802.11 ac features in NetSim v8 (Beta)

Source C codes for 802.11 n and 802.11 ac are provided along with for user modifications

Please contact us for more information about functionality or pricing, or to arrange a demonstration.
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Static routing in NetSim

Static Routing

How to Setup Static Routes in RIP and OSPF

Step1 : In inter-networks, Static Routes can be set for any scenario having a minimum of 3 routers, 2 switches and 3 wired nodes. The easiest way to do this is to first run the scenario with routing protocol set as RIP/OSPF and save the Configuration file

Step 2 : Open the Configuration file with Visual studio. Expand the Router configuration and set the Static Routing information in Application Layer property of the device, by enabling the Static routing status. Then set the appropriate Static routing file name and file path.
By default:

Change to:

By default:

Change to:

1. Update this information in any one of the router
2. A sample StaticRouting.txt file will be available inside “C:\Program Files\NetSim standard\Docs\Sample_Configuration\Internetworks”. Appropriately modify it for the scenario.
The StaticRouting.txt file contains
1. Device Id of the Router
2. List of entries to add in the routing table
ip route [1]
ip route [1]
ip route [1]
ip route [1]

The above format is per standard Cisco command for static routes
ip route dest_ip mask gateway_ip [distance ]

1. The ip route is the Cisco command to add the static route
2. The dest_ip is the Network address for the destination network
3. The mask is the Subnet mask for the destination network
4. The gateway_ip is the IP address of the next-hop router
5. The distance is the administrative distance for the route. The default is 1 .

Step 3 : After this, run this configuration file through CLI and static routes will be used for routing.

How to fail a node in NetSim

In this section we explain node failure using MANET-DSR as an example

Using Device Id, Identify the Device ID of the particular device.

The fn_NetSim_DSR_Run( ) is the main function to handle all the protocol functionalities

DSR_Run( )

fp = fopen(pszFilepath,”r”);
while(fgets(pszConfigInput,500,fp)!= NULL)
sscanf(pszConfigInput,”%d %d”,&NodeArray[i],&TimeArray[i]);

for(i=0;i<100;i++) if((pstruEventDetails->nDeviceId == NodeArray[i])&&(pstruEventDetails->dEventTime >= TimeArray[i]))
// Node failure happens after a value of time storted in an array
{ // This just returns instead of running DSR functionality when the node is failed
pstruEventDetails->nInterfaceId = 0;
return 0;

Note: Add the above lines of code after the variable declarations in the function
Build the .dll by clicking Build ->Build Solution. (The dll will be created inside the Visual studio project->Debug)

Running NetSim via Command Line Interface (CLI)

NetSim provides options to run simulations via the GUI or via CLI. The CLI mode is preferred for automated execution (batch processing) of simulations. This feature is available from v7 onwards. In v7, NetSim can be run via CLI for Internetworks, Advanced Wireless Networks – MANET, Wireless Sensor Networks, Personal Area Networks and Cognitive Radio Networks only. For other networks NetSim v7 can only be run via GUI

Prior to running NetSim through command line interface (CLI), users must understand the following –
Step 1: App Path
App path is the file location in the system in which the NetSim7.0 has been installed.
The app path can be found out by right clicking the NetSim Shortcut in the desktop and selecting Open file location (In Vista and Windows 7) or Find Target (In Windows XP). The app path will be something like “C:\Program Files\NetSim Standard\bin”, depending on where NetSim is installed. The path to the bin folder of NetSim is termed as the app path.
Step 2: IO Path
IO path (Input/output Path) is the path where the input and output files of an application is
written. This is similar to the temp path of windows OS. For NetSim, the iopath is
%temp%/NetSim.  The Configuration.xml file for the scenrio to be simulated should be kept here prior to running the simulation. Note that the IO path must have write permission.
Step 3: Running NetSim through command line for Simulation
To run NetSim through command line, copy the app path where NetSimCore.exe is present and paste it in the command prompt. For floating/roaming licenses, type the following in the command prompt

>NetSimCore.exe<space> -apppath<space><app path><space>-iopath<space><io path><space> -license<space>5053@<Server IP Address>

<app path> contains all files of NetSim including NetSimCore.exe
<iopath> contains Configuration.xml and Configuration.xsd file
5053 is the port number through which the system communicates with the license server i.e  the system in which the dongle is running (for floating license users)
<Server IP Address> is the IP address of the system where NetSim license server (dongle) is running.

Sample configuration.xml files are available for Internetworks and Cognitive Radio Networks in the <apppath>/Docs/Sample_Configurations folder of the NetSim install directory. Rename the sample file as “Configuration.xml” before running NetSim through CLI. Depending on your system setting, the extension (.xml) might be implicitly present and not visible. In such cases do not add the extension, as that will cause the file to be named as configuration.xml.xml.

For node-locked licenses, type the following in the command prompt

>NetSimCore.exe<space> -apppath<space><app path><space>-iopath<space><io path><space>

Once Simulation is completed successfully and the metircs files that are requested by the end user in Configuration.xml will be written in the iopath. If any of the folder names contains white space, then mention the folder path within double quotes while specifying the folder name in the command prompt.

To know more about the options that are available to run NetSim via CLI, type the following in the command prompt.
>cd <app path>
>NetSimCore.exe -h

Adding Metric Variables in NetSim

There are two ways for you to get new Metrics in NetSim.

Option 1 (Easy): To get a “derived metric” from the existing NetSim output variables, then enable the packet trace & event trace and save them as XL files. Then use the XL UI or write VB scripts to get your derived metrics.

Option 2 (Hard): To get a completely new metric code will need to added in NetSim. An example is given below where new metrics have been added for LEACH (a new modification on the original DSR and code is available in a earlier blog entry) code,

Data_Packet_Received_PL is a new variable that has been defined in 802.15.4.h


_declspec(dllimport) POWER** pstruDevicePower;

//For LEACH/Data Metrics
// Array size is 101 since maximum number of sensors is 100 and 1 for sink

_declspec(dllimport) int Data_Packet_Sent_NWL[101] ;
_declspec(dllimport) int Data_Packet_Received_NWL[10] ;
_declspec(dllimport) int Data_Packet_Sent_PL[101] ;
_declspec(dllimport) int Data_Packet_Received_PL[101] ;
_declspec(dllimport) double Lifetime[101];

This is used in packetprocessing.c in the section

#ifdef _LEACH
if(pstruEventDetails->nDeviceId == pstruEventDetails->pPacket->nSourceId)
Data_Packet_Sent_NWL[pstruEventDetails->nDeviceId-1] += 1;
return 1;
#ifdef _LEACH

This variable after having been updated during the simulation in the section above, is finally printed in DSR.c as shown below

_declspec(dllexport) int fn_NetSim_DSR_Metrics(char* filename)
//This #ifdef…..#endif block defines the LEACH Metrics, which shows the packets
//sent and received by the Network Layer and the Physicaal Layer
//To enable LEACH, uncomment the line “#define _LEACH” in DSR.h
#ifdef _LEACH
FILE* fp;
int i;
fprintf(fp,”#LEACH Metrics\n”);
fprintf(fp,”DeviceID\tData Sent(Network Layer)\tData Sent(Physical Layer)\tData Received(Network Layer)\tData Received(Physical Layer)\tLifetime(sec)\n”);
for(i=0; i<NETWORK->nDeviceCount; i++)
return fn_NetSim_DSR_Metrics_F(filename);

If you face difficulty debugging code, please read the section in NetSim Help “Debugging when running NetSim via CLI (Only for Internetworks, Cognitive Radio
networks, MANET, Wireless Sensor Networks and Personal Area Network)”. Also ensure you are running as Visual studio in the administrator mode