NetSim – Introduction¶
Introduction to modeling and simulation of networks¶
A network simulator1 enables users to virtually create a network comprising of devices, links, applications, etc., and study the behavior and performance of the Network.
Some example applications of network simulators are:
Protocol performance analysis
Application modeling and analysis
Network design and planning
Research and development of new networking technologies
Test and Verification
The typical steps followed when simulating any network are:
Building the model: Create a network with devices, links, applications, etc.
Running the simulation: Run the discrete event simulation (DES) and log different performance metrics.
Analyzing the results: Examine output performance metrics such as throughput, delay, loss etc. at multiple levels - network, link, queue, application etc.
Developing your own protocol / algorithm: Extend existing algorithms by modifying the simulator’s source C code.
Versions of NetSim – Academic, Standard & Pro¶
NetSim is used by people from different areas such as industry, defense, and academics to design, simulate, analyze and verify the performance of different networks.
NetSim is available in three versions: Academic, Standard and Pro. The academic version is used for lab experimentation and teaching. The standard version is used for R&D at educational institutions while, NetSim Pro version addresses the needs of defense and industry. The Standard and Pro versions are available as components in NetSim v15.0, which users can select and assemble. A comparison of the features in the three versions are tabulated below Table 1‑1.
| Features | Academic | Standard | Pro |
|---|---|---|---|
| Technology Coverage | |||
| Internetworks | Yes | Yes | Yes |
| Legacy & Cellular Networks | Yes | Yes | Yes |
| Advanced Routing | Yes | Yes | Yes |
| Mobile Adhoc networks | Yes | Yes | Yes |
| Software Defined Networks | Yes | Yes | Yes |
| Wireless Sensor Networks | Yes | Yes | Yes |
| Internet of Things | Yes | Yes | Yes |
| Cognitive Radio Networks | Yes | Yes | Yes |
| LTE Networks | Yes | Yes | Yes |
| VANET | Yes | Yes | Yes |
| 5G /6G | No | Yes | Yes |
| Satellite Communication Networks | No | Yes | Yes |
| Underwater Acoustic Networks | No | Yes | Yes |
| TDMA | No | No | Yes |
| 5G NTN | No | Yes | Yes |
Performance Reporting Performance metrics available for Network and Sub-networks |
Yes | Yes | Yes |
Packet Trace Available in tab ordered .csv format for easy post processing |
Yes | Yes | Yes |
Event Trace Available in tab ordered .csv format for easy post processing |
No | Yes | Yes |
Protocol Library Source Codes with Documentation Protocol C source codes and appropriate header files with extensive documentation |
No | Yes | Yes |
External Interfacing Interfacing with SUMO |
Yes | Yes | Yes |
| MATLAB | No | ||
| Wireshark | Yes | ||
Integrated debugging Users can write their own code, link their code to NetSim and debug using Visual Studio |
No | Yes | Yes |
Plots Allows users to plot the value of a parameter over simulation time |
Yes | Yes | Yes |
NetSim Animation Allows user to record and play the animation |
Yes | Yes | Yes |
| Simulation Scale | 100 Nodes | 500 Nodes | 2500 Nodes |
| Custom Coding and Modeling Support | No | Yes | Yes |
Emulator (Add on) Connect to real hardware running live application |
No | Yes | Yes |
| Target Users and Segment | Educational (Lab Experimentation) |
Educational (Research) |
Commercial (Industrial and Defense) |
A comparison of the features of NetSim Academic, Standard and Pro versions
Components (Technology Libraries) in Pro and Standard versions¶
Users can choose and assemble components (technology libraries) in NetSim Standard and Pro versions as shown Table 1‑2.
| Component No | Networks / Protocols Supported | Reference International Standards |
|---|---|---|
Component 1 (Base: Required for all components) |
Internetworks WLAN - 802.11 a / b / g /p / n / ac & e, Propagation models - HATA Urban / Suburban, COST 231 HATA urban / Suburban, Indoor Home / Office / Factory, Free Space, Log Distance. Shadowing - Constant, Lognormal. Fading - Rayleigh, Nakagami IPv4, Firewalls, Queuing - Round Robin, FIFO, Priority, WFQ, TCP - Old Tahoe, Tahoe, Reno, New Reno, BIC, CUBIC, Window Scaling, SACK UDP Common Modules Virtual Network Stack, Simulation Kernel, Command Line Interface Command Line Interpreter Metrics Engine with packet and event trace Plot Generator Packet Encryption External Interfaces: MATLAB, Wireshark Network Logs |
IEEE 802.3 RFCs 2453, 2328, 826, 793, 2001 and 768 |
| Component 2 | Legacy & Cellular Networks Aloha – (Pure & Slotted) GSM CDMA |
3GPP, ETSI, IMT-MC, IS-95 A/B, IxRTT, 1x-EV-Do, 3xRTT |
| Component 3 | Advanced Routing Access Control Lists, Detailed Layer 3 switch mode, Virtual LAN (VLAN), Public IP, Network Address Translation (NAT) |
IETF RFC’s 1771 & 3121 |
| Component 4 | Mobile Adhoc Networks MANET - DSR, AODV, OLSR, ZRP and OLSRv2 (add-on, PRO only) |
IETF RFC 4728, 3561, 3626 |
| Component 5 | Software Defined Network (SDN) | Based on Open Flow v1.3 |
Component 6 (Requires C4) |
Internet of things (IOT) with RPL protocol Wireless Sensor Networks (WSN) |
IEEE 802.15.4 MAC, RFC 6550 |
| Component 7 | Cognitive Radio Networks WRAN |
IEEE 802.22 |
| Component 8 | Long-Term Evolution Networks: LTE | 3GPP |
Component 9 (Requires C4) |
VANETs: IEEE 1609 WAVE, Basic Safety Message (BSM) protocol per J2735 DSRC, Interface with SUMO for road traffic simulation | IEEE 1609 |
Component 10 (Requires C3, C8) |
5G NR :3GPP 38 Series. Full Stack covering SDAP, PDCP, RLC – UM, TM, MAC, PHY – FR1 and FR2, mmWave propagation. | 3GPP 38.xxx |
Component 11 (Requires C3) |
Satellite Communication Networks: Geo Stationary Satellite. Forward link TDMA in Ku Band and Return link MF-TDMA in Ka band per DVB S2. Markov Loo Fading model. Device models for Satellite, Satellite Gateway, and Satellite User Terminals | DVB S2 |
Component 12 (Requires C2, C3) |
Underwater Acoustic Network: Acoustic PHY Model, Propagation based on speed of sound, Thorp propagation (temperature, depth, salinity), Slotted ALOHA in MAC, UDP in L4, Underwater sensor application |
---- |
Component 13 (Requires C10) |
5G NTN: LEO/MEO/GEO single satellite simulation, Downlink transmission, Link budget calculations, Interference models, Feeder link and service link, Antenna Configuration, Frequence reuse: FR1 and FR3 Frequency bands: S-band and Ka-band |
TR 38.821 and TR 38.811 |
| TDMA Radio Networks Add on (Pro version only) | TDMA Radio Networks: Standard DTDMA, Interconnected DTDMA TDMA Link 16, Dynamic TDMA, Frequencies – HF, VHF, UHF Bands, Frequency Hopping |
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Network Emulator Add On (Interfaces with all components except C2) |
Network Emulator Connect real hardware running live applications to NetSim Simulator. IP based, data plane, flow through emulator. |
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Different Components (Technology Libraries) in Pro and Standard versions of NetSim