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.

  • Visualizing the simulation: Use the packet animator to view the > flow of packets.

  • 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 comes 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 v13.2 from which users can choose and assemble. A comparison of the features in the three versions are tabulated below Table 1‑1.

Features Academic Standard Pro
Technology Coverage
Internetworks Y Y Y
Legacy & Cellular Networks Y Y Y
Mobile Adhoc networks Y Y Y
Software Defined Networks Y Y Y
Wireless Sensor Networks Y Y Y
Internet of Things Y Y Y
Cognitive Radio Networks Y Y Y
LTE Networks Y Y Y
Satellite Communication Networks N Y Y
Underwater Acoustic Networks N Y Y
Performance Reporting
Performance metrics available for Network and Sub-networks Y Y Y
Packet Animator
Used to animate the packet flow in network Y Y Y
Packet Trace
Available in tab ordered .csv format for easy post processing Y Y Y
Event Trace
Available in tab ordered .csv format for easy post processing N Y Y
Protocol Library Source Codes with Documentation
Protocol C source codes and appropriate header files with extensive documentation N Y Y
External Interfacing
Interfacing with SUMO N Y Y
Wireshark Y
Integrated debugging
Users can write their own code, link their code to NetSim and debug using Visual Studio N Y Y
Allows users to plot the value of a parameter over simulation time Y Y Y
Simulation Scale 100 Nodes 500 Nodes ~ 10,0000 Nodes
Custom Coding and Modeling Support N Y Y
Emulator (Add on)
Connect to real hardware running live application N Y Y
TDMA Radio Networks (Add On)
Target Users and Segment Educational (Lab Experimentation) Educational (Research) Commercial(Industrial and Defense)

Table 1‑1: A comparison of the features of NetSim Academic, Standard and Pro versions

Components (Technology Libraries) in Pro and Standard versions#

Component No Networks / Protocols Supported Reference International Standards
Component 1(Base. Required for all components) Internetworks Ethernet - Fast & Gigabit, ARP, Routing - RIP, OSPF, WLAN - 802.11 a / b / g /p / n / ac & e, Propagation models - HATA Urban / Suburban, COST 231 HATA urban / Suburban, Indoor Home / Office / Factory, Friis 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 Traffic Generator: Voice, Video, FTP, Database, HTTP, Email, P2P, Custom, CBR. Virtual Network Stack, Simulation Kernel, Command Line Interface Command Line Interpreter Metrics Engine with packet and event trace Plot Generator Packet Animator, Packet Encryption External Interfaces: MATLAB, Wireshark IEEE 802.3 IEEE 802.11 a/b/g/n/ac/p/e RFCs 2453, 2328, 826, 793, 2001 and 768
Component 2 Legacy & Cellular NetworksAloha – (Pure & Slotted) GSM CDMA 3GPP, ETSI, IMT-MC, IS-95 A/B, IxRTT, 1x-EV-Do, 3xRTT
Component 3 Advanced Routing Multicast Routing - IGMP, PIM, 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 IETF RFC 4728, 3561, 3626
Component 5 Software Defined Network (SDN) Based on Open Flow v1.3
Component 6 (Component 4 required) Internet of things (IOT) with RPL protocol Wireless Sensor Networks (WSN) IEEE 802.15.4 MAC, MANET in L3 RFC 6550
Component 7 Cognitive Radio Networks WRAN IEEE 802.22
Component 8 Long-Term Evolution Networks: LTE 3GPP
Component 9 (Component 4 required) VANETs: IEEE 1609 WAVE, Basic Safety Message (BSM) protocol per J2735 DSRC, Interface with SUMO for road traffic simulation IEEE 1609
Component 10 (Components 8 required) 5G NR :3GPP 38 Series. Full Stack covering SDAP, PDCP, RLC – UM, TM, MAC, PHY – FR1 and FR2, mmWave propagation. 3GPP
Component 11 (Component 3 required) 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 (Component 2 & 3 required) Underwater Acoustic Network IEEE 802.11
TDMA Radio Networks Add on (Pro version only) TDMA Radio Networks TDMA Link 16, Dynamic TDMA, Frequencies – HF, VHF, UHF Bands,Frequency Hopping ----
Network Emulator Add On Network Emulator Connect real hardware running live applications to NetSim Simulator. IP based, data plane, flow through emulator. ----

Table 1‑2: Different Components (Technology Libraries) in Pro and Standard versions of NetSim

  1. To be technically precise, NetSim is an end-to-end, full-stack, packet level, continuous time, discrete event network simulator.