Simulation GUI
In the Main menu select 🡪 New Simulation 🡪 Mobile Ad hoc networks as shown Figure-1
Figure-1: NetSim Home Screen
NetSim MANET Network Setup
Figure-2: MANET Network Setup window.
Deployment Architecture
The deployment options have been grouped into 2 categories. Standard MANET option where the scenario comprises only wireless nodes without any bridge node. Interconnected MANETs option allows users to connect two or more MANETs using a bridge node.
Standard MANET: In Standard MANET, a network scenario can be created using ad-hoc links and wireless nodes. Standard MANET supports DSR, AODV, OLSR and ZRP Routing protocols.
Figure-3: A Single MANET scenario.
Interconnected MANETs: In Interconnected MANETs, a network scenario can be created using multiple MANETs, bridge nodes for interconnecting multiple MANETs, and wired devices like switches, routers, and nodes. Interconnected MANETs support only DSR and AODV routing protocols.
Figure-4: Interconnected (Multiple) MANET Scenario
Fast Configuration
Figure-5: Fast Configuration window
The Fast Config window allows users to define device placement strategies and conveniently model large network scenarios especially in networks such as MANET, TDMA Radio Networks, WSN, UWAN and IoT. The parameters associated with the Fast Config Window is explained below:
Grid Origin: The 'Grid Origin' refers to the intersection point of the system's axes. NetSim supports any (X, Y) setting for the origin and not just (0, 0)
Grid Dimension: The width parameter represents the maximum extent along X from the origin and the height parameter represents the maximum extent along Y from the origin
Device placement area: The "Device Placement Area" allows users to specify the width and length of the area where devices are used when using the auto placement utility. This area must be less than or equal to the "Grid Area".
Device Placement
Automatic Placement
Uniform Placement: Devices are placed uniformly with equal gap between the devices in area based on the side length. This requires users to specify the number of devices as square numbers, such as 1, 4, 9, 16, etc.
Random Placement: Devices are placed randomly in the grid environment within the area based on side length.
File Based Placement: In order to place devices in user defined locations file-based placement options can be used. The file has the following general format:
<DEVICE NAME>,<DEVICE TYPE>,<X COORDINATE>,<Y COORDINATE>
Where,
DEVICE NAME – The name assigned to the device.
DEVICE TYPE – The unique device identifier specific to each type of device in NetSim.
Following table provides the DEVICE TYPE’s of all possible devices for networks with support for Device Fast Configuration:
NETWORK |
DEVICE_TYPE |
|---|---|
MANET |
|
WSN |
|
IOT |
|
Table-1: Fast Configuration window supports different networks.
X COORDINATE – The X-coordinate value of the device.
Y COORDINATE – The Y-coordinate value of the device.
Eg: MANET File-Based Placement.txt
Wireless Node Omni Antenna, WirelessNode,100,150
Wireless Node Omni Antenna, WirelessNode,150,100
Wireless Node Omni Antenna, WirelessNode,100,100
Wireless Node Omni Antenna, WirelessNode,50,50
Open NetSim, and in the Main menu, select New Simulation > Mobile Ad Hoc Networks. Select File Based Placement option under Automatic Placement and give the path of the text file as shown below Figure-6.
Figure-6: Device placement strategy to File based placement
After providing the path, clicking on OK will display the MANET network shown below, where all devices are placed as per the positions given in the text file as shown in Figure-7.
Figure-7: Network Topology
Number of Devices: It is the total number of devices that is to be placed in the grid environment. It should be a square number in case of uniform placement.
Manually Via Click and Drop
Selecting this option will load a link in the grid environment, where users can add devices by clicking and dropping them as required.
Create Scenario
Wireless Node
A MANET consists of mobile platforms -- simply referred to as "wireless nodes" in NetSim --which are free to move about arbitrarily. They are IP addressable devices. Wireless Nodes in NetSim MANETs library act as both end-nodes and routers. These nodes make routing decisions using the IP fabric.
In NetSim MANETs, each node can have only one wireless interface.
Bridge Node
Bridge Node acts as a bridge/interface/gateway between multiple MANETs. Packets from one MANET can be routed to another MANET via a Bridge Node as shown Figure-8.
Figure-8: Multiple MANETs connected via a Bridge node
Each Bridge Node has 24 interfaces. When connecting bridge nodes to one another or to routers, care should be taken to ensure that the static routes are set.
NetSim supports Wired and Wireless Bridge Nodes as shown Figure-9/Figure-10.
Figure-9: Two wired bridge nodes can be connected to each other using P2P wired links
Figure-10: Two wireless bridge nodes can be connected to each other using P2P wireless links
A wired bridge node cannot be connected to a wireless bridge node and vice versa.
Link
At a given point in time, depending on the nodes positions and their transmitter and receiver coverage patterns, transmission power levels and interference levels, wireless connectivity in the form of a random multi-hop graph or "ad hoc" network exists between the nodes. This ad hoc topology may change with time as the nodes move or adjust their transmission and reception parameters. Ad hoc links are used in NetSim to visually represent this connection of devices on an ad hoc basis as shown in Figure-11.
Figure-11: Mobile Ad hoc Network
Wireless links generally have significantly lower capacity than their hardwired counterparts. In addition, the realized throughput of wireless communications after accounting for the effects of multiple access, fading, noise, and interference conditions, etc. is often much less than a radio's maximum transmission rate.
Connecting ad hoc links is a one step process, by default one ad hoc link will be present in the grid. Users need to drop wireless nodes from the create scenario tab which gets automatically connected to ad hoc link.
An ad hoc link is a multipoint-to-multipoint link. When connected to a device its interface is set to 0 in NetSim.
Set Node, Link and Application Properties
Click on the appropriate node or link to open a right-side property panel. Then modify the parameters according to the requirements.
Global Properties: Certain properties are global in nature, i.e., changing properties in one node will automatically reflect in the others in that network.
In case of MANETs, in Wireless Nodes, Routing Protocol in Network Layer is global and all user editable properties in Datalink Layer, Physical Layer and Power are Local.
The following are the main properties of wireless node omni ant in Datalink and Physical layers as shown Figure-12/Figure-13.
Figure-12: Datalink layer properties window for wireless node omni ant
Figure-13: Physical layer properties window for wireless node omni ant.
Figure-14: Battery Model for Wireless node omni ant.
Configure an application between any two nodes by selecting any application from the Set Traffic tab. Click on the application will open a right-side property panel and set the properties according to the requirement.
Figure-15: Application icon and Configuration Window
Note: For MANET networks the application start time should be a min of 5s, since the amount of time is required for convergence of OLSR/ZRP.
Enable Packet Trace, Event Trace (Optional)
To enable packet trace and event trace click on the configure reports tab in the ribbon on the top as shown below. For detailed help about the packet and event trace, please refer to sections 8.4 and 8.5 in the User Manual.
Figure-16: Enable Packet Trace, Event Trace & Plots options on top ribbon.
Enable protocol specific logs and plots
NetSim provides protocol-specific logs for MANET libraries, which users can enable before running a simulation. These can be enabled by clicking on configure reports in top ribbon > clicking on plots > choosing as desired, and running the simulation
Figure-17: Enabling the Network logs in MANET
Similarly, users can enable the plots for Wi-Fi radio measurements and energy.
Figure-18: Enabling the Plots in MANET
GUI Configuration Parameters
Wireless Node Omni and Sector Ants Properties |
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|---|---|---|---|
Interface(Wireless)- Datalink Layer |
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Parameter |
Scope |
Range |
Description |
Rate Adaptation |
Global (Standard MANETs) Per MANET (Inter connected MANETs |
False |
The algorithm is similar to Receiver based Auto Rate (RBAR) algorithm. In this, the PHY rate gets set based on the target PEP (packet error probability) for a given packet size. The adaptation is termed as “FALSE” since the rate is pre-determined as per standard and there is no subsequent “adaptation”. |
Minstrel |
Rate adaptation algorithm implemented in Linux. |
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Generic |
The algorithm is similar to the Auto Rate Fallback (ARF) algorithm. In this algorithm (i) Rate goes up one step for 20 consecutive packet successes, and (ii) Rate goes down one step after 3 consecutive packet failures. |
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Short Retry Limit |
Local |
1 to 255 |
Determines the maximum number of transmission attempts of a frame. The length of MPDU is less than/ equal to Dot11 RTS Threshold value, made before a failure condition is indicated. |
Long Retry Limit |
Local |
1 to 255 |
Determines the maximum number of transmission attempts of a frame. The length of MPDU is greater than Dot11 RTS Threshold value, made before a failure condition is indicated. |
Dot11 RTS Threshold |
Local |
0 to 4692480 |
The size of packets (or A-MPDU if applicable) above which RTS/CTS (Request to Send / Clear to Send) mechanism gets triggered. |
MAC Address |
Fixed |
Auto Generated |
The MAC address is a unique value associated with a network adapter. This is also known as hardware address or physical address. This is a 12-digit hexadecimal number (48 bits in length). |
Physical Type |
Global |
DSSS |
Direct Sequence Spread Spectrum. The physical type of parameter is set to DSSS if the standard selected is IEEE802.11b. |
OFDM |
Orthogonal Frequency Division Multiplexing is utilized as a digital multi-carrier modulation method. The physical type of parameter is set to OFDM if the standard selected is IEEE802.11a, g and p. |
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HT |
Operates in frequency bands 2.4GHz or 5GHz band. The physical type parameter is set to HT if the standard selected is IEEE802.11n. |
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VHT |
The physical type parameter is set to VHT if the standard selected is IEEE802.11ac. |
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Medium Access Protocol |
Local |
DCF |
DCF is the process by which CSMA/CA is applied to Wi-Fi networks. DCF defines four components to ensure devices share the medium equally: Physical Carrier Sense, Virtual Carrier Sense, Random Back-off timers, and Interframe Spaces (IFS). DCF is used in non-QoS WLANs. |
EDCAF |
QoS was introduced in 802.11e and is achieved using enhanced distributed channel access functions (EDCAFs). EDCA provides differentiated priorities to transmitted traffic, using four different access categories (ACs). With EDCA, high-priority traffic has a higher chance of being sent than low-priority traffic: a station with high priority traffic waits a little less before it sends its packet, on average, than a station with low priority traffic. Access Categories under EDCAF are:
CWmax(Slots): This attribute specifies the value of the maximum size of the window that is used by an AP for a particular AC for generating a random number for the backoff. The value of dot11EDCATableCWmax attribute is such that it could always be expressed in the form of 2^X - 1, where X is an integer. The default value for this attribute is a CWmax. Range is 0 to 65535. AIFSN(Slot):This attribute specifies the number of slots, after a SIFS duration. The STA, for a particular AC, senses the medium is idle, before transmitting or executing a backoff. The default value for this attribute is 7. Range is 2 to 15. MAX TXOP \(\left( \mathbf{\mu S} \right)\mathbf{:\ }\)This attribute specifies the maximum number of microseconds of an EDCA TXOP for a given AC. The default value for this attribute is 0 for all PHYs. Range is 0 to 65535. With ref to 802.11 standard. MSDU Lifetime: This attribute specifies (in TU) the maximum duration an MSDU, for a given AC, would be retained by the MAC before it is discarded. Range is 0 to 4294967295 (TU). |
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OCBA Activated |
Local |
True or False |
This parameter determines the type of standard to be chosen for the OFDM physical type.
|
BSS Type |
Fixed |
Auto Generated |
The BSS type is fixed to Infrastructure mode. The wireless device can communicate - with each other or with a wired network |
Interface Wireless- Physical Layer |
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Protocol |
Fixed |
IEEE 802.11 |
Defines the MAC and PHY specifications like IEEE802.11a/b/g/n/ac/p for wireless connectivity for fixed, portable and moving stations within a local area. |
Connection Medium |
Fixed |
Auto Generated |
Defines how the devices are connected or linked to each other. |
Standard |
Global (Standard MANETs) Per MANET (Inter connected MANETs |
IEEE 802.11 a/b/g/n/ac/p |
Refers to a family of specifications developed by IEEE for WLAN technology. The IEEE standards supported in NetSim are IEEE 802.11 a, b, g, n, ac and p. 802.11a provides up to 54 Mbps in the 5GHz band. 802.11b provides 11 Mbps in the 2.4GHz bands. 802.11g provides 54 Mbps transmission over short distances in the 2.4 GHz band. 802.11n adds up MIMO. 802.11ac provides support for wider channels and beamforming capabilities. 802.11p provides support to Intelligent Transportation Systems. |
Transmission Type |
Fixed |
DSSS |
Direct Sequence Spread Spectrum (DSSS), A radio transmission technique that spreads a narrowband signal across a wider carrier frequency band. Each transmission is assigned a 10-bit pseudorandom binary code sequence, which comprises a series of ones and zeros in a seemingly random pattern known to both the transmitter and receiver. |
OFDM |
Orthogonal Frequency Division Multiplexing (OFDM), OFDM is a frequency-division multiplexing (FDM) scheme utilized as a digital multi-carrier modulation method. A large number of closely-spaced orthogonal sub-carriers are used to carry data. The data is divided into several parallel data streams or channels, one for each sub-carrier. Each sub-carrier is modulated with a conventional modulation scheme (such as Quadrature Amplitude Modulation or Phase Shift Keying) at a low symbol rate maintaining total data rates similar to conventional single-carrier modulation schemes in the same bandwidth. |
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HT |
High Throughput(HT), HT stands for High Throughput. The IEEE 802.11 HT STA operates in frequency bands 2.4 GHz/ 5 GHz band. |
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VHT |
Very High Throughput (VHT), VHT stands for Very High Throughput. The IEEE 802.11 VHT STA operates in frequency bands below 6 GHz excluding the 2.4 GHz band. Most VHT features, among other benefits, increase the maximum throughput achievable between two VHT STAs over that achievable using HT(High Throughput) features alone. |
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Transmit Power |
Local |
0 to 1000 |
Transmitted signal power. Note that the transmit power is not split among the antennas. This value is applied to each antenna in a multi-antenna transmitter. Unit is mW. |
CCA Mode |
Fixed |
Auto generated |
A mechanism to determine whether a medium is idle or not. It includes Carrier sensing and energy detection. |
Frequency Band |
Local |
2.4, 5, 5.9 (Depends on the standard chosen) |
The centre frequency of the band at which the device is operating. Unit is GHz. |
Bandwidth |
Local |
5,10, 20, 40, 60, 80, 160 (Depends on the standard chosen) |
Bandwidth is a range of frequencies occupied by radio communication signal to carry most of its energy. Unit is MHz |
Standard Channel |
Local |
Depends on the standard chosen |
The channel options defined in the standards. The options would also depend on the frequency band if the standard supports multiple bands. |
SIFS |
Fixed |
Auto Generated |
The time interval required by a wireless device in between receiving a frame and responding to the frame. Unit is microseconds. |
Slot Time |
Fixed |
Auto Generated |
Time is quantized as slots in Wi-Fi. Unit is microseconds. |
Guard Interval |
Local |
400 and 800 |
Guard Interval is intended to avoid signal loss from multipath effect. Unit is nanoseconds. |
MCS Selection |
Local |
Auto Rate Fallback, Fixed |
MCS selection in Wi-Fi impacts data rates and efficiency. Auto Rate Fallback adapts the MCS based on signal quality. Fixed MCS locks the MCS. Default Value: Auto Rate |
Data MCS |
Local |
802.11b: 0-3 802.11a/g/p: 0-7 802.11n: 0-7 802.11ac: 0-9 (MCS 9 not available for 20MHz in VHT) |
Allows selection of the MCS value for different Wi-Fi standards. Determines the modulation and coding scheme. Default Value: 0. |
Data PHY Rate (Mbps) |
Local |
Determined by selected Data MCS and Wi-Fi standard |
Shows the physical layer data rate based on the chosen modulation and coding scheme. (MCS) |
CW Min |
Fixed |
Auto generated |
The minimum size of the Contention Window in units of slot time. The CW min is used by the MAC to calculate the back off time for channel access during a carrier sense. |
CW Max |
Fixed |
Auto generated |
The maximum size of the Contention Window in units of slot time. The CW is doubled progressively when collisions occur. |
Error Model |
Local |
SINR-BER-By-Table, SINR-BER-By-Formula |
Specifies how the Bit Error Rate (BER) is calculated: BER is determined based on predefined tables mapping SINR to BER. BER is calculated using mathematical formulas that account for the modulation and coding schemes used, based on the SINR value. |
Antenna Height |
Local |
0 to 100m |
It is used in the pathloss calculation in the following models: Cost231 Hata Urban, Cost231 Hata SubUrban, Hata Urban, Hata SubUrban and Two Ray. This parameter has no effect when using any of the other pathloss models. Default:0.0 m. |
Antenna Gain |
Local |
0 to 1000 dB |
A relative measure of an antenna’s ability to direct or concentrate radio frequency energy in a particular direction or pattern. The measurement is typically measured in dBi (Decibels relative to an isotropic radiator). |
Antenna Type |
Fixed |
Omnidirectional or Sector antenna |
NetSim supports two types of Antenna, Omnidirectional and Sector Antennas. |
Wireless Node Sector Ant |
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Antenna Model |
Fixed |
Currently NetSim only supports 2D passive antenna per 3GPP TR 37.840 |
|
Orientation Angle |
Local |
0-360\({^\circ}\) |
NetSim implements a 2D parabolic sector antenna as per 3GPP TR 37.840. The boresight angle denotes the direction of maximum gain, or the highest radiated power. The angle is defined to start at 0 from the positive X-axis. If positive Y points downward, the angle increases on clockwise rotation from the positive X-axis. If positive Y points upward, the angle increases in an anti-clockwise direction from the positive X-axis. The units for the boresight angle are in degrees. |
Element Gain(dB) |
Local |
-50 to +50 |
This is the maximum directional gain of the radiation element (in dB). The default value is 8 dBi. |
Front to Back Ratio (dB) |
Local |
10-40 |
The ratio of power gain between the front and rear of a directional antenna. |
Beam Width \(\mathbf{({^\circ})}\) |
Local |
0-90\({^\circ}\) |
The 3 dB, or half power, beamwidth of the antenna is defined as the angular width of the radiation pattern, between points 3 dB down from maximum beam level (beam peak). |
Power model |
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Power Source |
Local |
Main Line or Battery |
MANETs communicate with each other using battery power. By default, the power model is set to Main Line, which represents a general-purpose alternating current (AC) electric power supply. The power model is user-configurable, with adjustable properties. |
Energy Harvesting |
Local |
On or Off |
Energy harvesting is the process of deriving energy from external sources (e.g., solar power, thermal energy, wind energy, and kinetic energy), capturing it, and storing it for use in small, wireless autonomous devices, such as those in wearable electronics and wireless sensor networks. NetSim supports an abstract energy harvesting model in which a specified amount of energy (calculated from the recharging current and specified voltage) is periodically added to the remaining energy of the node to replenish the battery. This feature can be turned on or off. |
Initial Energy |
Local |
0.001-1000 mAh |
A node has an initial value which is the level of energy the node has at the beginning of the simulation. |
Transmitting Current |
Local |
0-5000 mA |
In the Transmitting mode (Tx mode), the node consumes energy to transfer packets or data. The amount of energy consumed in this mode depends on the number of packets sent by the node, greater the number of packets, the more energy is consumed. |
Idle Mode Current |
Local |
0-500 mA |
In idle mode, a node doesn't transmit or receive data but still listens to the wireless medium for potential packets and new nodes. This consumes less energy than sending or receiving, as no active communication occurs. |
Voltage |
Local |
0-10 V |
Voltage is a measure of the energy carried by the charge. |
Receiving Current |
Local |
0-1000 mA |
In the Receiving mode (Rx mode), the nodes are actively listening to the incoming data, it consumes the energy as it receives the data from the sender. |
Recharging Current |
Local |
0-20 mA |
Recharging Current refers to the flow of electric charge supplied to a battery during the recharging process |
Network Layer |
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Routing Protocol |
Global |
DSR, AODV, ZRP and OLSR AODV (Ad hoc on Demand Distance Vector) is an on-demand routing protocol for wireless networks that uses traditional routing tables to store routing information. AODV uses timers at each node and expires the routing table entry after the route is not used for a certain time. DSR (Dynamic Source Routing) is a routing protocol for wireless mesh networks. It is similar to AODV, in that it forms a route on-demand when a transmitting computer requests one. However, it uses source routing instead of relying on the routing table at each intermediate device. ZRP (Zone Routing Protocol) is a hybrid Wireless Networking routing protocol that uses both proactive and reactive routing protocols when sending information over the network. ZRP divides the entire network into zones of variable size. Every node in the network has a zone associated to it. OLSR (Optimized Link State Routing Protocol) is a proactive link-state routing protocol, which uses hello and topology control (TC) messages to discover and then disseminate link state information throughout the mobile ad hoc network. |
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DSR Routing Protocol |
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ACK Type |
Global |
Link Layer ACK or Network Layer ACK |
The user can enable either Link Layer Ack (Layer 2 ACK) or Network Layer ACK (Layer 3 ACK). Link Layer ACK uses MAC layer acknowledgment for route maintenance, while Network Layer ACK uses DSR acknowledgment for route maintenance. For more details, refer to sections 3.2.1 and 3.2.2 of the MANET Technology Library. |
AODV Routing Protocol |
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Hello Message |
Global |
Enable/Disable |
Hello messages are periodic broadcasts used to maintain local connectivity and discover neighbors, ensuring that nodes are aware of each other's presence. Enabled: You will observe Hello packets being sent and received in the simulation. Disabled: Hello packets are not transmitted or received Without HELLO messages, AODV's route discovery (RREQ/RREP) remains the same. However, route maintenance shifts from proactive local link sensing (via HELLO) to reactive link break detection |
ZRP and OLSR Routing Protocol |
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Hello Interval |
Global |
1-100 s |
Hello interval parameter is used for neighbor discovery process. This parameter determines how frequently Hello messages are sent out and also how frequently a neighbor table will be updated. |
Refresh Interval |
Global |
1-100 s |
Refresh interval is the duration after which each active node periodically refreshes routes to itself. |
IARP |
Fixed |
IARP is used by a node to communicate with the interior nodes of its zone and is limited by the zone radius. |
|
TC Interval |
Global |
1-100 s |
Topology Control messages are the link state signaling done by OLSR. These messages are sent at TC interval every time. |
Zone radius |
Global |
2-225 m |
Zone radius parameter is present for ZRP Protocol. ZRP divides the entire network into zones. The radius of these zones is defined by Zone radius. |
Table-2: Datalink layer, Network layer and Physical layer properties for Wireless Node Omni and Sector Ants.
Run Simulation
Click on Run Simulation icon on the top toolbar
Figure-19: Run Simulation option on top ribbon
Set the Simulation Time and click on OK.
Figure-20: Run Simulation window
Note on MANET implementation in NetSim:
If a user wants to implement an HTTP application among nodes, TCP must be enabled in source node as TCP is set to disable by default.
OLSR is a proactive link-state routing protocol. It uses Hello and topology control (TC) messages to discover and then disseminate link state information throughout the mobile ad hoc network.
Individual nodes use this topology information to compute next hop destinations for all nodes in the network using shortest hop forwarding paths. For topology control (TC) messages to disseminate throughout, it requires 5 or more seconds depending upon the network size. In general, it is (5.5 secs + Tx Time * network size).
Hence, when simulating OLSR in MANET the Application Start Time must be greater than 5s (preferably greater than 10s) because in OLSR Topology Control (TC) messages start at 5s. Once the TC messages are sent, some further time will be required for OLSR to find the route. This can be done by setting the “Start Time” parameter in Application properties.