Simulation GUI
Create Scenario
Open NetSim and click New Simulation 🡪 Vehicular Adhoc Network (Vanet) as shown in Figure-1
Figure-1: NetSim Home Screen
A dialogue box appears as shown below, in that browse the Sumo Configuration File path. The general format of such file is “*.Sumo.cfg”.
Figure-2: Sumo Configuration File path
The NetSim VANET module is designed to interface directly with SUMO.
A SUMO configuration file is required as an input to NetSim.
Sample SUMO configuration files are available inside the Config support folder, which is present in each example in the <NetSim-Installation-Directory>\Docs\Sample Configuration\VANET folder.
Users can either use a Sumo configuration file which is provided inside NetSim’s installation directory or use a different user specified SUMO configuration file. This .cfg file contains the path of NETWORK file and VEHICLES file.
Further help on how to create SUMO configuration files is available at http://sumo.dlr.de/wiki/Networks/Building_Networks_from_own_XML-descriptions.
After selecting the SUMO configuration file, the scenario opens with nodes placed at their respective starting positions (tracked from SUMO). Roads and traffic lights are also placed exactly as specified in the SUMO configuration file.
Devices specific to NetSim VANETs Library
Vehicle (with one OBU): In NetSim, a vehicle is a mobile communications device. It is assumed to have one (1) on board unit (OBU) which is a 5-layer device. The OBU can communicate with other OBUs or with RSUs via an Ad hoc link. The OBU is assumed to have one wireless interface and has its own IP and MAC addresses.
Roadside Unit (RSU): In NetSim, an RSU is a fixed communicating device. RSUs are generally termed as infrastructure. Vehicle (OBU) to RSU is termed as V2I communication. The RSU is a 5-layer device that can be connected to a Vehicle or to a Router. RSUs cannot be directly connected to other RSUs. RSUs have one (1) wireless interface and one (1) serial interface, and each interface has its own IP and MAC addresses.
Wired node: A Wired node can be an end-node or for a server. It is a 5-layer device that can be connected to a switch and router. It supports only 1 Ethernet interface and has its own IP and MAC Addresses.
Wireless Nodes: A Wireless node can be an end-node or a server. It is a 5-layer wireless device that can be connected to an Access point. It supports only 1 Wireless interface and has its own IP and MAC Addresses.
L2 Switch: A Switch is a layer-2 device that uses the devices’ MAC address to make forwarding decisions. It does not have an IP address.
Router: Router is a layer-3 device and supports a maximum of 24 interfaces each of which has its own IP address.
Access point: Access point (AP) is a layer-2 wireless device working per 802.11 Wi-Fi protocol. It can be connected to wireless nodes via wireless links and to a router or a switch via a wired link.
Figure-3: VANET Library Device Palette in GUI
Set Node, Link and Application Properties
Right click on the appropriate node or link and select Properties. Then modify the parameters according to the requirements.
Routing Protocol in Network Layer and all user editable properties in Data Link Layer few properties are Global or Local, Physical Layer and Power are Local.
Physical layer standards are acting as Link global.
In the General properties, Mobility model is set to SUMO, and it is editable. This signifies that the Node movements will be traced from SUMO.
File name gives the path to Sumo Configuration file that was given by the user.
Step Size is taken from the Sumo Configuration file specified which tells the amount of time paused in sumo corresponding to a single step of SUMO Simulation.
In Interface (wireless) properties, under Physical layer, by default Standard is set to IEEE 802.11p in case of VANET.
The following are the important properties of VANET Wireless Node (RSU/Vehicle) in Data link and Physical layers.
Figure-4: Vanet > Datalink layer properties window
Figure-5: Vanet > Physical layer properties window
Figure-6: Vanet > Physical layer properties window > Battery model
Click on the Application icon present in the Set Traffic option and set properties. Multiple applications can be generated by using add button in Application properties.
Figure-7: Application icon present on top ribbon
Set the values according to requirement and click OK.
Figure-8: Application Configuration window
Detailed information on Application properties is available in Section 6 of NetSim User Manual.
Enable Packet Trace, Event Trace & Plots (Optional)
For detailed packet information, enable packet and event tracing before running the simulation. To enable trace files, click on Configure Reports in the top ribbon, check the Packet Trace and Event Trace checkboxes. For further analysis, please refer to Sections 8.4 and 8.5 in User Manual.
Figure-9: Enable Packet Trace, Event Trace & Plots options on top ribbon.
Enable protocol specific logs and plots
NetSim provides protocol-specific logs for VANET 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-10:Enabling IEEE 802.11 Radio measurements log in VANETs
Similarly, users can enable the plots for Wi-Fi radio measurements and energy.
Figure-11: Enabling plots for VANETs
GUI Configuration Parameters
Vehicle |
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|---|---|---|---|
Interface(Wireless)- Datalink Layer |
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Parameter |
Scope |
Range |
Description |
CCH Time (\(\mathbf{\mu s)}\) |
Global |
0-1000000 |
A radio channel, intended for the exchange of management information. In NetSim when a BSM (safety) application is configured, it is transmitted on the CCH. |
SCH Time (\(\mathbf{\mu s)}\) |
Global |
0-1000000 |
A radio channel used for non-safety applications. In NetSim, when non safety applications such as CBR, Voice, Video, FTP etc., are configured, they are transmitted on the CCH. |
Guard interval (\(\mathbf{\mu s)}\) |
Global |
1-100 |
A time interval at the start of each control channel (CCH) interval and service channel (SCH) interval during which devices that are switching channels do not transmit. |
Rate Adaption |
Cell |
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. |
||
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. |
||
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. |
||
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. |
||
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 |
IEEE802.11 |
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 |
Cell |
IEEE802.11 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 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 |
The transmission type parameter is DSSS if the standard selected is IEEE802.11b. |
OFDM |
The transmission type parameter is OFDM if the standard selected is IEEE802.11a, g and p. |
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HT |
The transmission type parameter is HT if the standard selected is IEEE802.11n. |
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VHT |
The transmission type parameter is VHT if the standard selected is IEEE802.11ac. |
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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 |
Cell |
2.4, 5, 5.9 (Depends on the standard chosen) |
Range of frequencies at which the device operates. The frequency band depends on the standard selected. Unit is GHz. |
Bandwidth |
Cell |
5,10, 20, 40, 60, 80, 160 (Depends on the standard chosen) |
The bandwidth depends on the standard and the frequency band selected. 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. |
Standard Channel SCH |
Local |
SCHs are dedicated communication channels used for transmitting data and information between vehicles and RSUs in a VANET. The Standard Service Channels (SCHs) in VANETs are primarily used for general data exchange, including applications such as traffic information sharing, multimedia data transmission, and other non-safety-critical communications. Supported Channels: These are the specific channels designated for data transmission in the VANET. The list includes channels like SCH 172 (5860 MHz), SCH 174 (5870 MHz), SCH 176(5880 MHz), 180(5900MHz), 182(5910MHz) and 184 (5920 MHz). |
|
Standard channel CCH |
Local |
CCH 178 (5890 MHz) |
The Control Channel (CCH) serves as a specialized communication channel dedicated to the management and control of VANET operations. CCH is primarily used for disseminating safety-related information and network management messages. It plays a crucial role in supporting applications like collision avoidance and traffic management. The Control Channel in VANET operates at channel CCH 178 (5890 MHz). |
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 |
NetSim Vanet’s supports one type of Antenna, Omnidirectional Antenna. |
|
Power Source |
Local |
Main Line or Battery |
VANETs 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 |
|||
Routing Protocol |
Global |
DSR, AODV, ZRP and OLSR |
|
DSR Routing Protocol |
|||
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 |
|||
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 |
|||
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-1: Datalink layer, Network layer and Physical layer properties for Vehicles and RSUs
Run Simulation
Click on Run Simulation icon on the top toolbar. Simulation time is set from the Configuration file of Sumo. The simulation has three options.
Figure-12: Run Simulation option on top ribbon
SUMO determines the positions of vehicles with respect to time as per the road conditions. NetSim reads the coordinates of vehicles from SUMO (through pipe) during runtime and uses it as input for vehicle mobility.
Figure-13: NetSim simulation window and SUMO simulation window runs simultaneously
Users can see the movement of vehicles and observe vehicular simulation in SUMO and observe equivalent simulation in NetSim.