Featured Examples

Sample configuration files for all networks are available in Examples Menu in NetSim Home Screen. These files provide examples on how NetSim can be used – the parameters that can be changed and the typical effect it has on performance.

NOTE: In all VANET featured examples, the error model is set to SINR BER by Formula.

Importing a simple VANET scenario from SUMO¶

Open NetSim and Select Examples > VANETs > Importing a simple VANET scenario from SUMO then click on the tile in the middle panel to load the example as shown in below screenshot.

This scenario involves a simple road traffic network scenario as shown below:

An equivalent network is created in NetSim by importing the SUMO configuration file. In NetSim the TCP/IP stack parameters of the devices are configured along with network traffic between vehicles.

Network scenario after importing into NetSim and configuring application traffic

The properties of Application, vehicle and link are set as follows:

Application, Link and Physical layer Properties
Properties	Properties
Application Type	BSM
Application Method	UNICAST
Packet Size	20 (Bytes)
Inter Arrival Time	1000000 (\(\mu\)s)
Link Properties
Channel Characteristics	No Pathloss
Physical Layer Properties (Vehicle)
Standard	IEEE802.11p
Transmitter Power	40 mW
Antenna Gain	1 dBi
Antenna Height	1 m
Bandwidth	10 MHz

Note that the packet trace is enabled under the Configure Reports tab, and the mobility log is enabled under the Network Logs present in the plots on the right side. This allows for the recording of data traffic flow and vehicular movement.

After running the simulation, Packet Trace can be used to visualize packet flow along with packet information and Mobility log can be used to record vehicle mobility.

Simulation results dashboard provides the performance metrics of protocols running in different layers of the network stack of the devices.

V2V and V2I communication involving Vehicles and RSUs¶

Open NetSim and Select Examples > VANETs > V2V and V2I communication involving Vehicles and RSUs then click on the tile in the middle panel to load the example as shown in below screenshot.

NetSim VANETs module supports V2V and V2I communication. RSUs are now part of the GUI environment and can be dropped in addition to importing Vehicles from a SUMO configuration. Traffic can be configured between vehicles (V2V) and between vehicles and RSUs (V2I).

This scenario involves a simple road traffic network scenario as shown below:

An equivalent network is created in NetSim by importing the SUMO configuration file as shown below:

Network set up for scenario involving vehicles and RSUs for V2V and V2I communication

After importing the SUMO configuration file in NetSim, RSUs were added at junctions. In NetSim the TCP/IP stack parameters of the devices are configured along with network traffic between vehicles and between vehicles and RSUs.

Settings done for the Experiment:

Application, Link and Physical layer Properties
Properties	Properties
App Type	CBR
Application Method	BROADCAST
Transport Protocol	UDP
Packet Size	1460 (Bytes)
Inter Arrival Time	1000000 (\(\mu\)s)
Application-2 and 3 Properties
App Type	BSM
Application Method	UNICAST
Packet Size	20 (Bytes)
Inter Arrival Time	1000000 (\(\mu\)s)
Link Properties
Channel Characteristics	No Pathloss
Physical Layer Properties (Vehicles & RSU)
Standard	IEEE802.11p
Transmitter Power	40 mW
Antenna Gain	1 dBi
Antenna Height	1 m
Bandwidth	10 MHz

Note that the packet trace is enabled under the Configure Reports tab, and the mobility log is enabled under the Network Logs present in the plots on the right side. This allows for the recording of data traffic flow and vehicular movement.

After running the simulation, Packet Trace can be used to visualize packet flow along with packet information and mobility log can be used to record vehicle mobility.

Simulation results dashboard provides the performance metrics of protocols running in different layers of the network stack of the devices.

Throughput, delay and collisions with SCH and CCH time division¶

All the following examples are available in NetSim GUI. Navigate to Example > VANETs > Throughput, delay and collisions with SCH and CCH time division. Within Throughput, delay and collisions with SCH and CCH time division users will see four folders. Each folder comprises simulation samples for Parts 1, 2, 3 and 4 as explained below.

Background¶

Dedicated short range communication (DSRC) which uses two channels: Service channel SCH and Control channel (CCH). Each synchronization interval SI is split as follows:

We see the time divisions in DSRC. Each synchronization period consists of 1 CCH, 1 SCH and 1 guard interval. While the sync period is generally equal to 100 ms. NetSim allows users to modify the CCH and SCH interval, and in turn the total Sync period.

All devices switch between SCH and CCH and the alternation is based on the time divisions. NetSim allows the user to configure values of CCH interval, SCH interval and Guard interval. The default channels used in NetSim are SCH 171 (5.855 GHz) and CCH 178 (5.890 GHz).

Multiple nodes access the medium using 802.11p protocol. IEEE 802.11p PHY operates in the 5.9 GHz band with a channel bandwidth of 10 MHz. 802.11p is an adaptation of the IEEE 802.11a standard used in Wi-Fi systems.

Simulation scenario¶

Illustration of the VANET scenario under study. The network comprises 4 vehicles and 1 roadside unit. Each vehicle transmits two applications: (i) a BSM broadcast application that is sent to all other devices (vehicles plus RSU) within range and (ii) a CBR application transmitted to the RSU

The scenario comprises four vehicles, V1, V2, V3 and V4 communicating to the RSU, R1 and to one another. Each vehicle sends unicast CBR traffic to the RSU and broadcasts BSM (safety messages) to one another. Recall that per DSRC functioning, BSM is sent on the CCH while CBR is sent on the SCH.

Simulation parameters and results¶

Part 1: Throughput¶

Open NetSim and Select Examples > VANETs > Throughput, delay and collisions with SCH and CCH time division > Throughput then click on the tile in the middle panel to load the example as shown in below figure.

List of scenarios for the example of Throughput

The following network diagram illustrates what the NetSim UI displays when you open the example configuration file throughput as shown in below figure.

Network setup for studying the Throughput

Settings done for the Experiment:

Application, link and Physical layer Properties
Properties	Properties
Application Type	BSM (Applications 1–4)
Application Method	Broadcast
Packet Size	20 (Bytes)
Inter Arrival Time	320 (\(\mu\)s)
Application Type	CBR (Applications 5–8)
Application Method	Unicast
Packet Size	1460 (Bytes)
Inter Arrival Time	6147.4 (\(\mu\)s)
Link Properties
Channel Characteristics	Pathloss Only
Pathloss Model	Log distance
Pathloss Exponent	2
Datalink Properties
CCH Time	20 ms, 25 ms, 30 ms, 50 ms (Varying)
SCH Time	80 ms, 75 ms, 70 ms, 50 ms (Varying)
Physical Layer Properties (Vehicle)
Standard	IEEE802.11p
Transmitter Power	100 mW
Antenna Gain	1 dBi
Antenna Height	1 m
Bandwidth	10 MHz

Note that the packet trace is enabled under the Configure Reports tab, and the mobility log is enabled under the Network Logs present in the plots on the right side. This allows for the recording of data traffic flow and vehicular movement.

Results

The BSM application is configured with packet size of 20B and inter-packet arrival time of 320 \(\mu s\), while the CBR application is configured with packet size of 1460B and inter-packet arrival time of 5840 \(\mu s\).

We see that as the CCH interval increases, BSM application has higher throughput rate. Similarly, as the SCH Interval decreases there is a decrease in throughput rate.
App	App Type	Gen. Rate (Mbps)	CCH 20ms SCH 80ms	CCH 25ms SCH 75ms	CCH 30ms SCH 70ms	CCH 50ms SCH 50ms
			Throughput (Mbps)
BSM 1	Broadcast	0.5	0.096	0.122	0.144	0.241
BSM 2	Broadcast	0.5	0.103	0.129	0.156	0.261
BSM 3	Broadcast	0.5	0.109	0.135	0.163	0.274
BSM 4	Broadcast	0.5	0.113	0.141	0.171	0.285
Sum Throughput (Mbps)			0.421	0.527	0.634	1.061
Sum Throughput \(\times\) (SCH+CCH)/CCH			2.106	2.107	2.114	2.123
CBR 1	Unicast	1.9	1.826	1.726	1.544	1.139
CBR 2	Unicast	1.9	1.778	1.691	1.604	1.190
CBR 3	Unicast	1.9	1.837	1.668	1.622	1.119
CBR 4	Unicast	1.9	1.884	1.762	1.619	1.087
Sum Throughput (Mbps)			7.328	6.849	6.391	4.537
Sum Throughput \(\times\) (SCH+CCH)/SCH			9.160	9.132	9.130	9.075

Observations

BSM is sent on CCH; CBR is sent on SCH. Increasing the fraction of time for CCH increases BSM throughput. Increasing the fraction of time for SCH increases CBR throughput.
As expected, Sum throughput divided by SCH fraction is equal for all cases. Similarly, Sum throughput divided by CCH fraction is equal in all cases. This verifies the working of time division between CCH and SCH.

Part 2: Delay¶

Open NetSim and Select Examples > VANETs > Throughput, delay and collisions with SCH and CCH time division > Delay then click on the tile in the middle panel to load the example as shown in below screenshot.

List of scenarios for the example of Delay

The following network diagram illustrates what the NetSim UI displays when you open the example configuration file as shown in below figure.

Settings done for the Experiment:

Application, Link and Physical layer Properties
Properties	Properties
Application Type	BSM (Applications 1–4)
Application Method	BROADCAST
Transport Protocol	WSMP
Packet Size	20 (Bytes)
Inter Arrival Time	6400 (\(\mu\)s)
Application Type	CBR (Applications 5–8)
Application Method	UNICAST
Transport Protocol	UDP
Packet Size	1460 (Bytes)
Inter Arrival Time	11680 (\(\mu\)s)
Link Properties
Channel Characteristics	Pathloss Only
Pathloss Model	Log Distance
Pathloss Exponent	2.5
Data Link Properties
CCH Time	20 ms, 25 ms, 30 ms, 50 ms (Varying)
SCH Time	80 ms, 75 ms, 70 ms, 50 ms (Varying)
Physical Layer Properties (Vehicle)
Standard	IEEE802.11p
Transmitter Power	100 mW
Antenna Gain	1 dBi
Antenna Height	1 m
Bandwidth	10 MHz

Note that the packet trace is enabled under the Configure Reports tab, and the mobility log is enabled under the Network Logs present in the plots on the right side. This allows for the recording of data traffic flow and vehicular movement.

Results

When analyzing delay, we change the generation rate such that it is below the saturation capacity of the network. If this were not so, then queuing delay would blow-up at (and post) saturation.

We see that as the CCH interval increases, the delay for BSM application decreases. Similarly, as the SCH interval decreases the delay for CBR application increases.
App	App Type	Gen. Rate (Mbps)	CCH 20ms SCH 80ms	CCH 25ms SCH 75ms	CCH 30ms SCH 70ms	CCH 50ms SCH 50ms
			Delay (Micro sec)
BSM 1	Broadcast	0.025	38298.82002	33567.59002	29364.14199	15288.49474
BSM 2	Broadcast	0.025	41113.5348	34376.05357	29509.69213	15465.28051
BSM 3	Broadcast	0.025	43021.08925	34569.64036	29879.04223	15326.54219
BSM 4	Broadcast	0.025	38675.9637	34123.20029	30135.26103	15669.02365
Average Delay			40277.35	34159.12	29722.03	15437.33
CBR 1	Unicast	1	9911877.311	10231477.86	46601863.3	46930314.68
CBR 2	Unicast	1	24811785.51	26206924.26	31849109.01	11474867.33
CBR 3	Unicast	1	4244775.494	4518140.717	10246485.37	35513878.28
CBR 4	Unicast	1	47748603.46	48624907.15	3994697.125	4828944.515
Average Delay			21679260.45	22395362.5	23173038.7	24687001.2

Observations

CCH Delay has 3 components (a) waiting time where the packet is waiting for the SCH to complete (b) Medium access time and (c) Transmission time.
The mathematical analysis of delay is complex. It involves evaluating two difficult components (i) CCH packet waiting time while SCH packet is served and vice versa, and (ii) medium access time. We leave the mathematical analysis to interested researchers, and restrict ourselves to stating that the trends are as expected i.e., increasing CCH time (and reducing SCH time) reduces the CCH delay (and increases SCH delay).

Part 3: Collision count with increasing generation rate¶

Open NetSim and Select Examples > VANETs > Throughput, delay and collisions with SCH and CCH time division > Collision count with increasing generation rate then click on the tile in the middle panel to load the example as shown in below screenshot.

List of scenarios for the example of Collision count with increasing generation rate

The following network diagram illustrates what the NetSim UI displays when you open the example configuration file as shown in below figure.

Network setup for studying the Collision count with increasing generation rate

The scenario layout remains the same, however we change the application settings. In this example we only have 4 BSM applications. There are no CBR applications.

Settings done for the Experiment:

Application, link and Physical layer Properties
Properties	Properties
App Type	BSM
Application Method	Broadcast
Packet Size	20 (Bytes)
Inter Arrival Time	32000 (\(\mu\)s), 16000 (\(\mu\)s), 10666.67 (\(\mu\)s), 8000 (\(\mu\)s) (Varying)
Link Properties
Channel Characteristics	No pathloss
Datalink Properties
CCH Time	20 ms
SCH Time	80 ms
Physical Layer Properties (Vehicle)
Standard	IEEE802.11p
Transmitter Power	100 mW
Antenna Gain	1 dBi
Antenna Height	1 m
Bandwidth	10 MHz

Note that the packet trace is enabled under the Configure Reports tab, and the mobility log is enabled under the Network Logs present in the plots on the right side. This allows for the recording of data traffic flow and vehicular movement.

Results

The application generation rates are mentioned in Row 1 (shaded grey).

Comparison of Collision count of BSM applications with changing generation rate
App	App Type	Gen Rate 0.005 Mbps	Gen Rate 0.010 Mbps	Gen Rate 0.015 Mbps	Gen Rate 0.020 Mbps
		Collision Count	Collision Count	Collision Count	Collision Count
BSM 1	Broadcast	168	468	793	1244
BSM 2	Broadcast	157	453	810	1144
BSM 3	Broadcast	151	365	688	926
BSM 4	Broadcast	44	121	214	301
Total collisions		520	1407	2505	3615
Total pkts transmitted		29932	59820	89724	119584
Collision Probability		0.017	0.024	0.028	0.030

The Collision probability is the ratio between Collision count to total number of packets transmitted:

\[\text{Collision probability} = \frac{\text{Collision count}}{\text{packets transmitted}}\]

To find the Collision count of each individual application:

Click on Packet trace under traces present in the results dashboard window (Please make sure the packet trace is enabled before running the simulation)

Total no of collision counts, and packets transmitted can be viewed in the link metrics table over results dashboard.
In packet trace, filter the control packet type / App Name to App1_BSM to find the individual collision count.
Along with that filter the packet status field to collisions to view the collisions of that application (APP1 BSM).

Packet trace which depicts filtering of applications

Packet trace that depicts filtering of packet status of each application

After applying the filters, the total collision count of APP1 BSM applications can be viewed.

Same process can be done for all the remaining applications of the network.

Observations

Saturation throughput is about 0.25 Mbps per app or 1 Mbps total. Note the generation rate is below the saturation capacity of the network.
We see collision probability increases as generation rate increases.
To the best of our knowledge the mathematical modelling of collisions with non-saturated queues is an open problem. The Bianchi model exists for predicting collision counts with saturated queues, subject to certain conditions.

Part 4: Collisions count with increasing number of nodes¶

Open NetSim and Select Examples > VANETs > Throughput, delay and collisions with SCH and CCH time division > Collisions count with increasing number of nodes then click on the tile in the middle panel to load the example as shown in below screenshot.

List of scenarios for the example of Collisions count with increasing number of nodes

The following network diagram illustrates what the NetSim UI displays when you open the example configuration file as shown in below figure.

Network set up for studying the Collisions count with increasing number of nodes

This scenario has 10 vehicles in a line on a road. The vehicles transmit power \(P_t = 20\) dBm, Carrier sense threshold \(CS_{th} = -85\) dBm, and we assumed log distance pathloss with \(\eta = 2.5\). The received power between nodes with maximum separation, \(d = 100\), is:

\[P_r = 20 - 47.88 - 10 \times 2.5 \times \log(100) = -77.88 \text{ dBm}\]

Based on the formula:

\[Rx_{\text{Power}} = Tx_{\text{Power}} + G_t + G_R - PL_{d0} - 10 \log(D^{\eta})\]

For detailed understanding of the receive power calculations refer to Propagation model:

https://tetcos.com/downloads/v14.1/Propagation-Models.pdf

Since \(P_r > CS_{th}\) all nodes can hear one another which means that they are all within CS Range.

Illustration of the VANET scenario under study. The network comprises of 10 vehicles and 1 roadside unit. Each vehicle transmits one application (i) a BSM broadcast application that is sent to all other devices (vehicles plus RSU) within range. In this study we are increasing the Tx nodes from 1–10

Settings done for the Experiment:

Application, Link and Physical layer Properties
Properties	Properties
App Type	BSM
Application Method	BROADCAST
Packet Size	20 (Bytes)
Inter Arrival Time	320 (\(\mu\)s)
Link Properties
Channel Characteristics	No Pathloss
Data Link Properties
CCH Time	20 ms
SCH Time	80 ms
Physical Layer Properties (Vehicle)
Standard	IEEE802.11p
Transmitter Power	100 mW
Antenna Gain	1 dBi
Antenna Height	1 m
Bandwidth	10 MHz

Note that the packet trace is enabled under the Configure Reports tab, and the mobility log is enabled under the Network Logs present in the plots on the right side. This allows for the recording of data traffic flow and vehicular movement.

Results

Collision probability comparison with change in number of transmitting nodes
Number of Tx nodes	Collision Count	Pkts transmitted	Collision Probability
	0	31261	0.000
2	0	75726	0.000
3	1731	127041	0.014
4	7142	187016	0.038
5	16724	252210	0.066
6	32045	325308	0.099
7	53946	405678	0.133
8	86203	499376	0.173
9	126970	596448	0.213
10	176435	704510	0.250

The total number of collision counts and packets transmitted can be viewed in link metrics window of results dashboard.

Collision probability vs. number of transmitting nodes

The Collision probability is the ratio between Collision count to total number of packets transmitted:

\[\text{Collision probability} = \frac{\text{Collision count}}{\text{packets transmitted}}\]

Observations

We see collision count increasing with number of transmitting nodes.
This can be compared against the Bianchi analytical model.

SUMO Manhattan Mobility with Single and Multi-hop Communication¶

Introduction

The Manhattan mobility in SUMO features a grid topology as shown below. It is composed of a number of horizontal and vertical streets. Each street has two lanes for each direction (North and South direction for vertical streets, East and West for horizontal streets). The mobile node is allowed to move along the grid of horizontal and vertical streets. At an intersection of a horizontal and a vertical street, the mobile node can turn left, right or go straight with certain probability.

Case 1: Manhattan mobility Single-hop RSU to vehicles

Objective

To create, using SUMO, a Manhattan Road network in which vehicles drive randomly, and to have a Roadside unit (RSU) which sends safety messages continuously to vehicles. The network performance is analyzed for different environments each having different RF channel characteristics.

Procedure

Open NetSim and Select Examples > VANETs > SUMO Manhattan mobility > Single hop communication then click on the tile in the middle panel to load the example as shown in below screenshot.

List of scenarios for the example of Single hop communication

The NetSim UI would display as shown below.

Network setup for studying the Single hop communication

Settings done for this sample experiment.

Configure CBR Applications (Broadcast application) set as below properties:

CBR Applications Settings
App Method	App Type	App Name	Source ID	Destination ID	Pkt Size (B)	IAT (\(\mu\)s)
Broadcast	CBR	APP 1 CBR Broadcast	21	Broadcast to all 20 vehicles	300	2,000,000

Transport protocol set as UDP in application Configuring window.
Click on ad hoc link/wireless link, expand the right-side property panel and set the properties as follows:

Wireless link properties
Channel characteristics	Pathloss Model	Pathloss Exponent
Pathloss Only	Log distance	2.5

Co-ordinates of RSU are set as X = 428.61, and Y = 108.06.
Set transmitter power to 1000mW under Interface 1(wireless) > Physical layer properties of vehicles and RSU.
The packet trace is enabled under configure reports tab and the mobility log is enabled under the network logs present in the plots on the right side, allowing the recording of data traffic flow and the vehicular movement.
Increase the pathloss exponent (in the order 2.5, 3, 3.5, 4) and note down the aggregate throughput and packets received for different application generation rates.
After running the simulation, Packet Trace can be used to visualize packet flow along with packet information and Mobility log can be used to record vehicle mobility. Time varying throughput plot can be opened from the Results window.

In SUMO GUI, you can see that vehicles choose random directions when they reach a junction in the Manhattan grid network.

Results and Observations

For sample RSU Broadcast Data Rate = 1.2 Kbps (Packet size = 300 bytes, IAT = 2,000,000\(\mu\)s. This means packets of size 300 Bytes are sent every 2 seconds).

Results Comparison for RSU Broadcast Data Rate = 1.2 Kbps
Environment	Path-loss Exponent	Packets Received (Aggregate)	Throughput (Kbps) (Aggregate)
Open Rural Area	2.5	980	23.52
Urban Area	3	511	12.264
Dense Urban Area	3.5	209	5.016
Very Dense Urban Area with Shadowing	4	57	1.368

* Aggregate is the sum of the packet/throughputs obtained by all applications.

For sample RSU Broadcast Data Rate = 2.4 Kbps (Packet size = 300 Bytes, IAT = 1,000,000\(\mu\)s or 1 second. This means packets of size 300 Bytes are sent every second).

Results Comparison for RSU Broadcast Data Rate = 2.4 Kbps
Environment	Path-loss Exponent	Packets Received (Aggregate)	Throughput (Kbps) (Aggregate)
Open Rural Area	2.5	1960	47.04
Urban Area	3	1022	24.528
Dense Urban Area	3.5	413	9.912
Very Dense Urban Area with Shadowing	4	114	2.736

For sample RSU Broadcast Data Rate = 9.6 Kbps (Packet size = 300 Bytes, IAT = 250,000\(\mu\)s or 0.25 seconds. This means four packets of size 300 Bytes are sent every 0.25 second).

Results Comparison for RSU Broadcast Data Rate = 9.6 Kbps
Environment	Path-loss Exponent	Packets Received (Aggregate)	Throughput (Kbps) (Aggregate)
Open Rural Area	2.5	7920	190.08
Urban Area	3	4107	98.568
Dense Urban Area	3.5	1659	39.816
Very Dense Urban Area with Shadowing	4	461	11.064

Plot of Throughput vs. Pathloss Exponent for different RSU broadcast for different DR (Data Rates)

Case 2: Manhattan mobility Multi-hop Vehicles to RSU

Objective

To create, using SUMO, a Manhattan Road network in which vehicles drive randomly, and to have a Roadside unit (RSU) to which vehicles continuously send unicast traffic via multi-hop (hopping via other vehicles if the RSU is beyond communication range). The network performance is analyzed for different vehicle counts.

Procedure

Open NetSim and Select Examples > VANETs > SUMO Manhattan mobility > Multi hop communication then click on the tile in the middle panel to load the example.

List of scenarios for the example of Multi hop communication.

The NetSim UI would display as shown below.

Network set up for studying the Multi hop communication

Settings done for this sample experiment.

Configure CBR Application between the nodes as shown in the table and, click on application, expand the right-side property panel and set the application properties below.

CBR Applications settings
App Method	App Type	Source Id	Destination Id	Pkt Size (B)	IAT (\(\mu\)s)
Unicast	CBR	(All vehicles)	RSU	1460	20,000

In Vehicle General Properties, under SUMO file Configuration.sumo.cfg file was selected from the Docs folder of NetSim Install Directory <C:\Program Files\NetSim Standard\Docs\Sample-Configuration\VANET\SUMO-Manhattan-mobility-Single-hop-and-Multi-hop\Multi-hop-communication>

Transport protocol set as UDP in application Configuration window.
Click on Adhoc link / Wireless link and expand the right-side property panel and set Pathloss as No Pathloss.
RSU is dropped randomly as it is No Pathloss.
Click on the Vehicles and RSU and expand the right-side property panel and set Network layer routing protocol as DSR.
Set transmitter power to 1000mW under Interface 1(wireless) > Physical layer properties of Vehicles and RSU.
Mobility log is enabled under the network logs present in the plots on the right side, allowing the vehicular movement.
Run the simulation.
Increase the number of vehicles in the order 10, 20, 30 etc. and note down the aggregate throughput.

Result:

Results Comparison
Number of vehicles	Throughput (Kbps) (Aggregate)*
	1794.747
20	1575.164
30	1675.729
40	2579.062
50	1923.464

*Aggregate is the sum of the packet/throughputs obtained by all applications.

Aggregate Throughput vs. Number of Vehicles

SUMO Interfacing with vehicles moving in a closed loop¶

Open NetSim and Select Examples > VANETs > SUMO Vehicles in closed loop then click on the tile in the middle panel to load the example as shown in below figure.

List of scenarios for the example of SUMO Vehicles in closed loop

The NetSim UI would display as shown below.

Network set up for studying the SUMO Vehicles in closed loop

Settings done for this sample experiment:

Configure BSM (Basic Safety Message) Application between the nodes as shown in the table and, click on application, expand the right-side property panel and set the application properties below.

BSM Applications settings
APP_ID	Source ID	Destination ID	Packet Size (Bytes)	Inter-Arrival Time (\(\mu\)s)
APP_1_BSM	1	6 (RSU)	20	20,000
APP_2_BSM	2	6 (RSU)	20	20,000
APP_3_BSM	3	6 (RSU)	20	20,000

Transport protocol set as WSMP for all applications in application window.
In Vehicle Position properties, under SUMO file Configuration.sumo.cfg file was selected from the Docs folder of NetSim Install Directory <C:\Program Files\NetSim Standard\Docs\Sample-Configuration\VANET\SUMO-Vehicles-moving-in-closed-loop>

Click on Adhoc link/Wireless link and expand the right-side property panel and set Pathloss as No pathloss.
RSU is dropped randomly as it is set to No pathloss.
Click on vehicles and RSU, then expand the right-side property panel. Go to Interface(wireless) > Datalink layer Properties and set DCF as the Medium Access Protocol.
Set transmitter power to 1000mW under Interface 1(wireless) > physical layer properties of vehicles and RSU.
Note that the packet trace is enabled under the Configure reports tab, and the mobility log is enabled under the Network Logs present in the plots on the right side. This allows for the recording of data traffic flow and vehicular movement and run simulation.
After running the simulation, Packet trace can be used to visualize packet flow along with packet information and mobility log can be used to record vehicle mobility. Time varying throughput plot can be opened from the Results window.

Result:

Same can be observed in SUMO as well:

According to SUMO, the road network consists of ‘Edges’ and ‘Junctions’. The re-router (a device in SUMO and is not to be confused with Routers available in NetSim) established in the edge will re-route the vehicle from one edge to another after one successful revolution through the road network. The presence of a single re-router will forward the vehicles from one edge to other and then the vehicle eventually stops its movement. Hence, two re-routers have been established in two edges which re-route the vehicle from one edge to other. The above road network consists of six edges in which re-routers are established in the starting and ending edges, which re-routes the vehicles present in the network from starting edge to the finishing edge after one complete revolution through the road or path. As a result, the vehicles will move through the closed loop continuously, until the end time configured in the configuration file.

The RSU configured in the network will allow V2I communication. Per the application configuration a 100 bytes packet is transmitted from vehicle to RSU every 2 seconds. This can also be observed in the packet trace.