Internet of Things (IoT)

IoT/WSN White Papers

Overview

The Internet of Things (IoT) refers to a vast network of interconnected devices that communicate and exchange data via the internet or other networks. These devices, ranging from simple sensors to complex machines, can collect, process, and act on data, often autonomously. IoT technology enables enhanced interactivity and automation across various domains, from smart homes to industrial applications.

IoT in NetSim

NetSim provides a powerful platform for simulating IoT networks with the following characteristics:

  • Abstract Sensors: NetSim uses abstract sensors that can represent any type of sensor or embedded device.
  • Data Simulation: These sensors simulate the sensing of physical properties or random "fields" such as temperature or pressure.
  • Data Transmission: Sensed data is transmitted as IP packets with user-configurable size and inter-packet arrival time.
  • Network Focus: NetSim primarily simulates the transmission of these IP packets over an IoT network.

NetSim focuses on network behavior rather than the specific content of the data being transmitted. It does not process the actual "application payload" or perform data storage and analytics on this payload.

IOT-WSN Fig: A typical IoT scenario in NetSim. A large wireless sensor network can be created using the quick placement utility.

NetSim IoT /WSN stack

  • Application Layer: Sensor App as well as applications such as Voice, Video, CBR etc.
  • Transport Layer: UDP
  • Network layer: Muli-hop ad hoc routing protocols AODV and RPL
  • MAC and PHY layers: IEEE 802.15.4 Zigbee
  • Energy module: Models power usage during transmission, reception, and idle states, as well as energy harvesting capabilities

NetSim models IoT as a WSN that connects to an Internetwork through a 6LowPAN Gateway. The 6LowPAN Gateway uses two interfaces: a Zigbee (802.15.4) interface and a WAN Interface. The WSN sends data to a 6LowPAN Gateway. The Zigbee interface allows wireless connectivity to the WSN while the WAN interface connects to the external Internetwork.

IEEE 802.15.4 uses either Beacon Enabled or Disabled Mode for packet transmission. In Beacon Enabled Mode, nodes use slotted CSMA/CA algorithm for transmitting packets else they use Unslotted CSMA/CA.

IOT-WSN Fig: A typical application scenario that can be modeled in NetSim. Sensors can generate (measurement) packets that get queued in its packet buffer. These are then transmitted - directly or via hops - over a wireless link to a gateway that then forwards the packet via the internet to a server. Wireless links support various propagation models and ad hoc routing is supported for multi-hop communication. The MAC/PHY layer protocol supported is 802.15.4.

Network Performance Metrics and Log Files

IOT-WSN Fig: The Result dashboard and Plot window shown in NetSim after completion of simulation

NetSim Performance Measures and Integrations

Comprehensive Performance Metrics

NetSim provides a wide range of tabular and graphical performance measures, including:

  • End-to-end delays
  • Jitter
  • Errors
  • Packets (generated / received / collided)
  • Route tables
  • TCP Acks and retransmissions

Multi-level Result Organization

Results are organized at various levels:

  • Per interface
  • Per device
  • Per application
  • Per link
  • System-wide (network-level) summary metrics

In-Depth Analysis Tools

  • Trace Files: Contain individual packet flow and event execution information
  • Protocol Log Files: Record detailed protocol operation data for comprehensive analysis
  • Radio-Measurements File: Captures wireless metrics including pathloss, shadow fading loss, received power, SNR, Interference Power, SINR, and more

Data Export and Integrations

  • CSV Export: Results can be exported as .csv files for use in spreadsheet software like Excel
  • Wireshark Integration: pcap files can be recorded at each node for protocol analysis in Wireshark
  • MATLAB/Python Interface: NetSim can be interfaced with MATLAB/Python offline or online (run-time)

Useful Links