Duplicate Detectable Opportunistic Forwarding in Duty-Cycled Wireless Sensor Networks

Duplicate Detectable Opportunistic Forwarding in Duty-Cycled Wireless Sensor Networks

Duplicate Detectable Opportunistic Forwarding in Duty-Cycled Wireless Sensor Networks
Duplicate Detectable Opportunistic Forwarding in Duty-Cycled Wireless Sensor Networks


Opportunistic routing, offering relatively efficient and adaptive forwarding in low-duty-cycled sensor networks, generally allows multiple nodes to forward the same packet simultaneously, especially in networks with intensive traffic. Uncoordinated transmissions often incur a number of duplicate packets, which are further forwarded in the network, occupy the limited network resource, and hinder the packet delivery performance. Existing solutions to this issue, e.g., overhearing or coordination based approaches, either cannot scale up with the system size, or suffer high control overhead. We present Duplicate-Detectable Opportunistic Forwarding (DOF), a duplicate-free opportunistic forwarding protocol for low-duty-cycled wireless sensor networks. DOF enables senders to obtain the information of all potential forwarders via a slotted acknowledgment scheme, so the data packets can be sent to the deterministic next-hop forwarder. Based on light-weight coordination, DOF explores the opportunities as many as possible and removes duplicate packets from the forwarding process. We implement DOF and evaluate its performance on an indoor testbed with 20 TelosB nodes. The experimental results show that DOF reduces the average duplicate ratio by 90%, compared to state-of-the-art opportunistic protocols, and achieves 61.5% enhancement in network yield and 51.4% saving in energy consumption.


  • Most duplicate packets are generated when several for-warders keep awake and receive the same data packet during the same period. In low-duty-cycled sensor networks, the high traffic load will significantly increase the risk of producing duplicates.
  • Although several duplicate suppression mechanisms are proposed, the overhearing-based approaches are not well adapted to the bursty traffic, especially in the large-scale networks with dynamic links. Moreover, according to MORE, the long coordination process diminishes the benefits brought by opportunistic routing. The amount of duplicate packets might increase exponentially along the Multi hop relay such that the network throughput is significantly degraded.


  • Decrease System Performance
  • Decrease Network Throughput
  • Consumes more energy


  • We propose Duplicate-Detectable Opportunistic Forwarding (DOF) Instead of direct data transmission in LPL; a sender sends a probe and asks the potential forwarders to acknowledge the probe respectively in different time-slots. By utilizing the temporal diversity of multiple acknowledgments; the sender detects the quantity and differentiates the priority of all potential forwarders. The sender then forwards its data in the deterministic way to avoid multiple forwarders hearing the same packets.
  • We develop method store-solve possible collisions among multiple acknowledgments and exploit temporal long good links for opportunistic forwarding. With the lightweight mechanism to suppress duplicates, DOF can adapt to various traffic loads in duty-cycled sensor networks and enhances the system performance with respect to both net-work yield and energy efficiency.


  • Increase system/network performance
  • Increase network throughput
  • It consumes less energy




  • System : Pentium Dual Core.
  • Hard Disk : 120 GB.
  • Monitor : 15’’ LED
  • Input Devices : Keyboard, Mouse
  • Ram : 1 GB


  • Operating system : Windows XP/UBUNTU.
  • Implementation : NS2
  • NS2 Version : 2.28
  • Front End : OTCL (Object Oriented Tool Command  Language)
  • Tool : Cygwin (To simulate in Windows OS)


Daibo Liu, Mengshu Hou, Member, IEEE, Zhichao Cao, Member, IEEE, ACM, Jiliang Wang, Member, IEEE, Yuan He, Member, IEEE, and Yunhao Liu, Fellow, IEEE, “Duplicate Detectable Opportunistic Forwarding in Duty-Cycled Wireless Sensor Networks”, IEEE/ACM TRANSACTIONS ON NETWORKING, VOL. 24, NO. 2, APRIL 2016.