TTACCA: TWO-HOP BASED TRAFFIC AWARE CONGESTION CONTROL ALGORITHM FOR WIRELESS SENSOR NETWORKS

Congestion in Wireless Sensor Networks has negative impact on the Quality of Service. Congestion effects the performance metrics, namely throughput and per-packet energy consumption, network lifetime and packet delivery ratio. Reducing congestion allows better utilization of the network resources and thus enhances the Quality of Service metrics of the network. Traffic Aware Dynamic Routing to Alleviate Congestion in Wireless Sensor Networks reduces congestion by considering one hop neighbor routing in the network. This paper proposed an algorithm for Quality of Service Based Traffic-Aware Data forwarding for congestion control in wireless sensor networks based on two hop neighbor information. On detection of congestion, the algorithm forwards data packets around the congestion areas by spreading the excessive packets through multiple paths. The path with light load or under loaded nodes is efficiently utilized whenever congestion occurs. The main aspect of the algorithm is to build path to the destination using two independent potential fields depth and queue length. Queue length field solves the traffic-aware problem. Depth field creates a backbone to forward packets to the sink. Both fields are combined to yield a hybrid potential field to make dynamic decision for data forwarding. Network Simulator used for simulating the algorithm is NS2. The proposed algorithm performs better

A Priority Rate-Based Routing Protocol for wireless multimedia sensor networks

The development of affordable hardware has made it possible to transmit multimedia data over a wireless medium using sensor devices. Deployed sensors span larger geographical areas, generating different kinds of traffic that need to be communicated either in real-time or non-real-time mode to the sink. The tiny sized design of sensor nodes has made them even more attractive in various environments as they can be left unattended for longer periods. Since sensor nodes are equipped with limited resources, newer energy-efficient protocols and architectures are required in order to meet requirements within their limited capabilities when dealing with multimedia data. This is because multimedia applications are characterized by strict quality of service requirements that distinctively differentiate them from other data types during transmission. However, the large volume of data produced by the sensor nodes can easily cause traffic congestion making it difficult to meet these requirements. Congestion has negative impacts on the data transmitted as well as the sensor network at large. Failure to control congestion will affect the quality of multimedia data received at the sink and further shorten the system lifetime. Next generation wireless sensor networks are predicted to deploy a different model where service is allocated to multimedia while bearing congestion in mind. Applying traditional wireless sensor routing algorithms to wireless multimedia sensor networks may lead to high delay and poor visual quality for multimedia applications. In this research, a Priority Rate-Based Routing Protocol (PRRP) that assigns priorities to traffic depending on their service requirements is proposed. PRRP detects congestion by using adaptive random early detection (A-RED) and a priority rate-based adjustment technique to control congestion. We study the performance of our proposed multi-path routing algorithm for real-time traffic when mixed with three non real-time traffic each with a different priority: high, medium or low. Simulation results show that the proposed algorithm performs better when compared to two existing algorithms, PCCP and PBRC-SD, in terms of queueing delay, packet loss and throughput

Differentiated services based congestion control algorithm for Wireless Multimedia Sensor Networks

In this paper, a differentiated services based congestion control algorithm for Wireless Multimedia Sensor Networks (WMSNs) is proposed. Keeping in mind the characteristics of Wireless Sensor Networks (WSNs) and their possible extensions, the proposed algorithm categorizes WMSNs traffic into six different classes. The algorithm takes a novel and different approach towards congestion control in WMSNs. Upon detection of congestion, the congested node makes an estimate of the data rate that should be used by the node itself and its one hop away upstream neighbours. While estimating the data rate, the congested node considers the characteristic of the different traffic classes along with their total bandwidth usage. An example illustrates the operation of the proposed algorithm and theoretical results show that the proposed algorithm performs better than an existing congestion control algorithm for WMSNs