Congestion Control and Traffic Management in Wireless Sensor Networks Wireless Sensor Networks (WSNs) have a wide range of scientific and commercial applications. However, these networks have several topologyrelated problems such as is the bottlenecks around the sink, which is caused by multihop relaying where sensor nodes around the sink relay data that is generated all over the network. This could create congestion which results in packet loss, and also affect the network lifetime as these sensors deplete their energy much faster than other ones. In this paper, we show how the packet arrival rate as a measure can help in controlling congestion. This done using Fast Congestion Notification (FN) queue management mechanism at the data collectors of the network. The results confirmed that FN controls the packet arrivals better than Random Early Detection (RED) and minimizes the global synchronization.

Colored Petri Nets for Modeling Congestion Control in Wireless Sensor Networks with Retrials Wireless sensor networks with their resources constraint lead to congestion, which has a meaningful negative impact on performance and QoS of these networks, so congestion control is one of the most important challenges. In this paper, we present a queuing and service management for congestion control with a retrial system called QSMCCR. In our model, two logical queues characterize a sensor node, the first is used to store control packets and the second one for data packets. The approach is based on Round Robin policy to serve packets and uses control packets to acknowledge received data packets or to inform other nodes about the congestion if the queue occupancy rate reaches a threshold. Considering two levels of data packets which can transit through the network, QSMCCR can be more reliable according to the field of application. In addition, we show a method for modeling and analyzing queuing and service management with a retrial system using Colored Petri nets.