# Intelligent Communication in Wireless Sensor Networks
## Related Work  
### Classification of Routing Protocols  
Large amounts of data need to be processed because of the deployment of a large amount of smaller and less expensive sensors in a sensor array. Therefore, routing (which is the routing of data from a sender to a destination) is a very important service in these networks. The goal of routing is to establish efficient paths between sensors so that messages can be delivered when needed.  
Routing is the method of transporting data to the right destination through a network. The goal of routing is to find the least expensive investment in nominal and standby capacity that routes traffic and ensures its survival before any link or sensor failure.  
The most energy-efficient protocols rely on routing and consider very specific characteristics of this type of network. Limited energy resources and computing energy of the sensors requires a new generation of protocols different from those of wired networks [3]. This difference can be explained, on the one hand, by the impossibility of having a global addressing with the routing tables as in the IP networks, given the large number and the density of deployment of the sensors. On the other hand, communication is more important in one direction: several sensors send their data to the sink. In addition, the data transmitted are often highly correlated, which requires a specific operation to optimize bandwidth and energy consumption. Finally, sensors are limited in energy, computing power and storage capacity; this requires efficient resource management.  
To overcome these constraints, several routing solutions have been proposed, and can be grouped according to several criteria [3; 4; 5; 6], namely the topology of the network, the operations supported [5; 6] and the destination of transmitted packets [6]. The adopted network topology divides routing solutions into three main forms: flat topology protocols, hierarchical protocols, and geographic protocols. Moreover, if the supported operations are maintained, we can classify the solutions into multipath-based, query-based, negotiation-based, solutions based on the qualities of the service, and solutions based on the destination of the transmitted packets [3]. The last classification criterion distinguishes the solutions proposed as [5]: the uncast communication, or the destination of the message, is a single sensor, the multicast communication, or the recipients of the message are a defined subset of the network, and broadcast the communication, where the message is intended for the whole network [7].  
Among the classifications mentioned above, the first is the most found in the fourth-class enriched literature that deals with quality of service based protocols. Flat topology protocols, which can be query-based, use a naming system to specify the required data that restricts redundant data submissions. The global network is restructured by hierarchical protocols into groups called clusters or sectors. Clusters are each represented by a cluster-head that aggregates and reduces the size of the transmitted data to save energy. Geographic protocols use the geographical position of sensors to guide data transmissions to desired regions of the entire network. The last category, based on the quality of service includes some communication skills in addition to data routing.