Cognitive Networks: Towards Self-Aware Networks

3.4. Representative Adaptation Techniques

Changes in dynamic factors can adversely affect the four common network functions described in Section 3.3. To mitigate the impact of those changes, researchers have proposed and developed various mechanisms addressing changes in different dynamic factors. This section introduces typical adaptive techniques by presenting and discussing representative schemes that adapt to various dynamic factors for each of the four common network functions.

3.4.1. Constructing Hop-by-Hop Connectivity

Constructing hop-by-hop connectivity establishes a connected network topology, which allows data to be routed between any pairs of nodes in the network. A connected topology should enable data routing that satisfies a set of user requirements, such as transmission latency, load balance and energy efficiency. However, changes in a network environment may cause connectivity between nodes to degrade or fail. Therefore, a network needs to adapt to changes in dynamic factors while constructing hop-by-hop connectivity.

Nodes adapt to changes in dynamic factors that affect topology connectivity in the following manner. First, nodes obtain information regarding their neighboring nodes. For example, nodes may acquire residual energy of a neighboring node, capacity of a link to a neighboring node, and/or distance to a neighboring node. Second, based on the obtained information, nodes evaluate their neighboring nodes according to certain criteria. For example, nodes ...