Hostile Operating Environment

There is a need to understand the tactical operating environment in order to appreciate its characteristics in deploying robust communication networks. In such a hostile environment network condition is very unstable. Instability can interrupt communications and some crucial information may be lost. Instability in a hostile environment is caused by the following key factors:

High node mobility

In tactical missions, nodes are characterized by high random mobility. As a wireless node cannot communicate with another unless it's within its radio range, a node moving beyond the radio range of other nodes loses connection to the network. The mobility of nodes directly affects the availability of communication paths between nodes.

Intermittent Interferences

Multi-path propagation, noise, and nearby frequencies. cause signal-to-interference-plus-noise ratio (SINR)degradation. Hence packet may be lost if interferences and noise are stronger than the signal. Interferences in hostile environments are very intermittent due to terrain types and dynamic movement of the node. A tactical wireless network is operating in various types of terrain; i.e. urban, forest, hill, and sea. These different terrains produce different interference characteristics on a tactical wireless network. Because of the dynamic movement of military force and network operation of nearby forces, the interference in a tactical wireless network has intermittence behavior.

Hostile Attack

The hostile attacks on tactical wireless networks include physical attacks and electronic attacks. A physical attack may be an attack that directly causes physical damages on a mobile node, this node will not be able to communicate and disappear from the network. Several electronic attacks exist such as jamming, denial of services or flooding. A hostile node may forge as a regular node, and steal or drop information flowing in a network. These attacks may shut down mobile nodes from communication permanently or temporarily, which causes instability in a tactical wireless network. An interrupted mobile node can be modeled as a disappeared node, in which it cannot send or receive any data during the interruption.