The INCA (Integrated Network Communications Analysis) model

In 1985 British Aerospace identified the need for a generalised communications network model, capable of analysing communications between interconnected networks using alternate transmission media. Applications were apparent for the analysis of C³I in air defence studies, maritime scenarios, etc. The initial objective of the model was both to assist in the design of a specific network and to analyse any aspects of the performance of multinetwork systems. INCA is an event-stepping, stochastic model, monitoring the passage of a `wanted message´, in relation to the competing traffic, across a system of connected networks. The model is designed to cater for any combination of circuit, packet, message switched or broadcast networks, with associated time delays for reconfiguring messages that are being transferred between alternate types of network. Traffic in the system, other than the `wanted messages´, the `background traffic´, is defined as a particular level of erlang traffic, between pairs of nodes (termed a needline) within each network