... the combined effects of three communicating EFSMs. The issue at hand is: Is it necessary to develop a complete composite state machine to correctly model PNNI, and if so, how? Furthermore, since a PNNI system represents an ATM network switching node, within a network switching nodes are expected to interact with each other. Therefore what is the minimum number of nodes needed to correctly simulate the operation of PNNI? In our study, we take two nodes connected by a full-duplex channel, based on the following observations. We want to detect design/specification errors from verification, implementation errors from conformance testing, and errors from both the design and implementation from interoperability testing. Suppose that an error is revealed using a two-node model, then obviously, faults in the specification are detected. Conversely, suppose that there are faults in PNNI in a multiple node network. Since it is a hierarchical protocol, we can group ...

See this essay or coursework document in full right now