Functions within the Data Communication Layers of the ISO Open Systems Interconnection (OSI) Model

摘要

Two service types for the data-communication layers of the ISO-OSI model: the connectionless and the connection-oriented service, are discussed. The main difference between these service types is that the latter incorporates a three party negotiation phase. Although connection-orientation is one of the basic ideas behind the reference model for open system interconnection, the connection approach may not be the best for all data-communication layers. Many functions within these layers can also be performed with a connectionless service type. It is argued that it is possible with a connectionless network service to avoid congestion.