Industrial Automatic Control Systems and Controllers Annotation << Back Model of Heterogeneous Local Communication Network with Combined Access Protocol, Considering the Reliability of its Elements E.B. Gezalov In the article the local communication network, heterogeneous on the intensity of the incoming message flow and the type of messages, with combined access protocol is considered. All communication stations of the considered local network consist of three substations: speech substations, video information substations and data substations. Speech substations form the speech subnet, video information substations form the video information subnet, and data substations form the data subnet. Substations within the same subnet are homogeneous in their activity. A model of the considered local network in discrete time is being carried out, which allows assessing the eff ect of the failure processes and restoration of substations of network stations and the communication channel on its characteristics. Keywords: heterogeneous local area network; combined access protocol; substation; subnet buffer; frame; time window; service interval. DOI: 10.25791/asu.9.2020.1220 Pp. 47-52.