標準號：ONORM ENV 41801-5-1993
中文標準名稱：信息系統互連．無連接式網絡服務用繼電器．RC51．1121文件(M－IT－02R/21)
英文標準名稱：Information systems interconnection - Relaying the connectionless-mode network service - Profile RA51.51 (M-IT-02R/21)
發布日期：1993/1/1 12:00:00
實施日期：1999/12/31 12:00:00
適用范圍：1.1 GeneralThis Functional Standard is applicable to interworking units concerned with operating in the Open Systems Interconnection (OSI) environment. It specifies a combination of OSI base standards that collectively provide a Network-relay function for the Connectionless-mode Network Service.This part of this Functional Standard defines the R/A61.51 profile, which is applicable to interworking units operating between CSMA/CD LAN subnetworks.1.2 Position within the TaxonomyThe taxonomy of profiles is defined in M-IT-02. This part of this Functional Standard defines the profileR/A51.51 Relaying the Connectionless-mode Network Service between CSMA/CD LAN subnetworks.1.3 ScenarioFigure 1 illustrates the configuration of systems to which the R/A51.51 profile is applicable. The figure shows two reference points, but an implementation of this profile may include any number of CSMA/CD LAN attachments, with a reference point corresponding to each.