標準號：ONORM ENV 41211-1-1993
中文標準名稱：信息系統互連．虛擬終端． 基本類型．A模式X．3．虛擬終端服務
英文標準名稱：Information Systems Interconnection -Virtual Terminal -Basic class - A-mode X.3 - Virtual terminal service
發布日期：1993/2/1 12:00:00
實施日期：1999/12/31 12:00:00
適用范圍：This Functional Standard provides a method of interactive operation using OSI Virtual Terminal Service and Protocol which is equivalent to the CCITT X.3 PAD functionality and X.29 protocol commonly used over virtual circuits of X.25 packet switched networks. It includes a modelling of the X.3 PAD Parameters and associated X.29 operations using VT concepts.This Functional Standard supports applications where the terminal representation of the interactive data stream is character orientated and where the terminal end system is associated with a function equivalent to an X.3 PAD as defined in the CCITT Recommendations. This Functional Standard only supports a transparent repertoire since X.3 and X.29 do not support character repertoire declaration. This Functional Standard does not constrain the syntax or semantics of information transferred in this transparent repertoire syntax.This Functional Standard does not include a specification of those capabilities of the Virtual Terminal that must be realised in the real terminal device since again X.3 and X.29 do not provide any similar facilities. It is expected that users of this Functional Standard will wish to agree the capabilities of the real device by means outside the scope of this Functional Standard.Reference to ENV 41901 may be useful for the information and guidance it gives on the use of the X.3 PAD Parameter values.