標準號：SIS SS 63 63 02-1986
中文標準名稱：信息處理系統（MHS）．基本服務內容和可選用戶設備
英文標準名稱：Message handling systems (MHS) - Basic service elements and optional user facil ities
發布日期：1986/11/15 12:00:00
實施日期：1999/12/31 12:00:00
適用范圍：This Recommendation is one of a series of Recommendations and describes the basic service elements and the optional user facilities of the Message Handling System (MHS). MHS service elements are provided by means of the Interpersonal Messaging (IPM) and Message Transfer (MT) Services. This Recommendation overviews those services and categorizes the optional user facilities of each. Locally provided service elements, for which communication with other users is not required, are not covered by this Recommendation.Other Recommendations in the series contain additional information essential to a thorough understanding of the IPM and MT Services. Recommendation X.400 describes the MHS model and defines the IPM and MT service elements. Recommendation X.408 specifies the algorithms that MHS uses when converting between different types of encoded information. Recommendation X.409 defines the notation and the representational technique used to specify and encode MHS protocols. Recommendation X.410 describes general techniques used for MHS protocols and the way in which Standard Open Systems Interconnection (OSI) protocols are used to support MHS applications. Recommendation X.411 specifies the protocol aspects of the MT Service. Recommendation X.420 specifies the protocol aspects of the IPM Service. Recommendation X.430 describes how teletex terminals access the MHS.Some service elements are inherent in the MHS; these constitute the basic IPM and MT services. Additional service elements, called optional user facilities, may be selected by the subscriber or user, either on a per-message basis or for an agreed contractual period of time. Each optional user facility visible to the user is classified as either essential or additional. Essential (E) optional user facilities are to be made available internationally by Administrations. Additional (A) optional user facilities may be made available by some Administrations for national use and may also be available internationally on the basis of bilateral agreement.The MHS is designed in accordance with the principles of the Reference model of open systems interconnection for CCITT applications (Recommendation X.200), and thus can be constructed using any physical network. The IPM and/or MT Services may be offered separately or in combination with various telematic services (Recommendations F.160, F.200, F.300) or data communication services (Recommendations X.l, X.2, X.10 + V Series). They can be obtained by making appropriate arrangements.