CEPT T SF 38 E-1985 Communications Requirements for Personal Computers《个人电脑通讯要求》.pdf

1、- i CEPT T/SF*38*E 85 m 2326434 0009366 9 m % T/SF 38 E Page 1 , Recommendation T/SF 38 E (Nice 1985) concerning the communications requirements for personal computers Recommendation proposed by Working Group T/WG 7 “Services and facilities” (SF) Text of the Recommendntion ndopted by Commission “Tel

2、ecomrniiicntiois: “The European Conference of Posts and Telecommunications Administrations, Consideriiig - that personal computers (PC) in Europe have achieved, or are achieving, a significant penetration in the business environment and in the home; - that whilst a primary reason for purchasing PCs

3、is to undertake stand alone computing, and more and more PCs are being purchased to form part of a network (multi-tasking, etc.); - that there is also an increasing demand for the communication of computer files, text and programs between stand alone PCs or between PCs on different networks; - that

4、PCs are, and will be used for different applications each with their specific requirements for communications e.g. - in the business application where official (company) messages and documentation need to be exchanged: the quality of the communication needs to be high in terms of availability, repro

5、ducibility and freedom from o errors, - in the household and informal business applications : the quality of the communication needs may be low, direct terminal to terminal communication is needed infrequently, often communication takes place via a computer based message system (CBMS); - that this d

6、emand for communication is a market as yet untapped by administrations (PTTs) and represents a - that, at present, growth is inhibited by a lack of suitable standards; - that pressure for standards is mounting and de facto standards could emerge; - that de facto standards for PC communication are un

7、likely to be compatible with open system interconnection - that this situation will encourage a separate market to develop for PC communication which will to some extent - that the development of communications standards for PCs which are compatible with, or can interwork with, potentially huge sour

8、ce of new telecommunications trafic; (OW ; compete with PTT provided telematic services; the telematic services will: encourage PC users to communicate via PTT telematic services, promote intenvorking with PTT telematic services, assist in creating a larger market from which PC customers, suppliers

9、and PTTs will benefit; distribution of traffic/message transfer could also imply data and text networks. o - that present solutions for communicating PCs often imply the use of the PSTN whereas a more optimal Recommends - that CEPT PTTs should provide support for personal computer communications whi

10、ch enable PCs to communi- cate with each other and with the telematic services via the Message Handling Service (MHS) and which are: easy to use, easy to implement, cheap to implement; Edition of November 30, 1985 CEPT T/SF*38*E 85 W 2326414 00093b7 O W! T/SF 38 E Page 2 - that the PC communications

11、 support should provide at least the following facilities: data rates of 300 and 1200 bit/s full duplex on the PSTN, support of simple PCs access protocols to MHS, minimal error recovery, a simple character repertoire based on CCITT Recommendation V.3, an image format based on teletex IS0 A4 option

12、(portrait only), allow interactive working with videotex services, allow auto receiving, allow the exchange of files via MHS.” Note: It is expected that, when an equivalent CD/SE Technical Recommendation is developed, it will be associated with this Service Recommendation. Edition of November 30, 1985