1、STD-ITU-T RECMN F-59-ENGL 1976 M 48b2591 Ob32173 728 INTERNATIONAL TELECOMMUN CATION UNION ITU=T TELECOMMUNICATION STAN DARDI ZATI ON SECTOR OF ITU F.59 (I 0/96) SERIES F: NON-TELEPHONE TELECOMMUNICATION SERVI CES Telegraph service - The international telex service General characteristics of the int
2、ernational telex service ITU-T Recommendation F.59 (Previously CCITT Recommendation) STDmITU-T RECMN F-57-ENGL L77b 48b257L Ob32174 bb4 KU-T F-SERIES RECOMMENDATIONS NON-TELEPHONE TELECOMMUNICATION SERVICES TELEGRAPH SERVICE Operating methods for the intemational public telegram service The gentex n
3、etwork Message switching F. 1-F.109 F. 1-F. 19 F.20-F.29 F.30-F.39 Statistics and publications on international telegraph services Scheduled and leased communication services F.90-F.99 F. 100-F. 104 Phototelegraph service Mobile services and multidestination satellite services MOBILE SERVICE TELEMAT
4、IC SERVICES , Public facsimile service Teletex service Videotex service General provisions for telematic services MESSAGE HANDLING SERVICES DIRECTORY SERVICES DOCUMENT COMMUNICATION Document communication Programming communication interfaces DATA TRANSMISSION SERVICES AUDIOVISUAL SERVICES ISDN SERVI
5、CES UNIVERSAL PERSONAL TELECOMMUNICATION HUMAN FACTORS F.105-F.109 F.llO-F.159 F.llO-F.159 F.160-F.399 F. 160-F. 199 F.200-F.299 F.300-F.349 F.350-F.399 F.400-F.499 F.500-F.549 F.550-F.599 F.550-F.579 F.580-F.599 F.600-F.699 F.700-F.799 F. 800-F. 849 F.850-F.899 F.900-F.999 Il For further details, p
6、lease refer to ITU-T List of Recommendations. FOREWORD The IT-T (Telecommunication Standardization Sector) is a permanent organ of the International Telecommunication Union (ITU). The IT-T is responsible for studying technical, operating and tariff questions and issuing Recommen- dations on them wit
7、h a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Conference (WTSC), which meets every four years, establishes the topics for study by the IT-T Study Groups which, in their turn, produce Recommendations on these topics. The approval of Rec
8、ommendations by the Members of the IT-T is covered by the procedure laid down in WTSC Resolution No. 1 (Helsinki, March 1-12, 1993). ITU-T Recommendation F.59 was revised by ITU-T Study Group 1 (1993-1996) and was approved by the WTSC (Geneva, 9-18 October 1996). NOTE In this Recommendation, the exp
9、ression “Administration” is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. O ITU 1997 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mecharlical, including photocop
10、ying and microfilm, without permission in writing fiom the ITU STD-ITU-T RECMN F-57-ENGL L77b 48b259L Ob32L7b 437 = CONTENTS 1 Introduction 1.1 Scope General characteristics of the international telex service . Operational aspects and basic characteristics of telex terminals derived from the service
11、 principles . 3.1 Permanently ready to receive 3.2 Automatic print-out on continuous paper (e.g. roll) . 3.3 Effect on telex connections due to failures of resources . 3.4 Answerback unit . 3.5 Character set and character presentation . 3.6 Special character sequences 3.7 Presentation of messages at
12、 sending and receiving terminals . 3.8 Conversational mode 3.9 Stop of transmission by backward signals 3.10 Verification of text 4 References 4.0 Definitions 4.1 Basic characteristics of the international telex service . 4.2 Additional facilities of the international telex service 4.3 4.4 4.5 4.6 2
13、 3 Charging and accounting, Quality of Service, statistics . Service oriented network aspects Mobile services (maritime, satel1ite)Radiotelex Intenvorking with other services Page 1 1 1 2 2 2 2 2 3 3 3 3 3 3 3 5 5 5 6 6 7 7 STD-ITU-T RECMN F-57-ENGL 177b m 48b2571 Ob32177 373 m Recommendation F.59 G
14、ENERAL CHARACTERISTICS OF THE INTERNATIONAL TELEX SERVICE (revised in 1996) 1 Introduction 1.1 Scope This Recommendation summarizes the service Characteristics of the international telex service and the service-related basic characteristics of telex terminal equipment. 1.2 common understanding of th
15、is service, bearing in mind: This summary of all service-related principles for the international telex service is intended to facilitate a - that the intemational telex service is the only text communication subscriber service available throughout the world; - that the perceived special merits of t
16、his service are its technical reliability and operational simplicity; - that the operational provisions for the intemational telex service can be found in Recommendation F.60, but other service principles and service-oriented network and terminal characteristics have to be selected from a number of
17、F-, R-, S- and U-Series Recommendations in addition. 1.3 with other services. This summary should also be the basis for all considerations of interworking of the international telex service 2 General characteristics of the international telex service The international telex service is a service prov
18、ided by telecommunication Administrations of almost all countries of the world for the purpose of text communication. In its basic form, it is used for directly transmitting telex messages between subscriber terminal equipment connected to the telex network or to/fiom public telex stations. In the i
19、nternational telex service: 2.1 The text of the transmitted and received message is identical with respect to the character sequence in a line and to the line sequence. There is no defined limit on the length of a telex message. There is no “page” defined in the service. 2.2 No. 2 (ITA2) and a maxim
20、um line length of 69 spacing characters per line. Basic characteristics of telex messages are the character repertoire of the International Telegraph Alphabet 2.3 structure of 7 1/2 elements per character at a modulation rate of 50 bauds (i.e. 6 2/3 characterskec.). Communication is by using half-du
21、plex, asynchronous (start-stop) transmission, operating with a character 2.4 Switched connections are used in the telex networks. 2.5 Continuous availability of the service, 24 hours a day, in principle, is given. 2.6 Telex terminals must be ready to receive messages, even if they are unattended or
22、used in local mode. 2.7 An answerback unit allows the identification of the telex terminals during the whole process of communication. At the beginning and at the end of each telex connection the exchange of answerback codes between transmitting and receiving telex terminals is recommended. STD-ITU-
23、T RECMN F-59-ENGL 199b 48bZ.571 Ob32178 ZUT M 2.8 form and sequence as the messages are transmitted over the line is traditionally recognized as a basic feature. The automatic print-out of messages on continuous paper at the transmitting and receiving terminal in the same 2.9 operators of the telex
24、terminals. Another important feature is the possibility of a direct character-by-character conversation between the NOTE - There are telex terminals for which this is not possible, that is where “Conversation Impossible” (CI) is applied. 3 Operational aspects and basic characteristics of telex termi
25、nals derived from the service principles 3.1 Permanently ready to receive Telex terminals must be available to receive messages both whilst in unattended mode or being operated in local mode. This includes the automatic return of the answerback code in response to a WRU signal. There is automatic re
26、covery to this state after a power or line failure. 3.2 Automatic print-out on continuous paper (e.g, roll) Telex messages, as traditionally recognized, are printed at the sending and receiving terminals in the character and line sequence and in the chronological order in which they are transmitted
27、over the line. If character-by-character printing is not used, then print-out should be no later than immediately after the connection is released. If sendreceive buffers are used, these, before print-out, must be non-volatile and not accessible, changeable or removable by the operator. 3.3 Effect o
28、n telex connections due to failures of resources Prevent establishment or cause clear-down of established connections in case of: end of recording media, power failure. 3.4 Answerback unit The answerback unit is permanently ready to send the answerback code on local or remote request. It is protecte
29、d from access by the operator. Answerback codes exchanged by transmittingreceiving terminals during a connection must be printed in chronological order together with the associated telex message. A message prepared for automatic transmission must not contain a WRU combination, unless there is suffic
30、ient pause in transmission to receive an answerback after sending a WRU. STDmITU-T RECMN F.59-ENGL L99b 48b259L Ob32197 14b 3.5 The ITA2 character set is used. Character set and character presentation Character presentation is either entirely upper-case or entirely lower-case, but not mixed. Recepti
31、on of the “bell” signal causes an instant audible signal (operator alarm). 3.6 Special character sequences Special character sequences which invoke network responses should not be used within telex messages. Other special character sequences should only be used for their defined purposes. 3.7 Presen
32、tation of messages at sending and receiving terminals The complete printable ITA2 character set must be represented. There is a maximum of 69 spacing character positions per line. No page format is defined. 3.8 Conversational mode Character-by-character conversation must be possible, with the except
33、ion of terminals responding to a “bell” signal with “Ci”. Printed documentation of conversational messages should normally be available. Transmitted and received characters should be represented differently for distinction (Le. by shape, colour, etc.). ITA2 control characters must be available to th
34、e operator. There is a manual clear-down facility. The operator at the receiving terminal must also be able to clear down a connection. A called telex terminal must not start automatic transmission without being requested to do so by the operator of the calling terminal. 3.9 Stop of transmission by
35、backward signals The operator at the receiving terminal should be able to stop the reception of an automatic transmission by transmitting the character sequence TTT. 3.10 Verification of text Means of verieing the text to be transmitted (in the format to be sent over the line) should be provided: -
36、prior to transmission when sending from memory; or during transmission when sending from the keyboard. - 4 References For detailed information on the service aspects of the international telex service, the following references are given (see also Figure 1): STD-ITU-T RECMN F.59-ENGL L77b 48b257L Ob3
37、2200 778 International telex service Charging accounting statistics r other services facilities radiotelex Definitions I S 15 s.ll R.140 Annexe BIF.60 F.83 - F.82 - Basic characteristics F.72 , +TJ s.20 - F.74 - s.9 S.8 S.6 - s.5 - s.4 - s.l - F.68 - F.65 - I F.69 - J F.60 - F.59 - I F.30 r - F.71 -
38、 - - F.63 , , ,sfJY s.19 - F.80 F.127 Draft Recommendation Figure 1E.59 - International telex service -Family of Recommendations STD-ITU-T RECMN F-59-ENGL 1996 9 48b257L Ub3220L b24 9 4.0 Definitions - CCITT Recommendation R.140 (1988), Dejhitions of essential technical terms in the field of telegra
39、ph transmission. - CCITT Recommendation S.140 (1988), Definitions of essential technical terms relating to apparatus for alphabetic telegraphy. CCITT Recommendation U. 140 (1988), Definitions of essential technical terms relating to telegraph switching and signalling. CCITT Recommendation F.60 (1992
40、), Operational provisions for the international telex service. (Annex B). - - 4.1 Basic characteristics of the international telex service - - - - - ITU-T Recommendation F.59 (1996), General characteristics of the international telex service. CCIT Recommendation F.60 (1 992), Operational provisions
41、for the international telex service. CCITT Recommendation F.65 (1988), Time-to-answer by operators at international telexpositions. CCITT Recommendation F.68 (1988), Establishment of the automatic intercontinental telex network. ITU-T Recommendation F.69 (1994), The international telex service - Ser
42、vice and operational provisions of telex desination codes and telex nerwork identijkation codes. ITU-T Recommendation S.l (1993), International Telegraph Alphabet No. 2. IT-T Recommendation S.4 (1993), Special use of certain characters of the international Telegraph Alphabet No. 2. - - - CCITT Recom
43、mendation S.5 (1 980), Standardization of page-printing start-stop equipment and cooperation between page-printing and tape-printing start-stop equipment (ITAZ) . CCITT Recommendation S.6 (1984), Characteristics of answerback units (iTA2). ITU-T Recommendation S.8 (1 993), Intercontinental standardi
44、zation of the modulation rate of start-stop apparatus and of the use of combination No. 4 in figure-shift. CCITT Recommendation S.9 (1988), Switching equipment of start-stop apparatus. ITU-T Recommendation S.20 (1993), Automatic clearing procedure for a telex terminal. ITU-T Recommendation U. 1 (199
45、3), Signalling conditions to be applied in the international telex service. ITU-T Recommendation U.45 (1993), Response io the not-ready condition of the telex terminal. - - - - - - 4.2 Additional facilities of the international telex service - - - ITU-T Recommendation F.72 (1996), The international
46、telex service - General principles and ITU-T Recommendation F.30 (1993), Use of various sequences of combinations for special purposes. ITU-T Recommendation F.63 (1993), Additional facilities in the international telex service. operational aspects of a store and forward facility. CCITT Recornendatio
47、n S.11 (1980), Use of start-stop repeflorating equipment for perforated tape retransmission. - - - CCITT Recommendation S.15 (1968), Use of the telex network for data transmission at 50 bauds. ITU-T Recommendation S.16 (1993), Connection to the telex network of an automatic terminal using a Y24 DCE/
48、DTE interface. CCITT Recommendation S. 17 (1 968), Answerback unit simulators. - STD-ITU-T RECMN F.59-ENGL L99b = 48b2571 Ob32202 5bO - CCITT Recommendation S.19 (1980), Calling and answering in the telex network with automatic terminal equipment. ITU-T Recommendation S.21 (1993), Use of display scr
49、eens in telex machines. ITU-T Recommendation S.22 (1993), “Conversation impossible” and or pre-recorded message in response to J/BELL signalspom a telex terminal. ITU-T Recommendation S.23 (1993), Automatic request of the answerback of the terminal of the calling party, by the telex terminal of the calledparty or by the international network. ITU-T Recommendation U.40 (1993), Reactions by automatic terminals connected to the elex network in the event of ineffective call attempts or signalling incidents. CCITT Recommendation U.41 (1988), Changed address interception and call redir
