1、INTERNATIONAL TELECOMMUNICATION UNION)45G134 4 TELECOMMUNICATIONSTANDARDIZATION SECTOROF ITU4%2-).!,G0G0%15)0-%.4G0G0!.$G0G002/4/#/,3G0G0b) when the CF and Teletex terminal are in different countries, with message transfer in the CF to Teletexterminal direction. This is subject to bilateral agreemen
2、t.Note 1 Due to practical operational difficulties such as charging, message transfer in the direction from aTeletex terminal to a CF in another country is not considered in this Recommendation.Note 2 The requirements of interconnection of CFs for the international interworking between Teletex andte
3、lex services are for further study.Note 3 The real-time conversion operation is not considered in this Recommendation.1.1.7 The provisions in this Recommendation are independent of the means and procedures for communicationbetween the CF and the telex network. These are covered in Recommendation F.2
4、00.1.2 Basic Teletex/telex interworking model1.2.1 As illustrated in Figure 1/T.390 and in the single-message case, the communications between a CF and aTeletex terminal for the transfer of a message from Teletex to telex may consist of two calls, namely:a) a submission call initiated by a Teletex t
5、erminal to transfer to the CF a message prepared in the telex modeas per Recommendations F.200 and T.60, and related control information;b) a notification call initiated by the CF in which delivery or non-delivery information may be provided. Thiscall is mandatory if the telex call is unsuccessful b
6、ut optional if the telex call succeeds.2 Fascicle VII.5 - Rec. T.3901.2.2 As illustrated in Figure 2/T.390, the communications between a CF and a Teletex terminal for the transfer of amessage from telex to Teletex may consist of two calls, namely:a) an address validation call initiated by the CF to
7、validate the called Teletex number. The requirement forthis call is a national matter;b) a delivery call initiated by the CF to transfer to the Teletex terminal a message received from the telexterminal.1.2.3 For transferring additional control information between the Teletex terminal and the CF, co
8、ntrol documents areused. A control document may be associated with one or more normal documents. This set will be called a message.All these normal documents should be in telex mode and shall be delivered by the CF as a single telex message. Thecontrol document need not be prepared in telex mode. An
9、 acknowledgement control document will refer to a messageand not to individual documents.2 Session elements of procedure2.1 The session elements of procedure shall be in accordance with Recommendation T.62. However, the followingqualifications shall apply:2.1.1 The values of mandatory parameters use
10、d during session establishment shall be as given in Table 1/T.390.Fascicle VII.5 - Rec. T.390 32.1.2 The value of the “terminal identifier of the calling terminal” parameter in the CSS of the delivery call dependson whether the CF and Teletex terminal are in the same or different countries.2.1.2.1 W
11、hen the CF and Teletex terminal are in the same country, it may be either the terminal identification of the CFor, alternatively, the terminal identifier derived from the calling telex answerback (A/B) in one of the following formsin which optional fields are enclosed in parentheses:8 = 8 = 8 ( ) =
12、()Note 1 is the value of the answerback received from the telex terminal after the deletion of the CR LFcharacters, if present.Note 2 is the value of the Recommendation F.69 “telex destination code” of the originating network.Note 3 is the subscriber number part of the received , as described in Not
13、e 1, whichconforms to Recommendation F.60.Note 4 is the optional machine identity part of the received , as described inNote 1, which conforms to Recommendation F.60.Note 5 is the optional subscriber name part of the received , as described inNote 1, which conforms to Recommendation F.60. This may a
14、lso include the telex network identification code.TABLE 1/T.390Mandatory parameter values during session establishmentT.62 parametersCall typeSubmission Notification Address validation DeliveryTerminal identifier of thecalling terminal (in CSS)TTXs TID CFs TID CFs TID See 2.1.2Terminal identifier of
15、 thecalled terminal (in RSSP)CFs TID TTXs TID TTXs TID TTXs TIDDate and timeSubmission calloriginating date andtime by TTXNotification calloriginating date andtime by CFAddress validationcall originating dateand time by CFDelivery calloriginating date andtime by CFService identifier Teletex Teletex
16、Teletex TeletexTID Terminal IdentificationTTX Teletex TerminalCF Conversion facility2.1.2.2 When the CF and Teletex terminal are in different countries, it shall be the terminal identification of the CF inaccordance to the format specified in Recommendation F.201. The calling telex answerback shall
17、be contained in thetext of the normal document in the format and at the point at which it was obtained by the CF.4 Fascicle VII.5 - Rec. T.3903 Document elements of procedures3.1 General3.1.1 The document elements of procedure shall be in accordance with Recommendation T.62. In addition, theTeletex
18、terminal and the CF shall be able to handle control documents defined in this Recommendation as shown inTable 2/T.390.4 Control documents4.1 For transferring additional control information between the Teletex terminal and the CF, control documentsare used. The additional control information is conta
19、ined in the user information part of the control document and iscalled “control text”. A summary of the control documents is given in Table 2/T.390.TABLE 2/T.390Control documents for Teletex/telex interworking serviceType of call (see Figures1/T.390 and 2/T.390)Control document Status of control doc
20、umentCF Telex terminalTelex to telex message transferSubmissionNotificationTelex submissionTelex delivery notification(Note 2)Telex non-deliverynotification (Note 2)MandatoryMandatoryMandatoryMandatorySelectableMandatoryTelex to telex message transferAddress validationDeliveryTelex validation (Note
21、1)Telex message deliveryOptionalOptionalOptionalOptionalMandatory: Shall always be implemented.Optional: Shall be implemented according to national requirements.Selectable: To be implemented as appropriate.Note 1 An address validation call need not contain a telex validation control document.Note 2
22、At present, this only relates to a single telex address.4.2 Telex submission control document4.2.1 The Telex submission control document shall be used by the Teletex terminal to indicate to the CF that theassociated subsequent normal document(s) is to be transferred to a telex terminal.4.2.2 Element
23、s of the control text are:a) control document identifier mandatory;b) submission control information optional.This element consists of the following parameters:Fascicle VII.5 - Rec. T.390 5i) telex address optional.This is the address of the recipient. It need not be present if provided in lower lay
24、er procedures;ii) answerback optional.This is the expected telex answerback. It is to be provided if automatic check by the CF is required;iii) acknowledgement request optional.This is the request for telex delivery notification. This parameter is only present if the user requiresadvice of a success
25、ful telex call. It need not be present in cases where the CF always providesdelivery notification.4.2.3 This control document may be utilized in multi-addressing by providing several sets of the submission controlinformation element in 4.2.2 above. The provision of this capability in a CF is a natio
26、nal matter.Note The inclusion of Teletex addresses within the multi-addressing list is for further study.4.2.4 Multiple telex submission control documents (each with associated normal documents) may be used within thesame session. The provision of this capability in a CF is a national matter.4.3 Tel
27、ex delivery notification control document4.3.1 If the Teletex user requires notification after the successful message transfer to the telex terminal see 4.2.2b), then the telex delivery notification control document shall be sent by the CF to the originator of the telex message.As a national matter,
28、 some CFs may always provide this delivery notification.4.3.2 Elements of the control text are:a) control document identifier mandatory;b) correlation information mandatory.This provides a unique reference to the corresponding telex submission control document. The elementparameters which are provid
29、ed by the CF are a national matter. These parameters are: CF TIDThis is the terminal identification of the CF to which the corresponding telex submission controldocument was sent. TTX TIDThis is the terminal identification of the Teletex terminal which sent the telex submission control document. Dat
30、e and timeThis is the date and time of the submission call. CD No.This is the document reference number of the telex submission control document. Addl session Ref No.This is the additional session reference number if used in both the CSS and RSSP in the submissioncall;c) submitted control informatio
31、n mandatory.This reflects the relevant parameters of the telex submission control document pertaining to a singleaddress. These parameters are: telex addressNote This parameter can be derived from lower layer procedures if not present in the telex submissioncontrol document. answerback acknowledgeme
32、nt request;6 Fascicle VII.5 - Rec. T.390d) delivery information mandatory.This provides information concerning call establishment from CF to the called telex terminal. The elementparameters which are provided by the CF are a national matter. These parameters are: telex addressThis is the address der
33、ived from the telex submission control document and used by the CF to establishthe call.Note This parameter can be derived from lower layer procedures if not present in the telex submissioncontrol document. received answerbackThis is the complete telex answerback as received by the CF;e) time of del
34、ivery optional.This is the time at which the CF delivered the telex message to the telex terminal;f) telex transmission duration optional;g) note optional.This is used to convey additional information;h) received recorded message optional.This is used to convey to the Teletex terminal any recorded m
35、essage from the telex destination.4.4 Telex non-delivery notification control document4.4.1 The telex non-delivery notification control document shall be used in the following cases:a) if a telex message cannot be delivered;b) if a telex message was only partially delivered;c) if a message is incomp
36、letely received in the CF and this partial message successfully delivered (see 6.1.2).4.4.2 Elements of the control text are:a) control document identifier mandatory;b) correlation information mandatory see 4.3.2 b);c) submitted control information mandatory see 4.3.2 c);d) delivery information mand
37、atory.This provides information concerning call attempt or call establishment. For details of the parameters, see 4.3.2 d);e) time of delivery optional.This is the time at which the CF delivered the partial telex message to the telex terminal if a partial deliverywas achieved;f) telex transmission d
38、uration - optional.This may be provided if a partial delivery was achieved;g) last page delivered - optional.This shall identify the last page number, and its document reference number, successfully transmitted totelex;h) failure cause - mandatory.The cause may be one of the following examples: serv
39、ice signal from telex network; clearing before call connect; wrong answerback; clear or break during message transmission; submitted normal document not in the telex mode;Fascicle VII.5 - Rec. T.390 7i) note optional see 4.3.2 g);j) received recorded message optional see 4.3.2 h).4.5 Telex validatio
40、n control document4.5.1 The telex validation control document is used by the CF to indicate to the called Teletex terminal that amessage from telex will subsequently be sent from the CF. The use of this control document is a national matter (e.g.for unique message identification) and shall not be al
41、lowed over international connections.4.5.2 Elements of the control text are:a) control document identifier - mandatory;b) reference - mandatory. This reference is assigned by the CF.4.6 Telex message delivery control document4.6.1 The telex message delivery control document is used by the CF to indi
42、cate to the Teletex terminal that theassociated subsequent normal document was received from a telex terminal. The use of this control document is anational matter.Note The use of this control document over international connections requires further study.4.6.2 Elements of the control text are:a) co
43、ntrol document identifier mandatory;b) reference optional.This reference is assigned by the CF. If the telex validation control document is used, then this referencemust be quoted;c) received time mandatory.This contains the time at which the telex was received by the CF;d) received telex answerback
44、 optional.This is the complete telex answerback as received by the CF;e) Note optional see 4.3.2 g).5 General rules for control documents5.1 Control document utilizationTeletex terminals shall be capable of constructing messages, each consisting of a control document linked witha sequence of normal
45、documents. The message ends at either the start of the next control document, or at the normalend of the session.5.1.1 The Teletex terminal will allow the following types of communication to a CF within a single session: one or more normal documents covered by the same control document (“normal” doc
46、uments shall be in the“telex” mode); one or more addresses covered by the same control document. The provision of this capability in a CF is anational matter; more than one control document and related normal documents in the same session. The provision of thiscapability in a CF is a national matter
47、.5.1.2 When interworking with telex, the following rules shall apply (see Figure 3/T.390): a control document relates to the normal documents which follow it, up to the next control document (ifany) within the session, or up to the normal end of the session; the presence of more than one address in
48、a control document indicates multi-addressing of all relatednormal documents; within a session, document reference numbers will be assigned, as specified in Recommendation T.62,without distinction between control documents and normal documents.8 Fascicle VII.5 - Rec. T.3906 Error recovery in Teletex
49、/telex interworking6.1 Message transfer from Teletex to telex6.1.1 During a session, the CF shall perform automatic linking using the procedures specified in T.62.6.1.2 In the case where a session interruption or CF memory overflow occurs, the following shall apply:a) All complete messages received and positively acknowledged in that session shall be handled by the CF asin error-free operation.b) The CF shall handle the interrupted message in one of