CEPT T CAC S 10 3 E-1992 Teleservices to Be Provided by an Integrated Services Digital Network (ISDN)《要由综合业务数字网(ISDN)提供的电信业务》.pdf

1、CEPT T/CAC*S*LO-3 E 92 2326434 0013569 066 CEPT Telecom T/CAC S 10.3 E Page 1 Recommendation T/CAC S 10.3 E (Vienna 1989 (CAC) and Athens 1992) Formerly Recommendation T/SF 31 -03 E TELESERVICES TO BE PROVIDED BY AN INTEGRATED SERVICES DIGITAL NETWORK (ISDN) Recommendation proposed by Working Group

2、T/GT 7 “Services and Facilities” (SF) Amendments proposed by Project Team Service Descriptions for the ISDN (SDI) Text of the Recommendation adopted by Commercial Action Committee (CAC) CONTENTS 1. General 2. List of Teleservices 3. Definitions of Teleservices Annex 1 : Telephony 3.1 kHz Annex 2: Te

3、lephony Service 7 kHz Annex 3: Teletex Annex 4: Telefax Group 4 Annex 5: Mixed Mode Annex 6: Videotex Annex 7: Telex Annex 8: Videotelephony Edition of November 20. 1992 TICAC S 10.3 E Page 2 1. 2. 3. 3.1. 3.2. CEPT T/CAC*S*l0*3 E 92 2326414 OOSS570 CI overall requirements are given in the P-Series

4、of CCIlT Recommendations. Transmission Delay: The maximum delay is that specified for the general telephone network (cf. CCITT Recommendation G.114). Retention Time: This time specifies the amount of time during which the network retains the call information of the original call upon encountering bu

5、sy or being released. This time is a network operator Edition of November 20, 1992 TICAC S 10.3 E Annex 1. Page 2 CEPT T/CAC*S*50*3 E 92 M 23Zblilli 0055573 597 W CEPT Telecom TELEPHONY 3.1 KHZ option. The value for this time is greater than 15 seconds. 3. PROCEDURES 3.1. Provision and Withdrawal Pr

6、ovision of this service will be by arrangement with the network operator. This Teleservice is offered with several subscription options which apply separately to each ISDN number or groups of ISDN numbers on the interface. For each subscription option, only one value can be selected. Subscription op

7、tion for the interface are summarised below: Subscription Optfon Value Maximum number of information channels available at user B m, where m is not greater than the number of information channels on the interface Maximum number of total calls pres- ent at user B User B can be an ISDN number or a gro

8、up of ISDN numbers on the interface. n, where n is not greater than the number of information channels on the interface Note: More than one ISDN number can be accociaied with the serviWinterface only as pari of a supplementary service such as the Multiple Subscriber Number. In the case of one ISDN n

9、umber, the option given above for the number of calls can only exceed the number o information channels in ascociation with a supplementary service (e.g. Gail Waiting). As a new G.71 I CCITT Recs 1.440/1.441 - CCITT Recs 1.450/1.4!51 - For reserved permanent service the operational, adminiclrative,

10、and maintenance meccages related to these services may be conveyed over the D-channei. Hlgh Layer Attributes Type of user information Layer 4 protocol functions Layer 5 protocol functions Layer 6 protocol functions Layer 7 protocol functions Speech CCITT Rec. G.711 - - General Attributes Supplementa

11、ry services Quality of service Interworking possibilities Operational and commercial aspects See Recs. T/CAC S 10.5 to 10.7 and CC17T Rec. T.250 See Rec. T/CAC S 10.4 See CEPT: User Handbook, ISDN - = Not Applicable. Edition of November 20. 1992 CEPT Telecom TJCAC S 10.3 E Annex 1. Page 5 TELEPHONY

12、3.1 KHZ 8. DYNAMIC DESCRIPTION The circuit-mode dynamic description appears in CCITT Recommendation 1.220 Edition of November 20. 1992 CEPT T/CAC*S*L0=3 E 92 m 2326434 0031577 132 m CEPT Telecom TICAC S 10.3 E Annex 2. Page 1 TELEPHONY 7 KHZ Annex 2 TELEPHONY 7 KHZ 1. DEFINITION The Telephony 7 kHz

13、teleservice provides users with the ability for real time two-way high quality speech conversation via the network. 2. DESCRIPTION The Telephone 7 kHz service provides, via the network, the ability to transfer high quality speech allowing users to communicate by interchanging sounds with a high qual

14、ity. The communication is bidirectional with both directions continuously and simultaneously active during the speech phase. This service provides high quality speech communication with a frequency range of 50 to 7000 Hz. The digital signal at the S/T reference point follows the internationally agre

15、ed encoding laws for high quality speech (CCITT Recommendation G.722). User information is provided over a B-channel, signalling is provided over the Dchannel. Tones and announcements are provided by the network. Terminals can, however, generate tones or other indications based on the messages recei

16、ved. 3. OPERATIONAL REQUIREMENTS 3.1. Normal Procedures 3.1 .l. Originating the Service (Cali Setup) The service is originated by the originating user activating the terminal, performing service selection, if applicable for the originating terminal, and terminating customer selection. During the cal

17、l setup stage the originating user is given the appropriate indications as to the state of the call. 1) Service selection is required on multi-sewice terminals and may consist of directly selecting the Telephony 7 kHz teleservice. 2) Terminating customer selection is selecting the required terminati

18、on (user/network interface) by means of the appropriate network number. In association with Telephony 7 kHz a specific terminal on that interface may be selected by the use of e.g. Direct Dialling In or Sub-Addressing. Edition of November 20. 1992 T/CAC S 10.3 E Annex 2. Page 2 CEPT Telecom TELEPHON

19、Y 7 KHZ 3) Indications during call origination may include an indication that the network is ready to receive the network address information (proceed indication) and an indication that the call is progressing through the network. It shall be audible indications but may also be accompanied by other

20、indications. 3.1.2. Call Acceptance (Answer) Selection of the terminating customer is indicated to each user by appropriate indications (call arrival indication and awaiting answer indication). The acceptance of the call by the ter- minating user (answer) causes the indications to be removed and bid

21、irectional communica- tion paths to be provided. The call is now termed in the speech phase. 3.1.3. Terminating the Service (Call Release) A request to terminate the service may be generated by either user. If one user terminates the service the other user is given an appropnate indication as to the

22、 state of the call, pro- vided the call has entered the speech phase. 3.2. User Requirements In case of Unsuccessful Outcome 3.2.1. Failure Situations due to User Error The following failure situations may occur due user error: 1) User taking too long to input the network number information will be

23、given a failure indication where overlap sending applies (see CCITT Recommendation 1.451). 2) User inputting a non-valid network number, e.g. an unallocated number, will be given a failure indication. 3.2.2. Failure Situations due to Terminating Termination State 1) User attempting to set up a call

24、to termination where no free B-channel is available will receive a busy indication unless Call Waiting or another supplementary service is in operation. 2) User attempting to set up a call to termination where the call is not accepted, .e. I#) response indication call acceptance is received will aft

25、er a defined period be given a call failure indication (see CCITT Recommendation 1.451). 3.2.3. Failure Situations due to Network Conditions User attempting to set up a call meeting problems in the network (e.g. congestion) will be given a suitable indication. 4. CHARGING REQUIREMENTS It shall be po

26、ssible to charge for the service on a per call basis, based on duration of the call, the numbers of the called and calling parties, and the time of day. Other parameters for use in charging determination may also be available. Edition of November 20, 1992 CEPT T/CAC*S*LU.3 E 72 W 2326414 0011577 TU5

27、 CEPT Telecom TELEPHONY 7 KHZ T/CAC S 10.3 E Annex 2. Page 3 5. INTERCOMMUNICATION CONSIDERATIONS When communication is required with either ISDN telephony terminal incapable of 7 kHz working, or to and from the PSTN, the following applies. 5.1. Non 7 kHz ISDN Terminals As the calling customer will

28、not necessarily know the capability of the called customers terminals, it shall be possible for a calling customer to set up a call from his telephony 7 kHz terminal by requesting Telephony 7 kHz. In such situations, where the incoming call is answered by a non 7 kHz telephone, this service will aut

29、omatically defauk to the telephony mode and provide communication accordingly. 5.2. Interworking with the PSTN Where a telephony 7 kHz call setup is attempted to a customer on the PSTN, the calling customer will be given an appropriate indication that interworking with the PSTN has occurred, but the

30、 network will continue call setup. If the calling customer does not abandon this call attempt, then this service will automatically default to the telephony mode and provide communication accordingly 6. INTERACTION WITH SUPPLEMENTARY SERVICES Each supplementary service description identifies the app

31、licability to this teleservice. If the in-band communication is interrupted by the network as a result of one user invoking a supplementary service (e.g. the Call Hold supplementary service or the Terminal Portability supplementary service) then the network shall provide an appropriate indication in

32、 the B- channel. 7. ATTRIBUTES AND VALUES Attributes a) Low Layer Attributes Information transfer attributes: 1. Information transfer mode 2. Information transfer rate 3. Information transfer capability 4. Structure 5. Establishment of communication 6. Communication configuration 7. Symmetry Access

33、atribufes: 8. Access channel (and rate) Edition of November 20. 1992 Values Circuit 64 kbit/s Unrestricted digital information 8 kHz integrity On demand Point-to-point Bidirectional symmetric B(64) for user information and for signal- ling VCAC S 10.3 E Annex 2. Page 4 CEPT T/CAC*S*L0*3 E 92 W 232b4

34、L4 OOLL580 727 H CEPT Telecom TELEPHONY 7 KHZ 9. Signalling access protocol b) High Layer Attributes 10. Type of user information 11. Layer 4 protocol functions 12. Layer 5 protocol functions 13. Layer 6 protocol functions 14. Layer 7 protocol functions c) General Attributes 15. Supplementary low la

35、yer and high attributes (supplementary services 16. Quality of service 17. Inteworking possibilities 18. Operational and commercial aspects Note: - = Not applicable. 7 kHz Speech CCITT Rec. G.722 - See CEPT Rem TCAC S 10.5 to 10.7 and CCITT Rec. 1.250 See Rec. T/CAC S 10.4 See CEPT: User Handbook, I

36、SDN Edition ai November 20, 1992 CEPT T/CAC*S*LO-3 E 92 m 2326434 003L.583 663 m CEPT Telecom TELETEX T/CAC S 10.3 E Annex 3. Page 1 1. 2. Annex 3 TELETEX DEFINITION Teletex is an international service enabling subscribers to exchange off ice correspondence in the form of documents containing telete

37、x coded information on automatic memory-to- memory basis via the ISDN. DESCRIPTION The Teletex service provides communication between teletex equipments which are used for the preparation, editing, and printing of correspondence containing text information using a standardised character set (Recomme

38、ndation T.61). The basic element of correspondence between people using the service is the page as the smallest unit of text treated as an entity. No restrictions shall exist as far as the operator procedures for generation of the text or the positioning of text within the printable area on a page a

39、re concerned. Note 1: This does not necessarily imply that the characters used to consiruct a graphical symbol are bansmitted in the same sequence as that in which they are keyed. Note 2: This does not necessarily imply that the order in which text on a page is transmitted is the same as that in whi

40、ch it was keyed. Note 3: An exception to this rule is the application of the processable mode of operation for which the page as a basic element of correspondence cannot be used. The procesable mode of Operation within the Teletex service is defined in CCIlT Recommendation F.220. The Teletex service

41、 in each country and the international interconnection between countries of networks shall use automatic switching so that it is possible for any telex subscriber to reach any other teletex subscriber using fully automatic selection. It is a requirement to allow the through-connection of a call betw

42、een a teletex terminal connected to a private automatic branch exchange (or similar systems) and those connected to public exchanges used for the Teletex service. A virtual dialogue mode of operation, which appears to the subscriber as a conversational mode, should be possible atthough this is not a

43、 basic requirement of the Teletex service. A virtual dialogue of operation, which appears to the subscriber as a conversational mode, may become possible as a new standardised option within the Teletex service both allowing communications between persons and data base access (refer to CCITT Recommen

44、dation 1.210). Edition of November 20, 1992 TICAC S 10.3 E Annex 3. Page 2 CEPT T/CAC*S*I,0.3 E 92 W 2326434 OOi155B2 5TT CEPT Telecom TELETEX Processable mode of operation, as a standardised option within the Teletex service, allows the transfer of text containing information for further editing an

45、d processing by the recipient (refer to CCITT Recommendation F.220). Mixed mode of operation using the techniques of Telefax 4 for the transfer of facsimile coded information and of Teletex for transfer of character coded text is described as a standardised option within the Teletex service in CCIIT

46、 Recornmendation F.220. Two-way Alternate (TWA) communication is a capability of the Teletex service, which also include One-way Communication (OWC); the calling subscriber will have full control of the teletex call. 3. PROCEDURES 3.1. Provision and Withdrawal The national and international faciliti

47、es of the Teletex service, including the TeletexTTelex conversion facilities, shall be open continuousiy. Teletex subscriber equipmentc for which call numbers are published in the directories shall, in principle, be available to accept calls continuously. in order to facilitate the 24 hours duration

48、 of the service it is permitted to use a centralised storage in the network to realice receiving memory capability of the terminal. 3.2. Call Phases The operation for each call may be divided into the following three phases: a) Preparation - Preparation of the information in local mode; - Loading of

49、 the information into a memory. b) Transmission (in principle, automatic) - Call establishment: - Pre-information phase (see Note); - Information transfer from memory to memory (see Note): - Post-information phace (see Note); - Call clearing. Note: During these parts of the transmission phace, the neiwork must be transparent with respect to control procedum. c) output - Emptying the memory. Note: The information may consist of one or more teletex documents, each consisting of one or mom teletex Pages. The control procedures as specified in CCITT Recommendation T.62 shall be used as the