1、INTERNATIONAL TELECOMMUNICATION UNION)45G134 (b) that the F-series of Recommendations describe the operations and quality of Telematic services;(c) that many countries wish to adopt a common strategy for introducing the non-voice Telematic services onISDN;(d) that there is a need to harmonize the se
2、rvice approach for Telematic services, specially the requirements forsupplementary services;(e) that intercommunication is required between the existing non- voice services on the dedicated networks andnon-voice services in the ISDN;(f) that there is a need to identify the priority for introducing n
3、on-voice Telematic services in the ISDN,recommendsthat the guidelines laid down in this Recommendation be followed in providing Telematic and datatransmission services on ISDN.1 Existing services provided on ISDNWhen Telematic and data services are provided on ISDN, it is necessary to refer to the R
4、ecommendation ofeach service for service description:F.160 General operational provisions for the international facsimile servicesF.162 Operational requirements of an international store-and-forward facsimile switching service(COMFAX)F.170 Operational provisions for the international public facsimil
5、e service between public bureaux(bureaufax)F.180 General operational provisions for the international public facsimile service between subscribersstationsF.184 Operational provisions for the international public facsimile service between subscribers stations withGroup 4 facsimile machines (Telefax 4
6、) (formerly Recommendation F.161)F.190 Operational provisions for the international facsimile service between public bureaux and subscriberstation and vice versa (Bureaufax-Telefax and vice versa)F.200 Teletex serviceF.201 Interworking between the Teletex service and the telex service General princi
7、plesF.202 Interworking between the telex service and the Teletex service General procedures and operationalrequirements for the international interconnection of telex/Teletex conversion facilities.F.203 Network based storage for the Teletex serviceF.220 Service requirements unique to the processable
8、 mode number one (PM1) used within the TeletexserviceF.230 Service requirements unique to the mixed mode (MM) used within the Teletex serviceF.300 Videotex service2 Fascicle II.5 - Rec. F.353F.400 Message Handling System and Service overviewF.500 International public directory servicesExisting servi
9、ces that may be provided on ISDN have to intercommunicate with the same services on existingnetworks including existing conversion facilities (see Table 1/F.353).TABLE 1/F.353ISDN Integrated Services Digital NetworkPSTN Public Switched Telephone NetworkCSPDN Circuit Switched Public Data NetworkPSPDN
10、 Packet Switched Public Data NetworkMHSS Message Handling System ServicesNote 1 Telex on the ISDNNote 2 The migration form non-ISDN terminals to ISDN is a national matter.Note 3 If existing terminals migrate to ISDN, their compatibility with terminals on existing networks shallnot be degraded.Note 4
11、 Compatibility between ISDN terminals and existing terminals must be retained.Where administrations offer the telex service on the ISDN, the following principles should be followed:i) Operational procedures should be in accordance with Recommendation F.60.ii) The telex terminal on the ISDN should be
12、 addressable, from international telex networks, by the F.69 telexdestination code and a national telex number. The maximum length of the national telex number should bein accordance with the telex signalling requirements of the CCITT U-series of Recommendations.2 New services1)provided on ISDNNew s
13、ervices that may be provided on ISDN with intercommunication requirements with other services onISDN and on existing networks (see Table 2/F.353)._1)A new service is one that is not yet generally available on existing networks.Existing services on ISDN Services on existing networkTeletexTelex (see N
14、ote 1)Telefax 2/3VideotexMHS servicesData transmissionTeletex (PSTN, CSPDN, PSPDN)TelexTelexTeletex (PSTN, CSPDN, PSPDN)Telefax 2/3 (PSTN)Videotex (PSTN, PSPDN)MHS S (PSTN, CSPDN, PSPDN)Data transmission(PSTN, CSPDN, PSPDN)Fascicle II.5 - Rec. F.353 33 Teleservices classification3.1 General principl
15、esTeleservices classification allows structured approach of the compatibility problem between terminals of theTelematic services.To ensure stability of the classification in the future, the list has been divided into major categories.Each category contains a limited representative set of ISDN telese
16、rvices. The subsequent development of thislist will take into account the new Telematic services which could be defined by the CCITT.TABLE 2/F.353Note 1 Videotex service using the full capacity of the 64 kbit/s B-channel of the ISDN access.Note 2 Additional intercommunication requirements may be ide
17、ntified subsequently.A Telematic service is defined by its specific operational rules, by the list of supported standardizedfunctionalities (applications or modes) and by the relevant communication protocols.Each application or mode handles presentation schemes based on the user of one medium or sev
18、eral mediawhich can by synchronized. A medium conveys the characteristics of information presented to the user.The simplest and the most discriminant form of classification has to consider the media as the basic elementsbased upon which the categories are elaborated.3.2 Teleservices listThe followin
19、g list will be completed progressively taking into account the new services as they will appear inthe next years.Audio services Telephony Audio conference . . . (other audio service)New services on ISDNServices on ISDN andexisting networksTeletex with mixed modeTeletex with processable mode (PM1)Tel
20、efax 4 Class ITelefax 4 Class IITelefax 4 Class IIIVideotex 64(see Note 1)Teletex (PSTN, CSPDN, PSPDN, ISDN)Telefax 4 (ISDN, CSPON)TelexTeletex (PSTN, CSPDN, PSPDN, ISDN)Telefax 4 (ISDN, CSPDN)(Class II, III)TelexTelefax 3 (PSTN)Telefax 4 (CSPDN)Telefax 3 (PSTN)Telefax 4 (CSPDN)Teletex (PSTN, CSPDN,
21、 PSPDN, ISDN)Telefax 3Telefax 4Teletex (PSTN, CSPDN, PSPDN, ISDN)Videotex (PSTN, PSPDN, ISDN)4 Fascicle II.5 - Rec. F.353Text and data services Telex Teletex Telefax 3 Telefax 4 Videotex Telewriting Data transmission MHS . . . (other text and data service)Video services (see Note) Videophone Video c
22、onference . . . (other video service)Multimedia services Audiovideography Audiography Telematic audio conference Telematic video conference Teleaction . . . (other multimedia service)Note In this category, the sound is always and implicitly included.4 Interworking requirements4.1 GeneralInterworking
23、 of Telematic terminals with compatible terminals on ISDN is mandatory.In order to maintain the defined quality of service, suitable selection mechanisms have to be implemented toguarantee access to compatible terminal.4.2 Interworking with the Teletex serviceInterworking between all terminals conne
24、cted to different networks must be possible.Real-time connection between Teletex terminals operating at different speeds is required for the duration of thecall. The information on the successful transmission should be given by the receiving terminal to the sending terminalwithin the call.The proced
25、ures for call set-up to terminals connected to different networks should be as similar as possible.Interworking with international telex is mandatory.4.3 Interworking within the Telefax 4 serviceInterworking between all terminals connected to different types of networks must be possible.Real-time co
26、nnection between Telefax 4 terminals operating at different speeds is required for the duration ofthe call. The information on the successful transmission should be given by the receiving terminal to the sendingterminal within the call.The procedures for call set-up to terminals connected to differe
27、nt networks should be as similar as possible.Fascicle II.5 - Rec. F.353 54.4 Interworking from Telefax 4 to Telefax 3Interworking between Telefax 4 terminals and Telefax 3 terminals should be possible even if they areconnected to different types of networks. The preferred method of interworking is t
28、o be provided by the inclusion of aGroup 3 capability in the Group 4 terminal.Real-time connection between Telefax terminals (Group 3 and Group 4) operating at different speeds isrequired for the duration of the call. The information on the successful transmission should be given by the receivingter
29、minal to the sending terminal within the call. Interworking between Group 4 only terminals and Group 3 terminalscould be resolved by using network units (store-and-forward or MH system). Further study on this is needed.The procedure for call set-up to terminals connected to different networks shall
30、be as similar as possible.4.5 Additional interworking configurationsOther interworking configurations are for further study.5 Assignment of prioritiesThe current assignment of priorities to the future work is:a) Priority for non-voice teleservices:1) existing Telematic services on ISDN,2) new non-vo
31、ice Teleservices.b) Priority for bearer services:1) new bearer services on ISDN,2) use of bearer services of ISDN by existing terminals.6 Introductional strategy guidelineThese are strategic guidelines for the introduction of existing services on ISDN. The implementation is strictlya national matter
32、; however, a measure of co-ordination is necessary internationally in order to provide users worldwideattractive telecommunication services, appropriate intercommunication possibilities, and thereby to ensure financialsuccess for the service providers.Any existing service introduced on ISDN should h
33、ave immediate access to the same service on existingnetworks.There should be minimum changes in the user access procedures.Any transition from existing to future international tariffs and accounting should be orderly.The suggested provisional list of priorities for the implementation of existing ser
34、vices on ISDN is:1) Teletex, Telefax, Videotex;2) Data transmission;3) Message Handling System Services;4) Telex.It is stressed once again that the priority of implementation is a national matter but it has significantinternational relevance.Simultaneous implementation of existing services on ISDN i
35、n all countries is deemed desirable and effortsshould be made to achieve this goal.7 Bearer services for non-voice communicationsRecommendation I.211 describes and defines a recommended set of bearer services and their bearer capabilitiesto be supported by an ISDN as a basis for defining the network
36、 capabilities required.The purpose of this chapter is to indicate the recommended bearer services associated to non-voice Telematicteleservices:6 Fascicle II.5 - Rec. F.3537.1 Circuit mode bearer services 64 kbit/s unrestricted, 64 kbit/s (usable for speech information transfer), 64 kbit/s (usable f
37、or 3.1 kHz audio information transfer), 384 kbit/s unrestricted, 1536 kbit/s unrestricted, 1920 kbit/s unrestricted,2 64 kbit/s unrestricted.7.2 Packet-mode bearer services Virtual call and permanent virtual circuit (B or D channel); Connectionless packet bearer service on a D channel (further study needed); Use signalling bearer service on a D channel (further study needed).
