1、CEPT T/GSI*02-03 E 2326434 O005397 O W (3 02-03 Page 1 E Recommendation T/GSI 02-03 (Nice 1985, revised by correspondence, June 1987) TELESERVICES Recommendation proposed by the Special Group Integration (GSI) Text of the Recommendation adopted by the “Telecommunications” Commission: “The European C
2、onference of Posts and Telecommunications Administrations, considering - the common CEPT approach to the ISDN and general CEPT assumptions and policies for the evolution towards - the I. Series Recommendations of the CCITT, as well as other CCITT Recommendations on ISDN, to which - the need for CEPT
3、 Administrations to have as a base a comprehensive set of Recommendations, in order to ISDN, CEPT Administrations have contributed most significantly, promote and strengthen European harmonisation, O recommends to the member Administrations of the CEPT that they evolve their telecommunication networ
4、ks towards ISDN according to the following specifications. The CEPT Administrations recommend that European Administrations wishing to provide ISDN services apply the Teleservice definitions according to this Recommendation which represents the present status of the work. The following Teleservices,
5、 as listed Recommendation T/SF 3 1, should be made internationally available on the ISDN: - Telephony; - Teletex; - Facsimile; - Videotex; - Message handling (Note); - Audiconference (Note).” Note. The definition of this teleservice is under study. Edition of October 31, 1987 3 CEPT T/GSI*02-03 E I
6、W 232b414 0005398 2 TIGSI 02-03 E Page 2 The purpose of this Recommendation is to provide an outline and allocation of attributes of teleservices to be used as a basis for defining the network capabilities required by an ISDN and to give a framework for the standardization of teleservices for guidan
7、ce to other Study Groups (Le. definition of values associated with the attributes). 1. FRAMEWORK FOR DESCRIBING TELESERVICES SUPPORTED BY AN ISDN Teleservices supported by an ISDN are described by a number of attributes which are intended to be largely independent. They are grouped into three catego
8、ries: - Low layer attributes - information transfer at tributes; - access attributes. - High layer attributes. - General attributes. Note. Teleservices generally make use of underlying lower layer capabilities of bearer services specified in Recommenda- tion T/GSI 02-02. However, where teleservices
9、are provided by a single Administration RPOA or other services provider, the combination of values of lower attributes applicable to specific teleservices may not necessarily be identical to any of those identified for the bearer services appearing in Recommendation T/GSI 02-02. Figure 1 (T/GSI 02-0
10、3) shows the relationship between the different categories of service attributes, and their scope within a teleservice. Information transfer attributes SIT r-+l SIT - - - - - - - - - - - - - - - Access point 3or 5 as General defined in attributes Recommen- dation Access point 3or 5 as defined in Rem
11、mmen- dation ISDN including HLF if necessary L _ J T/GSI 02-02 TIGSI 02-02 Access Access attributes attributes Hiah laver attributes 2. 2.1 Figure 1 (T/GSI 02-03). Relationship between the categories of service attributes and their scope within a Teleservice. LIST OF THE TELESERVICE ATTRIBUTES The d
12、escription of the teleservices is based upon the list of attributes as given in Figure 2 (T/GSI 02-03). The type of user information is called Dominant attribute and is used to identify a particular Teleservice category. High layer attributes are called secondary attributes and are used to identify
13、individual Teleservi- ces within one category. Low layer attributes and general attributes are called qualifying attributes and are used to further specify on individual Teleservices. It is intended that individual teleservices belonging to the same category shall be able to interwork. In addition s
14、ome networks may provide arrangements in order to allow interworking between some teleservi- ces belonging to different categories. Low layer attributes (see Recommendation T/GSI 02-02) Qualifying attributes - information transfer attributes - access attributes O Edition of October 31, 1987 CEPT T/G
15、SI*02-03 E 1 D 2326434 0005399 4 D TIGSI 02-03 E Page 3 2.2. High layer attributes - Type of user information; 7 Dominant attribute (Note 3) - Gier 4 protocol functions; - Layer 5 protocol functions; - Layer 6 protocol functions: where qualifying attributes applicable (Note I) where 1 (Note 2) 1 - R
16、esolution Graphic mode - Layer 7 protocol functions: - TE-to-HLF protocol functions applicable - TE-to-TE protocol functions Secondary attributes (Note 3) Note 1. Attributes are mentioned in order to give an example of a specific presentation description of characteristics such as coding of the user
17、 information, resolution and graphic mode. Attributes for other presentation characteristics are for further study. Note 2. Attributes are shown in order to give an example of a description of a teleservice application involving two terminals at both access points (30245) and an intervening system p
18、roviding HLF functions (see Figure 3c and Figure 3e in Recommendation T/GSI 02-01). A specific teleservice attribute description for this case is for further study. Note 3. The borderline between dominant attributes and secondary attributes requires further consideration. 2.3. General attributes O Q
19、ualifying attributes 1 Supplementary low and high layer attributes (supplementary services); - user-oriented quality of services; - interworking possibilities; - operational and commercial. Figure 2 (T/GSI 02-03) presents a list of possible values for each service attribute. Where optional values of
20、 given attributes are offered, their selection is subject to agreement between the customer and service provider. Edition of October 31, 1987 CEPT T/GSI*02-03 E I Possible values of attributes TIOSI 02-03 E Page 4 Service attributes 232bYl14 0005400 7 T/GSI 04-02/1 Others FS 9.1 Signalling access pr
21、otocol layer 1 Refer to Recommendation T/GSI 02-02 Others FS Information transfer and access attributes 9.2 Signalling access protocol layer 2 X.25 Others FS G.711 Others FS I I I 9.3 Signalling access protocol 9.4 Information access proto- layer 3 col layer 1 46-30 04-0211 04-0211 46- 46- T.70 X.25
22、 Others FS 9.6 Information access proto- col layer 3 9.5 Information access proto- col layer 2 Sound Text Fac- simile Text Fac- Videotex Video Others 10. Type of user information simile X.224 X.225 I T.73 I G.711 I T.61 I T.6 I T.100 I Others I 13. Layer 6 protocol T.70 Others 11. Layer 4 protocol T
23、.62 Others 12. Layer 5 protocol 200 240 300 400 Others 13.1 Resolution (Note) Note. If applicable. Figure 2 (T/GSI 02-03). Possible values for attributes characterizing Teleservices. Alpha-mosaic 3. DESCRIPTION OF ISDN TELESERVICES This section contains attribute descriptions of teleservices (see No
24、te I). Descriptions for the teleservices telephony, teletex, telefax, mixed mode (telefax), Videotex and telex supported by ISDN are given. Descrip- tions for other teleservices may be added to this section. The service attributes listed in section 2 of Recommendation T/GSI 02-03 and in Table 1 of R
25、ecommenda- tion T/GSI 02-02 have been used to describe each teleservice. It should be noted, however, that the information transfer and access attribute values given in the descriptions are only a possible implementation in the ISDN. Implementations using alternative low layer attribute values, e.g.
26、 packet-mode, are permitted for the same teleservice. It would be desirable from a service interworking perspective that the low layer attributes for a particular teleservice implementation be the same as the bearer capabilities of the bearer services specified in Recom- mendation T/GSI 02-02. The l
27、ayer 4 to 7 protocol function and type of user information attribute values (i.e. attribute number 10 to 14) are the recommended implementation in ISDN. These high layer attributes may be considered the dominant attributes for teleservices. These attributes provide a means to differenciate teleservi
28、ces. Note 1. An additional dynamic description giving examples of operation of each teleservice at ISDN access points 3 or 5 (see Recommendation T/GSI 02-01) is under study. Geometric Photographic Others 13.2 Graphic mode (Note) O Xition of others: FS Operational and commercial aspects: FS 3.3. Facs
29、imile Teleservice Category 3.3.1. Telefax Supported by the ISDN (TFX) This service provides end-to-end facsimile communication using standardized picture coding, resolution, and communication protocols. The high layer attributes are based on the facsimile Group 4 Recommenda- tions of CCITT. User inf
30、ormation is provided via a B-channel, signalling via the D-channel. Attributeslvalues : (a) Low layer attributes Info transfer attributes 1. Mode: Circuit 2. Rate: 64 kbit/s 3. 4. 5. Establishment: Demand 6. Configuration: Point-to-point 7. Symmetry: Bidirectional symmetric Info transfer cap. : Unre
31、stricted Structure: 8 kHz integrity (Note) Note. Not requested by the service but inherent to the bearer capability. Access attributes 8. Access channel: B for user info, D for signalling 9.1 Signalling a.p. layer i : T/GSI 04-02/1 9.2 Signalling a.p. layer 2: T/S 46-20 9.3 Signalling a.p. layer 3:
32、T/S 46-30 9.4 Information a.p. layer 1: T/GSI 04-02/1 9.5 Information a.p. layer 2: HDLC-LAP B (X.75) 9.6 Information a.p. layer 3: T.70 O Edition of October 31, 1987 CEPT T/GSI*02-03 E W 232b4L4 0005403 2 T/GSI 02-03 E Page 7 (b) High layer attributes 10. 11. Layer 4 protocol: T.70 12. Layer 5 prot
33、ocol: T.62 13. Layer 6 protocol: T.73-TIF.0, T.6 13.1 Resolution (ppi): 200 x 200 standard; 14. Layer 7 protocol: T.5-C1.l 15. Supplementary attributes: FS 16. 17. 18. Type of user info: Facsimile 240 x 240, 300 x 300, 400 x 400 optional (c) General attributes User-oriented quality of service: FS In
34、terworking possibilities: ISDN Textfax; see Appendix 1 ; others: FS Operational and commercial aspects: FS 3.4. 3.4.1. Text or facsimile teleservice category Mixed Mode Supported by the ISDN (MXM) This service provides combined text and facsimile communication (mixed mode) for end-to-end transfer of
35、 documents containing mixed information of text and fixed images. The high layer attributes are based on the CCITT Recommendations for the Teletex service and facsimile Group 4, mixed mode (F.200, Annex C). User information transfer is provided via a B-channel, signalling via the D-channel. A ttribu
36、tes/values : (a) Low layer attributes Info transfer attributes 1. Mode: Circuit 2. Rate: 64 kbit/s 3. 4. 5. Establishment: Demand 6. Configuration : Point-to-point 7. Symmetry: Bidirectional symmetric O Info transfer cap. : Unrestricted Structure: 8 kHz integrity (Note) Note. Not requested by the se
37、rvice but inherent to the bearer capability. Access attributes 8. Access channel: B for user info, D for signalling 9.1 Signalling a.p. layer 1 : T/GSI 04-02/1 9.2 Signalling a.p. layer 2: T/S 46-20 9.3 Signalling a.p. layer 3: T/S 46-30 9.4 Information a.p. layer 1 : T/GSI 04-02/1 9.5 Information a
38、.p. layer 2: LAP B (X.75) 9.6 Information a.p. layer 3: T.70 (b) High layer attributes 10. Type of user info: Text a 1 1. Layer 4 protocol: T.70 12. Layer 5 protocol: T.62 13.1 Resolution (ppi) : - 13. Layer 6 protocol: T.73-TIF.1, T.61 14. Layer 7 protocol: T.72 d facsimile T.70 T.62 200x200, 300x3
39、00 240 x 240 (receiving) standard; 240x240,400x400 optional T.72 T.73-TIF.l, T.6 (c) General attributes 15. Supplementary attributes: FS 16. 17. 18. User-oriented quality of service: FS Interworking possibilities : ISDN Teletex, ISDN Facsimile Service; others: FS Operational and commercial aspects:
40、FS Edition of October 31, 1987 I CEPT T/GSI*02-03 E 232b414 0005404 4 8 kHz integrity Demand Point-to-point T/GSI 02-03 E Page 8 8 kHz integrity (Note)/ Service data unit integrity Demand/permanen t Point-to-point/multipoint 3.5. Videotex Teleservice Category 3.5.1. Videotex Supported by the ISDN (V
41、DX) The Videotex service in the ISDN is an enhancement of the existing Videotex service with retrieval and mailbox functions for text (alpha) and graphic (mosaic, geometric, photographic) information. Attributes/ Values: (a) Low Layer Attributes Info transfer attributes 10. Type of user info: Text (
42、alpha) graphic type 1 i. Mode: 2. Rate: 3. Info transfer cap.: 4. Structure: Graphic Graphic type 2 type 3 5. Establishment: 6. Configuration: 7. Symmetry: 13. Layer 6 protocol: T.73-TIF. 1, T. 10 13.1 Resolution (ppi) See T.lO1 13.2 Graphic mode: Mosaic I Eometric FS Photographic Edition ofOctober
43、31,1987 CEPT T/GSI*02-03 E W 2326414 0005405 b T/GSI 02-03 E Annex 1, page 9 Annex 1 List of Mnemonics for teleservices TPH TTX TFX VDX MXM ADX AGC TLC EFT TLX MHSS Telephony* Teletex* Telefax* Videotex* Mixed-Mode* Audiovideographic Audiographic Teleconference Electronic Fund Transfer Telex Message
44、 Handling System Service * Teleservices currently specified in this Recommendation. The others require further study. Edition of October 31, 1987 - CEPT T/GSI*02-03 E 2326434 O05llOb B TIGSI 02-03 E Appendix 1, page 1 O Appendix 1 (for information and further study is required) Description of telese
45、nice interworking possibilities This section provides an initial description of the interworking possibilities for ISDN teleservices with similar existing services supported on dedicated networks, .e. PSTN, telex, CSPDN, and PSPDN. In the following, a first draft of teleservice interworking descript
46、ions for the teiefax and telephony teleservices is given. For the time being, these descriptions should be considered as a starting point of the study of teleservice interworking possibilities. Contribu- tions are solicited for additional descriptions. 1. TELEFAX TELESERVICE INTERWORKING 1.1. Prose
47、description of interworking possibilities The telefax service in ISDN will have interworking with the telefax service in other networks such as PSTN, PSPDN and CSPDN. Three main cases are distinguished, namely: i) Interworking between telefax group 4 (with group 312 capabilities) in ISDN and telefax
48、 group 312 in PSTN or ISDN. i) Interworking between telefax group 312 in ISDN and telefax group 312 in PSTN. iii) Interworking between telefax group 4 in ISDN and teiefax group 4 in PSTN, PSPDN or CSPDN. The interworking between telefax group 312 terminals in PSTN and telefax group 4 terminals in no
49、n ISDNs is the subject of other Recommendations. Interworking between telefax group 4 (with group 312 capabilities) in ISDN and telefax group 312 in PSTN (case i) - Case i) is regarded as a subset of case i) and will not be dealt with explicitely in the following text. - The service obtained when the communication is involving interworking between a telefax group 4 terminal (with group 312 capabilities) in ISDN and a telefax group 312 terminal in ISDN or PSTN is based on parameters and procedures for telefax group 312. Outgoing call (ISDN to PSTN) A notific
