1、:NEELN TELECOMMUNICATION STANDARD FINAL DRAR prl-ETS 300 043 March 1991 UDC: 621.396.21 Key words: Groupe Spcial Mobile (GSM) European digital cellular telecommunications system (phase 1); Terminal adaptation functions for services using synchronous bearer capabilities (GSM 07.03) ETSI European Tele
2、communications Standards Institute ETSI Secretariat: B.P.152 F - 06561 Valbonne Cedex . France TP. + 33 92 94 42 O0 TF. + 33 83 65 47 16 Tx. 47 O0 40 F I 11 !Jl,q 1 “ .rn -I - European Telecommunications Standards Institute 1991. All rights reserved. No part may be reproduced or used except as autho
3、rised by contract or .other written permission.-Th- Fyright and the foregoing restriction on reproduction and use extend to all media in which the 7 waytion may be embodied. -AL - - 9 3404583 00L7b78 O 9 -2- -. Whilst every care has been taken in.the preparation and publication of this document, err
4、ors in .,xmtentAypographical or otherwise, may occur. If you have comments concerning its accuracyi-7 C ite to “ETSI Standards Management Dept.“ at the address shown on the title page. 7 -_ i Foreword This Interim European Telecommunication Standard (I-ETS) has been produced by the Special Mobile Gr
5、oup (GSM) Technical Committee of the European Telecommunications Standards Institute (ETSI). This I-ITS specifies the Mobile Termination (MT) interfaces and Terminal Adaptation functions which enable the attachment of synchronous terminals to MTs within the European digital cellular telecommunicatio
6、ns system (phase 1). Reference is made within this I-ETS to the following ETSI Technical Specifications (NOTE 1): GSM 02.02 Bearer services supported by a GSM PLMN (Version 3.1.1). GSM 03.10 GSM 04.02 PLMN connection ypes (Version 3.3.0). GSM PLMN access reference configuration (Version 3.0.2). GSM
7、04.08 Mobile radio interface - layer 3 specification (Version 3.1 1 .O). GSM 04.21 GSM 04.22 GSM 07.01 GSM 07.03 GSM 09.06 GSM 09.07 Rate adaptation on the Mobile Station - Base Station System (MS-BSS) interface (Version 3.2.0). Radio link protocol for data and telematic services on the MS- BSS inte
8、rface (Version 3.6.0). General on terminal adaptation functions for Mobile Stations (Version 3.10.0). Terminal adaptation functions for services using synchronous bearer capabilities (Version 3.2.0). Interworking between a PLMN and a PSPDNASDN for support of packet switched data transmission service
9、s (Version 3.0.0). General requirements on interworking between the PLMN and the ISDN or PSTN (Version 3.6.0). The above ETSI-GSM Technical Specifications, together with the annex to this standard, are normat ive. NOTE 1: The GSM Technical Committee of ETSI has constituted stable and consistent docu
10、ments which give technical specifications for the implementation of the European digital cellular telecommunications system. Historically, these documents have been identified as %SM recommendations“. Some of these recommendations may subsequently become I-ETSs or Es, whilst some may continue with t
11、he status of ETSI-GSM Technical Specifications. These SI-GSM Technical Specifications are, for editorial reasons, still referred to as GSM recommendations in current GSM documents. The ETSI-GSM Technical Cornmittee numbering and version control system remains unchanged for the ETSI-GSM Technical Spe
12、cifications. NOTE 2: Items in this draft indicated as not complete, or requiring further study or work, are not required for the phase 1 implementation of the European digital cellular telecommunications system. -3 M 3VOV583 0017b80 9 j GSM 07.03 - version -3.2.0 - 1 ETSI GSM Releaced: ETSI PT12 Dat
13、e: January 1991 Recommendation: GSM 07.03 Title: Terminal Adaptation Functions for services using Synchronous Bearer Capabilities List of Contente: O: Scope 1. General 2. Terminal Adaptation Functions for Synchronous Transparent Services 3. Terminal Adaptation Functions for Synchronous Non Transpare
14、nt Services V- and S-series Interface procedures to 04.08 mapping 4. 50 X.21 Interface procedures to 04.08 mapping 6. Support for Packet Service Annex. L2R Functionality language: English -: 36 -4. O 1 1.1 1.2 . - - GSM 07.03 version 3.2.0 - 2 SCOPE This recommendationdefines Terminal Adaptation Fun
15、ctions (TAF) which are integrated in a Mobile Termination (MT) and which enable the attachment of Synchronous Terminals to en MT ( see GSM %!.CS ) , Tha yzncrl sspszts ef Terminal Adaptation Functions are contained in recommendation GCM 07.01. This recommendation covers support of synchro- nous data
16、 services (see GSM 02.02) for the following interfaces and procedures: - v.22 - V.22bis - V.26ter - V.32 - x.21 - X.2lbis - X.25 - X.32 - V.25bis - 1.420 DTE/DCE Interface DTE/DCE Interface DTE/DCE Interface DTE/DCE Interface DTE/DCE Interface DTE/DCE Interface Procedure . Procedure Procedure Interf
17、ace (S ) LAPB is the only synchronous non-transparent protocol which is considered here. GENERAL CUSTOMER ACCESS CONFIGURATION The GSM PLMN access reference configuration is described in figure 1 of GSM 04.02. This recommendation (GSM 07.03) specifically refers to the MTs which support terminal epui
18、pments (TE1 or TE2) that use synchronous bearer capabilities. -. TERMINAL ADAPTATION FUNCTION The TAF is functionally part of an MTO, MT1 or MT2 (see .recommendation GSM 04.02.). The terminal adaptation provides facilities to allow manual or automatic call control functions associated with alternate
19、 speech/data, speech followed by data and circuit switched data services, in case of V Series interfaces. The X.21 DTE/DCE interface allows only for automatic call control functions. The following functions are included: - Conversion of electrical, mechanical, functional and procedural characteristi
20、cs of the V-series, X-series and ISDN type interfaces to those required by a GSM PLMN 1.3 3404583 00L7b82 2 rn : GSM 07.03 - version 3.2.0 - 3 Bit rate adaptation of V-series and X-series data signalling rates and the ISDN 64 kbit/s to that provided in the GSM PLMN. The mapping of V. 25bis AUTO CALL
21、/AUTO ANSWER proce- dures and X.21 prc?cedurcs to the GSM FLf4u U,-channei signalling. The mapping functions necessary to convert S-inter- face signalling to PLMN D,-channel signalling. Synchronization procedure, which means the task of synchronizing the entry to and the exit from the data transfer
22、phase between two subscriber terminals. This is described in the recommendation GSM 07.01. . Filtering of channel control information. This is described in the recommendation GSM 07.01. Compatibility checking (see GSM 07.01) Layer 2 relaying (see Annex 1) Flow control In Call Modification function (
23、see section 4) TAF INTERFACING TO OTHER MT FUNCTIONS TAF interfacing is shown in figure 1. Mobility Management , TAF RR Management Channel Codec FEC I MMI I I Call Control I Figure 1. TAF interfacing to other MT functions -6- - - L = 3404583 O037683 4 E - - GSM 07.03 - version 3.2.0 - 4 2 TERMINAL A
24、DAPTATION FUNCTIONS FOR SYNCHRONOUS TRANSPARENT SERVICES Recommendation GSM 03.10 refers to the models for connection types supporting synchronous transparent services. 2.1 RATE ADAPTATION Rate adaptation on the MS-BS interface is described in GSM 04.21. The synchronous data services make use of the
25、 following rate adaptation functions: RA1, RA2, E?Al/RAl and M1. See also Figure 6 in GSM 03.10. .The D-bits of the rate adaptation frames are used to convey user data and the S- and X-bits are used to convey channel status information associated with the data bits in the data transfer state. For th
26、e S- and X-bits, a ZERO corresponds to the ON condition, a ONE to the OFF condition. 2.1.1 RATE ADAPTATION - V-SERIES This is provided as indicated in recommendation GSM 04.21. The functions applied in this case are shown in figure 2 (see model 2b in Fig. 6 / GSM 03.10). MT2 interface circuits (data
27、 and control) + R Figure 2. Rate adaptation for V-series terminals 2.1.2 RATE ADAPTATION - X.21 This is provided as indicated in recommendation GSM 04.21. The functions applied in this case are shown in a figure 3 (see model 2b in Fig. 6 / GSM 03.10). Figure 3. Rate adaptation for X.21 terminals -7
28、- i 7 GSM 07.03 - version 3.2.0 - 5 2.1.3 RATE ADAPTATION - S-INTERFACE The functions applied in this case are shown in figure 4 (see model 2a in Fig. 6 / GSM 03.10). Figure 4. Rate adaptation for S-interface There are two cases to be considered for the RA1 function : a) V-series interface For the V
29、-series type of terminal equipments the rate adaptation functions are as described in GSM 04.21. b) X.21-interface For terminal equipments using the X.21-interface the rate adaptation functions are identical to those described in GCM 04.21, but the notation used is as described in CCITT recommendati
30、on X.30/1.461. The notation used is as follows: The conversion of the user rates of 2.4 and 4.8 kbit/s to 8 kbit/s and user rate of 9.6 kbit/s to 16 kbit/s shall be implemented by means of the 40 bit frame structure shown in figure 5. Figure 5 shows that in addition to the basic frame, a two frame m
31、ultiframe is employed. In odd frames, octet O contains all zeroes, whilst in even frames octet O consists of a one followed by seven E bits. The order of bit transmission of the 40 bit frame is from left- to-right and top-to-bottom. This two frame multiframe corresponds to the 80 bit frame structure
32、 presented in GSM 04.21 as shown in figure 6. The 24 information bits Pl, P8,Q1, Q8, Rl,R8 of odd frames correspond with Dl,D24 and those of even frames correspond with D25,D48 respec- tively. For the status bits there is the following correspondance: odd frame SQ,X,SR,SP = Sl,X,S3,C4 and even frame
33、 SQ,X,SR,SP = S6,XS8,S9. -%A 3404583 0037685 8 i - - GSM 07.03 - version 3.2.0 - 6 I ! I Octet O Odd frames - ! I Even frames - i .I Bit number 12345678 O O O O O O O O 1 El E2 E3 E4 E5 E6 E7 Option for a manufacturer of mobile stations: In transparent mode support of a packet mode TE1 or TE2/TA, wh
34、ich uses flag stuffing. I Octet I I Octet 2 I 1 P1 P2 P3P4 P5 P6 SQ 1 P7 P8 Ql Q2 Q3 Q4 X 1 Octet 3 i i Octet 4 1 1 Q5 Q6 Q?. Q8 R1 R2 SR 1 R3 R4 R5 R6 R7 R8 SP Note - Bit X. if not used for the optional flow control or for the indication of the far end synchronization. shall be set to O (see CCITT
35、Recommendation i.46s/V. 110) X.30 TWO FRAME MULTIFRAME 00000000 1 P1 P2 P3P4 P5 P6 SQ 1. P7 P8 Ql Q2 Q3 Q4 X- Figure 5. 40 bit frame structure of CCITT X.30 V.110 80-BIT FRAME 00.0 o o o o o 1 D1 D2 D3 D4 D5 .D6 S1 1 D7 D8 D9 D10 D11 D12 X 8 1 65 66 Q7Q8 R1 R2 SR 1 R3 R4 R5 R6 R? R8 SP 5 1 P1 P2 P3
36、P4 P5 P6 SQ 5 1 Q5 Q6 Q? Q8 R1 R2 SR - 1 El E2 E3 E4 E5 E6 E? 1 P? P8 Q1 Q2 Q3 Q4 X 1 -D13 D14 D15 D16 D17 D18 S3 1 D19 D20 D21 D22 D23 D24 S4 1 D25 D26 D27 D28 D29 D30 S6 1 D31 D32 D33 D34 D35 D36 X 1 D3? D30 D39 1140 1141 1142 SU 1 El E2 E3 E4 E5 E6 E? Figure 6. Correspondance of X.30 and V.110 fr
37、ames F-q -9- 3404583 001768b T GSM 07.03 - version 3.2.0 - 7 2.2 INTERCHANGE CIRCUIT SIGNALLING MAPPING 2.2.1 V-SERIES INTERCHANGE CIRCUIT MAPPING The interface between the TE2 and the MT shall conform to CCITT recommendatim V.20. The signls reqired at this interface are shown in table 2. a) Signal
38、electrical characteristics at the interface shall conform to CCITT recommendation V28. . b) Interface function to status bit mapping Recommendation 04.21 refers to the frame structure and identifies the use of status bits for the carriage of signalling information. Status .bits The bits S and X are
39、used to convey channel status information associated with the data bits in the data transfer stage as shown below. The S-bits are put into two groups SA and SB to carry the condition of two interchange circuits. The X-bit is used to control the condition of circuit 106. The mechanism for proper assi
40、gnment of the control information from the transmitting signal rate adapter interface via these bits to the receiving signal rate adapter interface is shown below in Table 1. For the S and X bits, a ZERO corresponds to the ON condition, a ONE to the OFF condition. General mapping scheme 108 Si, S3,
41、S6, S8 = SA 107 105 S4, S9 = SB 1 o9 X 106 Frame synch and lOO/IWF Table 1. General mapping scheme for V-series interchange circuits /- 7. -o - _. .- - GSM 07.03 - version 3.2.0 - 8 Circuit Circuit Name Number Ground CT102 Common Return CT103 Transmitted CT104 Received data CT105 Request to CT106 Re
42、ady for CT107 Data set ready CT108.2 CT109 Data terminal Data channel received line signal detector CT114 CT115 CT125 Transmitter signal element timing Receiver signal element timing Calling in- dicator (Note) Data I Control Note: CT125 is used with the AUTO ANSWER function of the TAF. Table 2: Mini
43、mum set of V-series interchange circuits nt C1 The application of Network Independent Clocking to Synchronous data services is as defined in CCITT recommendation V.110. Receiver signal element timing (CT115) is generated by MT2. In the transparent case, this shall be synchronized to the output of RA
44、1 function. In the non transparent case it is output from the L2R on the basis of the current user data rate. A transition from ON to OFF condition shall nominally indicate the centre of each signal element on CT104. -I- 3404583 0017b88 3 j GSM 07.03 - version 3.2.0 - 9 Transmitter signal element ti
45、ming is generated by MT2 (CT114), this may be synchronized to CT115. In the case of alternate Speech/Group 3 Facsimile, there may be a Channel Mode Modify during the course of the facsimile portion of the. call. If this cccurs, triz User data rate changes and this is reflected to the v.24 interface
46、as a change in the clock speed on CT 114 and CT 115. 2.2.2 X.21 INTERCHANGE CIRCUIT MAPPING The interface between the TE2 and the MT shall conform to CCITT recommendations X.21 and X.24. The signals required at this interface are shown in Table 3. a) Signal electrical characteristics shall conform t
47、o CCITT recommendations X.26 (V.10) or X.27 (V.11) - see also paragraph 2.1 of CCITT recommendation x.21. b) Interface function to status bit mapping Recommendation 0421 refers to the frame structure and - identifies the use of status bits for the carriage of signalling information. Status bits (Sl,
48、S3,S4,S6,S8,S9) For the purpose of alignment with the case where the X.21 TE2 is connected to the MT via a TA conforming to CCITT recommendation X.30 (1.4611, the notation for the S-bits will be SP, SO and SR as in Figure 5 / GSM 07.03. For the bits SP, SO and SR, a ZERO corresponds to the ON condit
49、ion, a.ONE to the OFF condition. The bits SP, SQ and SR are used to convey channel associated status information. The mapping of the information on circuit C of the X.21 interface to the S bits and from the S bits to the circuit I in the distant interface should be done in such a way that the SP, SQ and SR bits are associated with the bit-groups P, Q and R. To assure proper and secure operation the mapping scheme has to be consistent with CCITT recommendations X.21 and X.24. The mechanism fo
