1 Scope

27.0023GPPTerminal Adaptation Functions (TAF) for services using asynchronous bearer capabilitiesTS

The present document defines the interfaces and Terminal Adaptation Functions (TAF) integral to a Mobile Termination (MT) which enable the use of asynchronous bearer services in the PLMN and the attachment of asynchronous terminals to a MT (see 3GPP TS 24.002 [3] and 3GPP TS 23.101 [6]).

The general aspects of Terminal Adaptation Functions are contained in 3GPP TS 27.001 [10].

The present document covers support of these services for the following interfaces and procedures:

(i) ITU-T V.14 [16] procedures.

(ii) ITU-T  V.21 [17] DTE/DCE interface.

(iii) ITU-T  V.22bis [18] DTE/DCE interface.

(iv) ITU-T  V.32 [24] DTE/DCE procedures.

(v) ITU-T  I.420 [14] S interface.

(vi) ITU-T  V.250 [22] signalling procedures.

The asynchronous data rates between the MT and the IWF are defined in 3GPP TS 22.002 [5].

NOTE: From GSM R99 onwards the following services are no longer required in a PLMN:

– the dual Bearer Services "alternate speech/data" and "speech followed by data";

– the dedicated services for PAD and Packet access;

– the BS 21 … 26 and BS 31 … 34.

The support of these services is still optional. The specification of these services is not within the scope of the present document. For that, the reader is referred to GSM Release 98.

NOTE: Please note that the Gb interface does not play any role in the scope of the present document although the term "A/Gb mode" is used. GERAN Iu mode is for further study.

1.1 References

The following documents contain provisions which, through reference in this text, constitute provisions of the present document.

– References are either specific (identified by date of publication, edition number, version number, etc.) or non‑specific.

– For a specific reference, subsequent revisions do not apply.

– For a non-specific reference, the latest version applies.

[1] Void.

[2] 3GPP TS 43.010: "GSM Public Land Mobile Network (PLMN) connection types".

[3] 3GPP TS 24.002: "GSM-UMTS Public Land Mobile Network (PLMN) access reference configuration".

[4] 3GPP TS 44.021: "Rate adaption on the Mobile Station – Base Station System (MS ‑ BSS) interface".

[5] 3GPP TS 22.002: "Circuit Bearer Services (BS) supported by a Public Land Mobile Network (PLMN)".

[6] 3GPP TS 23.101: "General UMTS Architecture".

[7] 3GPP TR 23.910: "Circuit Switched Data Bearer Services".

[8] 3GPP TS 24.008: "Mobile Radio Interface Layer 3 specification; Core Network Protocols-Stage 3".

[9] 3GPP TS 24.022: "Radio Link Protocol (RLP) for Circuit Switched Bearer and Teleservices".

[10] 3GPP TS 27.001: "General on Terminal Adaptation Functions (TAF) for Mobile Stations (MS)".

[11] 3GPP TS 27.007: "AT command set for 3G User Equipment (UE)".

[12] 3GPP TR 21.905: "Vocabulary for 3GPP Specifications".

[13] 3GPP TS 29.007: "General requirements on Interworking between the Public Land Mobile Network (PLMN) and the Integrated Services Digital Network (ISDN) or Public Switched Telephone Network (PSTN)".

[14] ITU-T Recommendation I.420 (1998):"Basic user‑network interface".

[15] ITU-T Recommendation V.4 (1988): "General structure of signals of international alphabet No.5 code for character oriented data transmission over public telephone networks".

[16] ITU-T Recommendation V.14 (1993): "Transmission of start‑stop characters over synchronous bearer channels".

[17] ITU-T Recommendation V.21 (1988): "300 bits per second duplex modem standardized for use in the general switched telephone network".

[18] ITU-T Recommendation V.22bis (1988): "2400 bits per second duplex modem using the frequency division technique standardized for use on the general switched telephone network and on point-to-point 2-wire leased telephone-type circuits".

[19] ITU-T Recommendation V.24 (1996): "List of definitions for interchange circuits between data terminal equipment (DTE) and data circuit‑terminating equipment (DCE)".

[20] ITU-T Recommendation V.25 (1996): "Automatic answering equipment and general procedures for automatic calling equipment on the general switched telephone network including procedures for disabling of echo control devices for both manually and automatically established calls".

[21] Void.

[22] ITU‑T Recommendation V.250 (1999): "Serial asynchronous automatic dialling and control".

[23] ITU‑T Recommendation V.28 (1993): "Electrical characteristics for unbalanced double-current interchange circuits".

[24] ITU-T Recommendation V.32 (1993): "A family of 2‑wire, duplex modems operating at data signalling rates of up to 9600 bit/s for use in the general switched telephone network and on leased telephone‑type circuits".

[25] ITU-T Recommendation V.42 (1996): "Error‑correcting procedures for DCEs using asynchronous‑to‑synchronous conversion".

[26] ITU‑T Recommendation V.42 bis (1990): "Data compression procedures for data circuit-terminating equipment (DCE) using error correction procedures".

[27] ITU-T Recommendation V.110 (1996): "Support of data terminal equipments with V‑Series interfaces by an integrated services digital network".

[28] ITU-T Recommendation X.28 (1997): "DTE/DCE interface for a start‑stop mode Data Terminal Equipment accessing the Packet Assembly/Disassembly facility (PAD) in a public data network situated in the same country".

[29] Personal Computer Memory Card Association: "PCMCIA 2.1 or PC‑Card 3.0 electrical specification or later revisions".

[30] Infrared Data Association IrDA "IrPHY Physical layer signalling standard".

[31] ISO 2110 (1989): "Data communication – 25-pole DTE/DCE interface connector and contact number assignments".

[32] ITU-T Recommendation Q.931 (1998): "ISDN user-network interface layer 3 specification for basic call control".

1.2 Abbreviations

In addition to the abbreviations used in the present document that are listed in TR 21.905 [12] the following internal abbreviations are used:

CFI Call Failure Indication

CRN Call Request with Number

DIC Disregard Incoming Call

IA5 International Alphabet no. 5

INC INcoming Call

INV INValid

ITU-T ITU-Telecommunication Standardization Sector

VAL VALid

1.3 Definitions

The term ‘mobile station’ (MS) in the present document is synonymous with the term ‘user equipment’ (UE ) as defined in 3GPP TR 21.905 [12].

The term ‘TE2’ in the present document is synonymous with the term ‘TE’ as defined in 3GPP TR 21.905 [12].

The term ‘MT2’ in the present document is synonymous with the term ‘MT’ as defined in 3GPP TR 21.905 [12].

In addition to the definitions used in the present document that are listed in TR 21.905 [12] the following internal definitions are used:

A/Gb mode: indicates that the text applies only to a system or sub-system which operate in A/Gb mode of operation, i.e. with a functional division that is in accordance with the use of an A or a Gb interface between the radio access network and the core network

Iu mode: indicates that the text applies only to a system or a sub-system which operates in Iu mode of operation, i.e. with a functional division that is in accordance with the use of an Iu-CS or Iu-PS interface between the radio access network and the core network