SIST I-ETS 300 245-1 E1:2003

• Abstract:

  Specify telephony terminal used at S/T interface of basic access to the ISDN, including electrical, logical and acoustical characteristics

• Status: Published
• Publication Date: 30-Nov-2003
• ICS: 33.080 - Integrated Services Digital Network (ISDN)
• Technical Committee: SS EIT - Technical Board for the electrotechnical, information technology and telecommunications fields
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-2003
• Due Date: 01-Dec-2003
• Completion Date: 01-Dec-2003
• Ref Project: ETSI I-ETS 300 245-1 ed.1 (1994-05) - Integrated Services Digital Network (ISDN); Technical characteristics of telephony terminals; Part 1: General

SIST I-ETS 300 245-1 E1:2003 is the Slovenian adoption of ETSI I-ETS 300 245-1, an Interim European Telecommunication Standard for ISDN telephony terminals. It specifies the electrical, logical and acoustical characteristics of telephony terminals used at the basic access S/T interface of ISDN, so the terminal can work correctly with the network and with other telephony equipment.

What does SIST I-ETS 300 245-1 E1:2003 specify?

SIST I-ETS 300 245-1 E1:2003 specifies the common technical characteristics for telephony terminals connected to the coincident S and T reference point of an ISDN basic access. The document is written for telephony terminals and for telephony functions in multimedia or multiservice terminals.

The scope is limited to additional characteristics beyond the ISDN basic access attachment requirements and other applicable standards. The foreword states that these characteristics are meant to improve performance, but the standard is not intended for type approval or other mandatory requirements.

The document is organized into clauses 1 to 8, followed by two annexes.

Annex	What it covers
Annex A	Normative test specifications, including DTMF measurements and general testing conditions
Annex B	Informative bibliography

Clauses 1 to 3 cover scope, normative references, and definitions and abbreviations. Clauses 4 to 7 cover access channel selection, call control, transmission aspects, and power feeding. Clause 8 covers physical modules such as the handset and audible alerting module.

What are the key requirements of SIST I-ETS 300 245-1 E1:2003?

The main requirements describe how an ISDN telephony terminal must set up calls, identify compatible calls, handle tones, and behave on the B-channel and D-channel. In practice, these requirements tell a designer what the terminal must signal to the network and what it must accept from the network.

Access and call setup

Clause 4 says the terminal shall be able to access any B-channel, and its functional behavior shall not depend on which B-channel is selected. That matters because the terminal should work the same way regardless of channel assignment.

Clause 5.1 requires the complete outgoing-call procedures for both en-bloc and overlap sending. For the telephony 3,1 kHz teleservice, the bearer capability shall be coded for speech with G.711, A-law. For the telephony 7 kHz teleservice, the terminal shall support fallback to telephony 3,1 kHz teleservice, and it shall also be possible to disable fallback.

Clause 5.1 also requires the High layer compatibility information element to be included when using telephony 3,1 kHz or 7 kHz teleservice. In practice, this helps avoid mismatch with multimedia or multiservice terminals. The Low layer compatibility information element may be used in most cases, but not when two Bearer capability information elements are included.

Incoming call compatibility

Clause 5.2 defines how the terminal checks incoming calls for compatibility. For 3,1 kHz telephony, the terminal checks Bearer capability coding such as speech or 3,1 kHz audio, and for 7 kHz telephony it checks for UDI-TA with the H.221/H.242 coding.

If High layer compatibility is analyzed, the terminal shall accept telephony calls when the high-layer characteristic is coded as telephony. If no High layer compatibility element is present, a call can still be accepted as a 3,1 kHz telephony call when the bearer capability indicates speech.

Clause 5.2.1.4 allows terminal selection by Multiple Subscriber Number (MSN) and/or subaddress when those data are stored in the terminal. In practice, this means a terminal can be programmed to ring only for selected numbers or subaddresses. Clause 5.2.2 adds special response rules for the designated terminal under Restricted power condition.

Information tones and DTMF

Clause 5.3 requires the terminal to pass network-provided tones and verbal announcements to the human user on the B-channel. It also allows the terminal to generate tones locally, either as a normal replacement for network signals or only when no B-channel is available.

Clause 5.4 covers Dual Tone Multi Frequency (DTMF) signalling. If DTMF is provided, the terminal shall send the tones on the connected B-channel using the same encoding algorithm as the speech transmission in use, and at minimum this shall be available with G.711, A-law. The standard also defines the signalling frequencies, allowed frequency deviation, level and timing. This is the part that matters for keypad dialing and automated tone tests.

Transmission and power feeding

Clause 6 states that the default speech encoding law shall be G.711, A-law at 64 kbit/s, with any other coding only as an additional option. The digital interface is defined as a 0 dBr point.

Clause 7 links the terminal’s power supply behavior to ETS 300 012 for Power source 1. It also allows a terminal to be a designated terminal for Restricted power condition if it meets the relevant requirements, and it lets the option be disabled. A non-designated terminal shall comply with leakage current requirements under Restricted power condition.

Physical modules

Clause 8 gives requirements for the handset and the audible alerting module. The audible alerting module shall meet the sound pressure level requirements of ETS 300 085, and at least one setting shall satisfy the frequency-spectrum requirement. For real products, this affects how clearly the ringing or alert signal can be heard, especially in noisy or hearing-impaired use cases.

What terms does SIST I-ETS 300 245-1 E1:2003 define?

Telephony 3,1 kHz teleservice - The narrowband telephony service used as the basic telephony mode in this standard.

Telephony 7 kHz teleservice - The wider-band telephony service associated with 7 kHz audio coding and related fallback handling.

Restricted power condition - A power state defined by I.430 and indicated by reversed polarity of the phantom voltage at the coincident S and T reference point.

Designated terminal - The terminal allowed to draw power from Power source 1 under Restricted power condition.

Telephony terminal - A terminal that supports telephony 3,1 kHz teleservice and/or telephony 7 kHz teleservice.

Multiservice terminal - A terminal that supports more than one service, such as a bearer service or teleservice.

DTMF - Dual Tone Multi Frequency, also noted as MFPB (Multi Frequency Push Button), the tone system used for keypad signalling.

UDI-TA - Unrestricted Digital Information with Tones and Announcements, the bearer capability used for 7 kHz audio-type operation.

Who uses SIST I-ETS 300 245-1 E1:2003?

Manufacturers of ISDN telephony terminals use this standard when designing terminal behavior at the basic access interface. Test laboratories use it to check signalling, compatibility, DTMF performance and power-feeding behavior.

Quality managers and buyers use it when they need a clear technical reference for telephony functions in TE1 terminals, including telephony functions inside multimedia or multiservice terminals. Network and interoperability engineers use it to understand how terminals should react to incoming calls, bearer capability coding and progress information.

The standard also matters for terminals with optional features such as locally generated tones, DTMF signalling, MSN/subaddress selection, and operation under Restricted power condition.

What changed in SIST I-ETS 300 245-1 E1:2003 from the previous edition?

SIST I-ETS 300 245-1 E1:2003 is identical to I-ETS 300 245-1 Edition 1.

Which standards are used with SIST I-ETS 300 245-1 E1:2003?

The standard relies on a set of companion documents for attachment requirements, service descriptions, call control and test methods.

• ETS 300 085 - supplies handset attachment requirements for 3,1 kHz telephony and the general testing conditions for Annex A.
• ETS 300 104 and ETS 300 153 - provide the ISDN basic access attachment requirements and Layer 3 aspects that this standard builds on.
• CCITT Recommendation I.411 - gives the reference configurations for the ISDN user-network interface.
• CCITT Recommendations P.10 and G.701 - provide the vocabulary used for telephony, transmission quality and PCM terms.
• ETS 300 111 and ETS 300 263 - define the 3,1 kHz and 7 kHz telephony teleservices referenced in the scope and call-handling clauses.
• CCITT Recommendation I.430 and ETS 300 012 - define basic access layer 1 and power-feeding behavior, including Restricted power condition.
• ETS 300 102-1 - supplies the basic call control, bearer capability, high layer compatibility and low layer compatibility coding used throughout clause 5.
• ETS 300 082, I-ETS 300 281 and ETS 300 267 - cover end-to-end compatibility, terminal requirements for 7 kHz telephony and DSS1 signaling procedures.
• prI-ETS 300 322 - provides the test suite used to check bearer capability coding.
• CCITT Recommendations G.711, G.722, E.164 and G.101 - provide the speech coding, 7 kHz audio coding, numbering plan and transmission-plan basis used by this standard.

The foreword also lists the companion parts of the series: Part 2 handset telephony, Part 3 loudspeaking and handsfree telephony, Part 4 interface for additional equipment, Part 5 and Part 6 wideband 7 kHz telephony, Part 7 locally generated information tones, and Part 8 terminal application of 16 kbit/s speech coding algorithms.

What does the SIST I-ETS 300 245-1 E1:2003 document contain?

The document contains detailed call-setup and compatibility procedures, including bearer capability coding, high-layer and low-layer compatibility handling, and terminal selection by MSN and subaddress. It also describes how the terminal should react to network tones and announcements on the B-channel, and how locally generated tones may replace or supplement network signals.

Annex A provides the test specifications for DTMF frequency deviation, signal level and signal timing, including where the measurements are taken. Figure 1 gives the DTMF signalling matrix for the keypad digits and symbols, so test labs know which dual-tone pairs correspond to each code.

Clause 7 and clause 8 add power-feeding requirements and physical-module behavior for the handset and audible alerting module. Annex B lists background references used by the document.

SLOVENSKI STANDARD
01-december-2003
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Integrated Services Digital Network (ISDN); Technical characteristics of telephony
terminals; Part 1: General
Ta slovenski standard je istoveten z: I-ETS 300 245-1 Edition 1
ICS:
33.080 Digitalno omrežje z Integrated Services Digital
integriranimi storitvami Network (ISDN)
(ISDN)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

INTERIM
EUROPEAN I-ETS 300 245-1
TELECOMMUNICATION May 1994
STANDARD
Source: ETSI TC-TE Reference: T/TE 10-07 (A)
ICS: 33.080
ISDN, telephony terminals
Key words:
Integrated Services Digital Network (ISDN);
Technical characteristics of telephony terminals
Part 1: General
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
F-06921 Sophia Antipolis CEDEX - FRANCE
Postal address:
650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE
Office address:
c=fr, a=atlas, p=etsi, s=secretariat - [e-mail]
X.400: Internet:
Tel.: [phone] - Fax: [phone]
Copyright Notification: No part may be reproduced except as authorized by written permission. The copyright and the
foregoing restriction extend to reproduction in all media.
© European Telecommunications Standards Institute 1994. All rights reserved.
New presentation - see History box

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I-ETS 300 245-1: May 1994
Whilst every care has been taken in the preparation and publication of this document, errors in content,
typographical or otherwise, may occur. If you have comments concerning its accuracy, please write to
"ETSI Editing and Committee Support Dept." at the address shown on the title page.

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I-ETS 300 245-1: May 1994
Contents
Foreword.5
1 Scope .7
2 Normative references .7
3 Definitions, symbols and abbreviations .9
3.1 Definitions.9
3.2 Abbreviations.9
4 Access channel selection . 10
5 Call control functions. 10
5.1 Outgoing calls. 10
5.1.1 Coding of Bearer capability information element. 10
5.1.1.1 Telephony 3,1 kHz teleservice . 10
5.1.1.2 Telephony 7 kHz teleservice . 10
5.1.1.3 Short term solution before the introduction of telephony 7
kHz teleservice (optional) . 10
5.1.1.4 Other services. 11
5.1.2 Coding of High layer compatibility information element. 11
5.1.3 Coding of Low layer compatibility information element. 11
5.1.4 Coding of Called Party Number information element. 11
5.1.5 Indication of resultant service . 12
5.2 Incoming calls. 12
5.2.1 Compatibility checking . 12
5.2.1.1 Analysis of Bearer capability information element . 12
5.2.1.2 Analysis of High layer compatibility information element . 13
5.2.1.3 Analysis of Low layer compatibility information element . 13
5.2.1.4 Terminal selection. 13
5.2.2 Compatibility checking for the designated terminal under Restricted power
condition. 14
5.2.3 Response to incoming calls . 14
5.3 Information tones . 14
5.3.1 Transmission of tones and announcements from the network. 14
5.3.2 Generation of tones by the terminal . 15
5.4 Dual Tone Multi Frequency (DTMF) signalling. 15
5.4.1 General . 15
5.4.2 Connection to B-channel . 16
5.4.3 Signalling frequencies . 16
5.4.4 Frequency deviation. 16
5.4.5 Level. 16
5.4.6 Timing . 16
6 Transmission aspects . 16
6.1 Encoding . 16
6.2 Relative level . 16
7 Power feeding. 17
7.1 General conditions . 17
7.2 Restricted power condition. 17
7.2.1 Leakage current. 17
7.2.2 Operation of the designated terminal under Restricted power conditions. 17

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I-ETS 300 245-1: May 1994
8 Physical modules.17
8.1 Handset.17
8.2 Audible alerting module.17
8.2.1 Sound pressure level .17
8.2.2 Frequency spectrum .17
Annex A (normative): Test specifications . 19
A.1 General conditions for testing.19
A.2 DTMF measurements .19
A.2.1 Frequency deviation.19
A.2.2 Signal level .19
A.2.3 Signal timing .19
Annex B (informative): Bibliography.20
History .21

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I-ETS 300 245-1: May 1994
Foreword
This Interim European Telecommunication Standard (I-ETS) was prepared by the Terminal Equipment (TE)
Technical Committee of the European Telecommunications Standards Institute (ETSI).
An ETSI standard may be given I-ETS status as it is regarded either as a provisional solution ahead of a more
advanced standard, or because it is immature and requires a "trial period". The life of an I-ETS is limited, at first,
to three years after which it can be converted into an European Telecommunication Standard (ETS), have its life
extended for a further two years, be replaced by a new version of the I-ETS or, finally, be withdrawn.
This is the first part of an I-ETS which is currently intended to comprise eight parts.
This I-ETS specifies technical characteristics for Integrated Services Digital Network (ISDN) telephony
terminals as described in the scope of this I-ETS. The characteristics are additional to type approval
requirements to which the terminal equipment is subject. The additional characteristics are meant to give
improved performance.
In the present version of the I-ETS the following parts are included:
Part 1: General.
Part 2: PCM A-law, handset telephony.
Part 3: PCM A-law, loudspeaking and handsfree telephony.
Part 4: Interface for additional equipment.
Part 5: Wideband (7 kHz) handset telephony.
Part 6: Wideband (7 kHz) handsfree telephony.
Part 7: Locally generated information tones.
Part 8: Terminal application of 16 kbit/s speech coding algorithms.
NOTE: Part 8 is still under study within ETSI.

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I-ETS 300 245-1: May 1994
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I-ETS 300 245-1: May 1994
1 Scope
This Interim European Telecommunication Standard (I-ETS) specifies the technical characteristics
(electrical, logical and acoustic) for telephony terminals to be used at the basic access of the coincident S
and T reference point of the Integrated Services Digital Network (ISDN). The characteristics of this I-ETS
are additional to those of the ISDN basic access attachment requirements (ETS 300 085 [1], ETS 300 104
[2] and ETS 300 153 [3]) and of any other Standard or attachment requirements to which the terminal
equipment is subject. The additional characteristics of this I-ETS are meant to give improved performance
relative to the attachment ETSs. However, this I-ETS is not intended to be used for type approval
purposes or other mandatory requirements.
This I-ETS is applicable to telephony terminals as well as to telephony functions of multimedia or
multiservice terminals.
This I-ETS is applicable to Terminal Equipment (TE) of the functional group defined as Terminal Equipment
Type 1 (TE1) in CCITT Recommendation I.411 [4].
The characteristics specified in this I-ETS cover a number of functions or facilities which can be combined
to form a particular terminal. The characteristics relevant for each speech coding algorithm, function or
facility can be found in separate parts of the I-ETS. This Part (Part 1) covers the introduction to the I-ETS
and the characteristics which are common to telephony terminals to be connected to a coincident S and T
reference point to a public telecommunication network presented as an ISDN basic access point.
For multimedia or multiservice terminals, other requirements or standards may apply instead of, or in
addition to, this I-ETS.
TE specially designed for the disabled (e.g. with amplification of received speech as an aid for the
hard-of-hearing), may have characteristics which may be specified in separate parts of this I-ETS.
TE using a radio link (e.g. cordless telephones) will, due to the characteristics of the radio channel, be
specified separately.
NOTE: In some countries, an interim ISDN service corresponding to, but not wholly compatible
with, the ISDN basic access standards may be provided. This I-ETS does not apply for
connection to such a service.
2 Normative references
This I-ETS incorporates by dated or undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text and the publications are listed
hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply
to this I-ETS only when incorporated in it by amendment or revision. For undated references the latest
edition of the publication referenced to applies.
[1] ETS 300 085 (1990): "Integrated Services Digital Network (ISDN); 3,1 kHz
telephony teleservice, Attachment requirements for handset terminals".
[2] ETS 300 104 (1991): "Integrated Services Digital Network (ISDN); Attachment
requirements for terminal equipment to connect to an ISDN using ISDN basic
access, Layer 3 aspects (Candidate NET 3, Part 2)".
[3] ETS 300 153 (1992): "Integrated Services Digital Network (ISDN); Attachment
requirements for terminal equipment to connect to an ISDN using ISDN basic
access (Candidate NET 3, Part 1)".
[4] CCITT Recommendation I.411 (1988): "Integrated Services Digital Network
(ISDN) user-network interfaces - Reference configurations".

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I-ETS 300 245-1: May 1994
[5] CCITT Recommendation P.10 (1988): "Vocabulary of terms on telephone
transmission quality and telephone sets".
[6] CCITT Recommendation G.701 (1988): "Vocabulary of digital transmission and
multiplexing, and pulse code modulation (PCM) terms".
[7] ETS 300 111 (1992): "Integrated Services Digital Network (ISDN); Telephony
3,1 kHz teleservice, Service description".
[8] ETS 300 263 (1992): "Integrated Services Digital Network (ISDN); Telephony 7
kHz teleservice, Service description".
[9] CCITT Recommendation I.430 (1988): "Integrated Services Digital Network
(ISDN) user-network interfaces: layer 1 recommendations".
[10] ETS 300 102-1 (1990) (including Amendment 1 (1993)): "Integrated Services
Digital Network (ISDN); User-network interface layer 3, Specification for basic
call control".
[11] ETS 300 082 (1992): "Integrated Services Digital Network (ISDN); 3,1 kHz
telephony teleservice, End-to-end compatibility".
[12] I-ETS 300 281: "Integrated Services Digital Network (ISDN); Telephony 7 kHz
teleservice, Terminal requirements necessary for end-to-end compatibility".
[13] ETS 300 267 (1993): "Integrated Services Digital Network (ISDN); Telephony 7
kHz and videotelephony teleservices; Digital Subscriber Signalling System No.
one DSS1) protocol".
[14] prI-ETS 300 322: "Integrated Services Digital Network (ISDN); Digital Subscriber
Signalling System No. one (DSS1), Abstract test Suite (ATS) for user of
signalling-network-layer protocol for circuit-mode basic call control".
[15] CCITT Recommendation G.711 (1988): "Pulse code modulation (PCM) of voice
frequencies".
[16] CCITT Recommendation G.722 (1988): "7 kHz audio-coding within 64 kbit/s".
[17] CCITT Recommendation E.164 (1991): "Numbering plan for the ISDN era".
[18] CCITT Recommendation G.101 (1988): "The transmission plan".
[19] ETS 300 012 (1992): "Integrated Services Digital Network (ISDN); Basic
user-network interface, Layer 1 specification and test principles".

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I-ETS 300 245-1: May 1994
3 Definitions, symbols and abbreviations
3.1 Definitions
For the purposes of this I-ETS, the relevant definitions given in CCITT Recommendations P.10 [5] and
G.701 [6] apply along with the following.
Telephony 3,1 kHz teleservice: A description of the telephony 3,1 kHz teleservice is to be found in ETS
300 111 [7].
Telephony 7 kHz teleservice: A description of the telephony 7 kHz teleservice is to be found in ETS 300
263 [8].
Restricted power condition: As defined in CCITT Recommendation I.430 [9]. The condition is indicated
by the reversed polarity of the phantom voltage at the coincident S and T reference point.
NOTE: For some networks restricted power condition will be the normal operating mode.
Designated terminal: Refers to the terminal which is permitted to draw power from Power source 1 under
Restricted power conditions as specified in CCITT Recommendation I.430 [9].
Telephony terminal: A terminal which supports the telephony 3,1 kHz teleservice and/or the telephony 7
kHz teleservice.
3,1 kHz terminal: A terminal which supports the telephony 3,1 kHz teleservice.
7 kHz terminal: A terminal which supports the telephony 7 kHz teleservice.
Loudspeaking telephony terminal: A handset telephony terminal using a loudspeaker assosiated with an
amplifier as a telephone receiver (see CCITT Recommendation P.10 [5]).
Handsfree telephony terminal: A telephony terminal using a loudspeaker associated with an amplifier as
a telephone receiver and which can be used without a handset (see CCITT Recommendation P.10 [5]).
Multiservice terminal: A terminal which supports more than one service (bearer service or teleservice).
Multimedia terminal: A terminal which simultaneously supports two or more media (e.g. audio, video, text,
data).
Digital interface: Refers to the B-channels available at the coincident S and T reference point at an ISDN
basic access.
3.2 Abbreviations
For the purposes of this I-ETS, the following abbreviations, plus the relevant abbreviations in CCITT
Recommendations P.10 [5] and G.701 [6], apply.
BC Bearer Capability (see ETS 300 102-1 [10])
DTMF Dual Tone Multi Frequency (the same as MFPB - Multi Frequency Push Button)
ETS European Telecommunication Standard
ETSI European Telecommunications Standards Institute
HLC High Layer Compatibility (see ETS 300 102-1 [10])
I-ETS Interim European Telecommunication Standard
ISDN Integrated Services Digital Network
LLC Low Layer Compatibility (see ETS 300 102-1 [10])
UDI Unrestricted Digital Information (see ETS 300 102-1 [10])
UDI-TA Unrestricted Digital Information with Tones and Announcements (previously
called 7 kHz audio in ETS 300 102-1 [10])

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I-ETS 300 245-1: May 1994
4 Access channel selection
Access through any B-channel shall be possible. Channel allocation shall be in accordance with ETS
300 102-1 [10].
The functional characteristics of the terminal shall be independent of the B-channel selected.
5 Call control functions
Call control functions for the telephony 3,1 kHz teleservice are specified in ETS 300 082 [11] and ETS
300 102-1 [10]. Call control functions for the telephony 7 kHz teleservice are specified in I-ETS 300 281
[12] and ETS 300 267 [13]. Call control functions for other telephony functions or services are specified
below or in other parts of this I-ETS.
5.1 Outgoing calls
The complete procedures for both en-bloc and overlap sending according to ETS 300 102-1 [10] shall be
implemented.
5.1.1 Coding of Bearer capability information element
Compliance to the requirements specified in subclause 5.1.1 shall be checked using the tests specified in
prI-ETS 300 322 [14].
5.1.1.1 Telephony 3,1 kHz teleservice
When initiating an outgoing call on the telephony 3,1 kHz teleservice, the information transfer capability field
of the Bearer capability information element(s) in the outgoing SETUP message shall be set to "speech"
and the user information layer 1 protocol field shall be set to "G.711, A-law" as specified in ETS 300 102-1
[10], subclause 4.5.5.
5.1.1.2 Telephony 7 kHz teleservice
When initiating an outgoing call on the telephony 7 kHz teleservice a fallback procedure to the telephony
3,1 kHz teleservice shall be available (fallback allowed).
NOTE: When this option is used, the network will reserve any required echo cancellation
devices, A-law to μ-law convertors, etc., in case a speech information transfer
capability is used for the resultant connection.
It shall be possible to disable the fallback procedure (fallback not allowed).
The signalling procedures for fallback allowed and fallback not allowed are specified in ETS 300 267 [13],
subclause 6.5.1.
5.1.1.3 Short term solution before the introduction of telephony 7 kHz teleservice (optional)
For an interim period of time, some networks need not support the information transfer capability value
"UDI-TA" in the Bearer capability information element(s) and the fallback procedure (the use of two Bearer
capability information element(s) in the SETUP message).
In the first case, if a single Bearer Capability element, coded as specified in subclause 5.1.1.2 is sent, the
call will be rejected by the network.
In the second case, if two Bearer Capability elements, coded as specified in subclause 5.1.1.2 are sent,
only the first Bearer Capability element (containing the "speech" information transfer capability value) will
be transmitted by the network to the called terminal.
As a short term procedure, where a terminal is attached to a network that does not support the normal
operation as defined in the previous subclauses, the user may obtain a service similar to the telephony 7

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I-ETS 300 245-1: May 1994
kHz teleservice, possibly without tones and announcements, by requesting the circuit mode 64 kbit/s
unrestricted 8 kHz structured bearer service category ("UDI"), with the user information layer 1 protocol
field specifying "Recommendations H.221 and H.242", as specified in I-ETS 300 281 [12], subclause 5.5.
5.1.1.4 Other services
In the case of other speech coding algorithms, a 64 kbit/s transparent channel may be required. In those
cases "UDI-TA" or "UDI" can be used for the information transfer capability field of the Bearer capability
information element(s). Details for the use of these Bearer Capability elements are given in other parts of
this I-ETS and in other relevant standards (e.g. ETS 300 102-1 [10], subclause 4.5.5).
NOTE: If octet 3 of the Bearer capability information element(s) indicates "speech", "3,1 kHz
audio" or "UDI-TA", networks conforming to ETS 300 102-1 [10] and ETS 300 267 [13]
will provide information tones encoded to A-law in accordance with CCITT
Recommendation G.711 [15] and transmitted on the B-channel (see also subclause
5.3).
5.1.2 Coding of High layer compatibility information element
In order to avoid possible compatibility problems between a basic 3,1 kHz terminal (supporting only
telephony 3,1 kHz teleservice) and a multimedia or multiservice terminal, the High layer compatibility
information element(s) shall be included in the SETUP message from any telephony terminal complying
with this I-ETS when using telephony 3,1 kHz or 7 kHz teleservice.
The encoding of the High layer compatibility information element(s) for th
...