SIST I-ETS 300 245-1 E1:2003

Integrated Services Digital Network (ISDN); Technical characteristics of telephony terminals; Part 1: General

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

Digitalno omrežje z integriranimi storitvami (ISDN) – Tehnične karakteristike telefonskih terminalov 1. del: Splošno

General Information

• 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

Standards Content (Sample)

SLOVENSKI STANDARD
SIST I-ETS 300 245-1 E1:2003
01-december-2003
'LJLWDOQRRPUHåMH]LQWHJULUDQLPLVWRULWYDPL,6'1±7HKQLþQHNDUDNWHULVWLNH
WHOHIRQVNLKWHUPLQDORYGHO6SORãQR
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)
SIST I-ETS 300 245-1 E1:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST I-ETS 300 245-1 E1:2003

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SIST I-ETS 300 245-1 E1:2003
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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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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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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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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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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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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[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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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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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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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 the telephony 3,1 kHz teleservice
and for the telephony 7 kHz teleservice shall be as specified in ETS 300 102-1 [10], subclause 4.5.16, with
the high layer characteristic identification field set to "telephony".
Compliance shall be checked using the tests specified in prI-ETS 300 322 [14].
5.1.3 Coding of Low layer compatibility information element
In order to avoid possible compatibility problems between a basic 3,1 kHz terminal and a multimedia or
multiservice terminal, the Low layer compatibility information element(s) may, in most cases, be included in
the SETUP message from telephony terminals.
In the case where two Bearer capability information elements are included in the SETUP message the Low
layer compatibility information element(s) shall not be included in the SETUP message.
If the Low layer compatibility information element(s) is included in the SETUP message the encoding of the
element for telephony 3,1 kHz teleservice shall be as specified in ETS 300 102-1 [10], subclause 4.5.18,
with the information transfer capability field set to "speech" and, if optionally provided, the user information
layer 1 protocol field set to "G.711, A-law".
Compliance shall be checked using the tests specified in prI-ETS 300 322 [14].
5.1.4 Coding of Called Party Number information element
When initiating an outgoing call on a telephony teleservice (3,1 kHz or 7 kHz), the default coding of the
"Type of number" and "Numbering plan identification" fields in the information element shall both be
"unknown" as specified in ETS 300 102-1 [10], subclause 4.5.8.
In cases where it is possible for the human user to control the content of this element, other codings may
be appropriate. See ETS 300 102-1 [10], subclause 4.5.8.
Compliance shall be checked using the tests specified in prI-ETS 300 322 [14].
NOTE: In the dialling procedure the separation between the Called Party Number and the
Called Party Subaddress is for further study.

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5.1.5 Indication of resultant service
If the originating terminal specifies a preferred service with fallback allowed, the resultant service shall be
indicated to the originating terminal by the procedures specified in ETS 300 267 [13], Clauses 5 and 6. If
fallback occurs, the requirements for telephony 7 kHz teleservice do no longer apply.
5.2 Incoming calls
5.2.1 Compatibility checking
For a multiservice terminal which supports the telephony 3,1 or 7 kHz teleservice, the terminal shall, in
association with its function of supporting these services, meet the requirements specified in subclause 5.2
of this I-ETS for handling incoming telephony calls. However, in association with the support of other
bearer services or teleservices, it may accept as compatible incoming calls with Bearer capability, High
layer compatibility and Low layer compatibility information elements other than those specified in that
subclause.
NOTE: In the future, there may exist telephony terminals which requires Bearer Capabilities
other than "speech", "3,1 kHz audio telephony" or "UDI-TA" as well as other High layer
compatibility information element(s) (e.g. low bit-rate telephony and multiservice
terminals). Interworking between such terminals and 3,1 kHz telephony terminals is
envisaged. The inclusion of compatibility checking procedures which take into account
this interworking is for further study.
5.2.1.1 Analysis of Bearer capability information element
A terminal which is using CCITT Recommendation G.711 [15] A-law speech encoding as the only mode of
operation or as one of several modes of operation shall, in association with the support of the telephony
3,1 kHz teleservice, consider the Bearer Capability to be compatible if the Bearer capability information
element(s) in the incoming SETUP message is coded as specified below:
- the user information layer 1 protocol is coded as "G.711, A-law";
- the information transfer capability field is coded as "speech", or "3,1 kHz audio".
The coding "3,1 kHz audio" shall only be accepted if it is combined with a Progress indicator (progress
description #1 (call is not end-to-end ISDN: further progress information may be available in-band) or #3
(origination address is non-ISDN)). Details can be found in ETS 300 102-1 [10].
A 7 kHz terminal (which supports 7 kHz telephony using CCITT Recommendation G.722 [16] speech
encoding) shall consider the Bearer capability information element(s) in the incoming SETUP message as
compatible if one Bearer Capability element has the information transfer capability field set to "UDI-TA"
and the user information layer 1 protocol field coded as "Recommendations H.221/H.242".
If two Bearer Capability elements are received in the incoming SETUP message and the terminal is
compatible to both, the last Bearer Capability element shall be regarded as the one indicating the
preferred mode of operation.
As a short term procedure, in order to provide a capability similar to the telephony 7 kHz teleservice, the
information transfer field of the Bearer capability information element(s) can, optionally, be coded as
"UDI". In order for this mechanism to operate, the destination terminal shall accept, as compatible, each of
the two BC values "UDI-TA" and "UDI". The acceptance of the information transfer capability field value
"UDI" for this purpose is, therefore, an allowed option. If the user information layer 1 protocol field is
included in the Bearer capability information element(s), for this purpose it shall be coded as
"H.221/H.242".
For the possible acceptance of other Bearer capability information element(s), see subclause 5.2.1.

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Compliance shall be checked using the tests specified in prI-ETS 300 322 [14].
NOTE 1: Communication with CCITT Recommendation G.711 [15] μ-law terminals over a
transparent 64 kbit/s c
...