SIST ES 204 009 V1.1.1:2025

SLOVENSKI STANDARD
01-november-2025
Človeški dejavniki (HF) - Zahteve za interoperabilne storitve celovitega pogovora
Human Factors (HF) - Requirements for interoperable total conversation services
Ta slovenski standard je istoveten z: ETSI ES 204 009 V1.1.1 (2025-08)
ICS:
33.040.01 Telekomunikacijski sistemi Telecommunication systems
na splošno in general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

ETSI STANDARD
Human Factors (HF);
Requirements for interoperable total conversation services

2 ETSI ES 204 009 V1.1.1 (2025-08)

Reference
DES/HF-00301559
Keywords
accessibility, HF, ICT, procurement, relay, service,
total conversation
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ETSI
3 ETSI ES 204 009 V1.1.1 (2025-08)
Contents
Intellectual Property Rights . 7
Foreword. 7
Modal verbs terminology . 7
1 Scope . 8
2 References . 8
2.1 Normative references . 8
2.2 Informative references . 9
3 Definition of terms, symbols and abbreviations . 13
3.1 Terms . 13
3.2 Symbols . 13
3.3 Abbreviations . 14
4 Total conversation service: General characteristics and usage scenarios. 14
4.1 General functionality of total conversation services . 14
4.1.1 Type of service . 14
4.1.2 Provided media . 15
4.1.2.1 General about provided media . 15
4.1.2.2 Real-time text . 15
4.1.2.3 Video . 15
4.1.2.4 Voice . 15
4.1.2.5 Other components in the session . 15
4.2 Usage scenarios: Typical communication situations . 16
4.2.1 Communication with any other users . 16
4.2.1.1 General . 16
4.2.1.2 Multimodal communication . 16
4.2.1.3 Multiparty communication . 16
4.2.1.4 Communication across different services . 17
4.2.2 Communication supported by relay services and transcription functions . 17
4.2.3 Using total conversation for emergency communication . 17
4.2.4 Usage with assistive technologies . 18
4.2.4.1 General on assistive technologies . 18
4.2.4.2 Accessibility of alerts in communication initialization . 18
4.2.4.3 Accessibility of voice communication by assistive technologies . 18
4.2.4.4 Accessibility of real-time text communication by assistive technologies . 19
5 Requirements for total conversation service provision . 19
5.1 General . 19
5.2 Performance requirements on media . 20
5.2.1 Real-time text . 20
5.2.1.1 End-to-end delay and smoothness of presentation. 20
5.2.1.2 Reliability . 20
5.2.1.3 Character representation and editing . 20
5.2.1.4 Other performance related aspects of RTT . 21
5.2.2 Video . 21
5.2.2.1 End-to-end delay of video . 21
5.2.2.2 Smoothness of motion reproduction . 21
5.2.2.3 Spatial resolution and sharpness . 21
5.2.2.4 Evaluation of video quality . 21
5.2.3 Voice . 21
5.2.3.1 End to end delay for voice communication . 21
5.2.3.2 Frequency range of voice communication . 22
5.2.4 Synchronization of multiple communication media . 22
5.2.4.1 General . 22
5.2.4.2 Voice and video synchronization . 22
5.2.4.3 Subtitling synchronization . 22
5.2.5 Multiparty considerations . 23
ETSI
4 ETSI ES 204 009 V1.1.1 (2025-08)
5.2.5.1 Video . 23
5.2.5.2 Voice . 23
5.2.5.3 Real-time text . 23
5.3 Service provisioning . 24
5.3.1 System architecture (informative) . 24
5.3.1.1 Functional elements . 24
5.3.1.2 Typical communication actions . 25
5.3.1.2.1 Communication between user equipment within a service . 25
5.3.1.2.2 Communication between user equipment of different services . 25
5.3.1.2.3 Communication between user equipment of different technologies . 25
5.3.1.2.4 Addressing . 26
5.3.1.2.5 Communication with relay service support . 26
5.3.1.2.6 Aspects of total conversation user equipment important for emergency communications . 26
5.3.2 Subscription of user equipment for use in a service . 27
5.4 Communication protocols .
...