ITU-T-Empfehlungen U-Serie


Die U-Serie beschäftigt sich mit Telegraphievermittlung.

General


U.1
Signalling conditions to be applied in the international telexservice

U.2
Standardization of dials and dial pulse generators for theinternational telex service

U.3
Arrangements in switching equipment to minimize the effects offalse calling signals

U.4
Exchange of information regarding signals destined to be usedover international circuits concerned with switched teleprinter networks

U.5
Requirements to be met by regenerative repeaters ininternational connections

U.6
Prevention of fraudulent transit traffic in the fully automaticinternational telex service

U.7
Numbering schemes for automatic switching networks

U.8
Hypothetical reference connections for telex and gentex networks

U.10
Equipment of an international telex position

Specific signalling schemes and interworking between signalling systems


U.11
Telex and gentex signalling on intercontinental circuits usedfor intercontinental automatic transit traffic (type c signalling)

U.12
Terminal and transit control signalling system for telex andsimilar services on international circuits (type D signalling)

U.15
Interworking rules for international signalling systemsaccording to Recommendations U.1, U.11 and U.12

Signalling over radio and multiplexed channels


U.20
Telex and gentex signalling on radio channels (synchronous7-unit systems affording error correction by automatic repetition)

U.21
Operator recall on a telex call set up on a radiotelegraphcircuit

U.22
Signals indicating delay in transmission on calls set up bymeans of synchronous systems with automatic error correction byrepetition

U.23
Use of radiotelegraph circuits with ARQ equipment for fullyautomatic telex calls charged on the basis of elapsed time

U.24
Requirements for telex and gentex operation to be met bysynchronous multiplex equipment described in Recommendation R.44

U.25
Requirements for telex and gentex operation to be met bycode- and speed-dependent TDM systems conforming to RecommendationR.101

Gentex signalling


U.30
Signalling conditions for use in the international gentexnetwork

U.31
Prevention of connection to faulty stations and/or stationlines in the gentex service

Particular signalling facilities


U.40
Reactions by automatic terminals connected to the telex networkin the event of ineffective call attempts or signalling incidents

U.41
changed address interception and call redirection in the telexservice

U.43
Follow-on calls

U.44
Multi-address calls in real time for broadcast purposes in theinternational telex service

U.45
Response to the not-ready condition of the telex terminal

U.46
Interruption of automatic transmission and flow control in theinternational telex service

Radiotelex interworking


U.60
General requirements to be met in interfacing the internationaltelex network with maritime satellite systems

U.61
Detailed requirements to be met in interfacing the internationaltelex network with maritime satellite systems

U.62
General requirements to be met in interfacing the internationaltelex network with the fully automated maritime VHF/UHF radio system

U.63
General requirements to be met in interfacing the internationaltelex network with the maritime "direct printing" system

Interworking between new information services and telex


U.70
Telex service signals for telex to teletex interworking

U.74
Extraction of telex selection information from a calling telexanswerback

U.75
Automatic called telex answerback check

Telex store and forward


U.80
International telex store and forward access from a telexsubscriber

U.81
International telex store and forward - Delivery to telex

Intex service


U.101
Signalling systems for the Intex service (types E and Fsignalling)

U.102
Intex and similar services - Network requirements to effectinterworking between terminals operating at different speeds

Definitions


U.140
Definitions of essential technical terms relating to telegraphswitching and signalling

The international telex service


U.200
The international telex service - General technicalrequirements for interworking

U.201
Interworking between the teletex service and the internationaltelex service

U.202
Technical requirements to be met in providing the internationaltelex service within an integrated services digital network

U.203
Technical requirements to be met when providing real-timebothway communications between terminals of the international telexservice and data terminal equipments on a PSPDN or via the PSTN

U.204
Interworking between the international telex service and thepublic interpersonal messaging service

U.205
Store-and-retrieve facility for the delivery of messages froma terminal of the international telex service to a data terminalequipment which connects to a packet-switched public data network overthe public switched telephone network

U.206
Technical requirements for interworking between theinternational telex service and the videotex service

U.207
Technical requirements to be met for the transfer of messagesbetween terminals of the international telex service and group 3facsimile terminals connected to the PSTN

U.208
The international telex service - Interworking with theINMARSAT C system using one-stage selection

U.210
Intex service Network requirements to effect interworking withthe international telex service

U.220
The international telex service - Technical requirements for astatus enquiry function in an interworking scenario

Supplements to the Series U Recommendations

0-9|A|B|C|D|E|F|G|H|I|J|K|L|M|N|O|P|Q|R|S|T|U|V|W|X|Y|Z|alle

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