ITU-T U 205-1993 Store-and-Retrieve Facility for the Delivery of Messages from a Terminal of the International Telex Service to a Data Terminal Equipment Which Connects to a Packet Swi.pdf

1、I NTERNATIONAL TELECOMMUN ICATION UN ION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU TELEGRAPH SWITCHING INTERNATIONAL TELEX SERVICE U205 (03/93) STORE-AN D-RETRI EVE FACILITY FOR THE DELIVERY OF MESSAGES FROM A TERMINAL OF THE INTERNATIONAL TELEX SERVICE TO A DATA TERMINAL EQUIPMENT WHICH

2、 CONNECTS TO A NETWORK OVER THE PUBLIC SWITCHED TELEPHONE NETWORK PACKET-SWITCHED PUBLIC DATA ITU-T Recommendation U.205 (Previously “CCITT Recommendation”) ITU-T RECMN+U=205 93 E 48b259L 0584353 33T FOREWORD The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of the Intern

3、ational Telecom- munication Union. The ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Conference (WTSC), which meets ever

4、y four years, established the topics for study by the ITU-T Study Groups which, in their turn, produce Recommendations on these topics. ITU-T Recommendation U.205 was prepared by the ITU-T Study Group IX (1988-1993) and was approved by the WTSC (Helsinki, March 1-12, 1993). NOTES 1 As a consequence

5、of a reform process within the International Telecommunication Union (ITU), the CCITT ceased to exist as of 28 February 1993. In its place, the ITU Telecommunication Standardization Sector (ITU-T) was created as of 1 March 1993. Similarly, in this reform process, the CCIR and the IFRB have been repl

6、aced by the Radiocommunication Sector. In order not to delay publication of this Recommendation, no change has been made in the text to references containing the acronyms “CCITT, CCIR or IFRB” or their associated entities such as Plenary Assembly, Secretariat, etc. Future editions of this Recommenda

7、tion will contain the proper terminology related to the new ITU structure. 2 telecommunication administration and a recognized operating agency. In this Recommendation, the expression “Administration” is used for conciseness to indicate both a O ITU 1994 All rights reserved. No part of this publicat

8、ion may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the ITU. Recommendation U.205 STORE-AND-RETRIEVE FACILITY FOR THE DELIVERY OF MESSAGES FROM A TERMINAL OF THE INTERNATIONAL TELEX SERVICE

9、TO A DATA TERMINAL EQUIPMENT WHICH CONNECTS TO THE PUBLIC SWITCHED TELEPHONE NETWORK A PACKET-SWITCHED PUBLIC DATA NETWORK OVER (Helsinki, 1993) The CCIT, considering (a) network via a dial-up connection across the public switched telephone network; the increasing number of data terminal equipments

10、which make connection to a packet-switched public data (b) the world-wide availability of the telex service; (cl network and a packet-switched public data network is provided; that Recommendation F.83 defines the service principles to be followed when intenvorking between the telex (d) equipments in

11、terwork with telex terminals for the purpose of exchanging messages; that Recommendation U.203 describes, inter alia, the technical procedures to be followed when data terminal (e which could be used by a telex terminal for the purpose of recall, that those DTEs which connect to the PSPDN over the P

12、STN may not possess a unique data network address and recognizing that it is desirable to allow telex subscribers who receive messages from such DTEs reply in a standardized manner, unanimously declares the following views: (1) delivery of messages from telex subscribers to DTEs which connect to a P

13、SPDN via the PSTN and which do not possess a unique data network address for use by the telex subscriber for the purpose of recall shall be by means of a device to be known as a “telex mailbox”; (2) country in which the DTE is located; the telex mailbox shall be assigned a telex number that is part

14、of the telex national numbering plan of the (3) established using normal telex procedures as described in the relevant Series-F, -S and -U Recommendations; a call from the international telex network to the telex mailbox for the purpose of depositing a message shall be (4) the answerback to be retur

15、ned from the telex mailbox in response to any received WRU signal (ITA2 combination 30 plus combination 4) shall be formatted in accordance with Recommendation F.74. The received WRU signal should not be stored in the mailbox; (5) mode) shall preferably be in accordance with Recommendation S.22; the

16、 response of the telex mailbox to any received “Bell” signal (ITA2 combination number 10 in figure-shift (6) their occurrence in order to replicate the message as it appears at the originating telex terminal; all received and transmitted characters (e.g. answerback codes) shall be stored in the mail

17、box in the order of (7) the dimensioning of the telex mailbox shall be consistent with the Quality of Service requirements of the international telex service, and in particular the provisions of Recommendation F.60 and Recommendation U. 1 regarding availability; Recommendation U.205 (03/93) 1 ITU-T

18、RECMN*U.205 93 W 4862591 0584355 102 W (8) basis; (9) to a receive-only telex terminal. In particular, a telex mailbox should be capable of emulating a terminating telex terminal in the following way: the telex service shall be deemed to terminate at the telex mailbox, the system operating on a stor

19、e-and-retrieve from the point of view of the telex network, the telex mailbox shall behave in all respects in a manner similar - It should be capable of designation as a multi-line hunting group. For example, this may be necessary either to increase the number of possible simultaneous terminating ca

20、lls to the mailbox or as a means of increasing storage capacity. Should the directory number of the telex mailbox be changed, or diversion to another telex number be in place, then it should be possible to assign either the NCH or RDI condition in accordance with Recommendation U.4 1. It shall be po

21、ssible to assign the ABS condition to the directory number of the telex mailbox. It shall be possible to include a telex mailbox in a list of telex addresses forming a broadcast call. It shall be possible for the originating telex subscriber to deliver a message to a telex mailbox via a SFU. - - - -

22、 the telex mailbox may be located in either the telex network or the public data network of the destination (10) country. The choice is considered to be a national matter; (1 1) network, on a store-and-retrieve basis, shall be in accordance with Recommendation U.206; (12) (13) delivery of messages f

23、rom telex terminals to Videotex terminals connected to the public switched telephone the method employed by the DTE user to retrieve messages from his telex mailbox is a national matter; the following items are left for further study: - - informing the originating telex subscriber that the message which he deposited has been “read”; informing the DTE user that a message awaits in his telex mailbox. 2 Recommendation U.205 (03/93)