1、CCITT RECMN*D-3 92 m 4862573 0572894 784 m INTERNATIONAL TELECOMMUNICATION UN ION CCITT THE INTERNATIONAL TELEGRAPH AND TELEPHONE CONSULTATIVE COMMITTEE GENERAL TARIFF PRINCIPLES CHARGING AND ACCOUNTING IN INTERNATIONAL TELECOMMUNICATIONS SERVICES D.3 PRINCIPLES FOR THE LEASE OF ANALOGUE INTERNATION
2、AL CIRCUITS FOR PRIVATE SERVICE Recommendation D.3 Geneva, 1992 CCITT RECMN*Dm3 92 LIB62591 0572895 610 W - INTERNATIONAL TELECOMMUNICATION UNION CCITT THE INTERNATIONAL TELEGRAPH AND TELEPHONE CONSULTATIVE COMMITTEE GENERAL TARIFF PRINCIPLES CHARGING AND ACCOUNTING IN INTERNATIONAL TELECOMMUNICATIO
3、NS SERVICES D.3 PRINCIPLES FOR THE LEASE OF ANALOGUE INTERNATIONAL CIRCUITS FOR PRIVATE SERVICE Recommendation D.3 I Geneva, 1992 CCITT RECMN*D*3 72 4862573 057287b 557 = FOREWORD The CCIT (the International Telegraph and Telephone Consultative Committee) is a permanent organ of the International Te
4、lecommunication Union (ITU). CCIT 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 Plenary Assembly of CCIT which meets every four years, establishes the topics for stud
5、y and approves Recommendations prepared by its Study Groups. The approval of Recommendations by the members of CCIT between Plenary Assemblies is covered by the procedure laid down in CCIT Resolution No. 2 (Melbourne, 1988). Recommendation D.3 was prepared by Study Group III and was approved under t
6、he Resolution No. 2 procedure on the 16th of June 1992. CCIT NOTE In this Recommendation, the expression “Administration” is used for conciseness to indicate both a telecommunication Administration and a recognized private operating agency. O ITU 1992 All rights reserved. Unless otherwise specified,
7、 no part of this publication 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. CCITT RECMN*D-3 92 4Bb259L 0572897 493 Recommendation D.3 PRINCIPLES FOR THE LEASE OF ANALOGUE) INTERNAT
8、IONAL mcurrs FOR PRTYATE SERVICE Preamble This Recommendation which should be applied in conjunction with the provisions of Recommendation D.l sets out the principles intended for application to analogue) telecommunication circuits leased for private service. 1 Scope of Recommendation This Recommend
9、ation covers the lease of: - - - telegraph-type circuits; - Digitized channels; - high frequency radio circuits; - special quality leased circuits. Principles for the lease of digital circuits are contained in Recommendation D.8. telephone-type circuits of standard bandwidth, 48 kHz wideband analogu
10、e circuits; 2. Telephone-type circuits of a standard bandwidth Telephone-type circuits of a standard bandwidth are suitable for a number of applications, e.g.: a) speech; b) record communications, including telegraphy, facsimile telegraphy, VF telegraphy and data; c) alternate or simultaneous voice/
11、record, or recordrecord communications, in so far as combinations thereof are technically feasible. In principle, charges should not depend on the application used. 3 48 kHz wideband analogue circuits A rational relationship should be established between the tariffs applicable to the standard teleph
12、one-type circuits and 48 kHz circuits. This relationship should take into consideration economies resulting from new or advanced technology, and other rate making factors. 4 Telegraph-type circuits particularly in relations with developing countries. The lease of telegraph-type circuits should be pr
13、ovided to meet the reasonable demand of customers, Including the use of digitized leased channels and telegraph type circuits. Recommendation D.3 1 CCITT RECMN*D.3 92 W 4862593 0572898 32T The standard modulation rate is 50 baud. Where technical characteristics permit, and subject to agreement - qua
14、rter character rate: - half character rate; - 75bauds; - 100bauds; - 200bauds; - 300bauds. A rational relationship should be established between the tariffs applicable to the standard telephone-type circuits and telegraph-type circuits. This relationship should take into consideration economies resu
15、lting from new or advanced technology, and other rate making factors, for example the availability of unused capacity on specific routes. between Administrations, the following modulation rates may also be provided: 5 Digitized channels may consist of both analogue and digitai sections. A digitized
16、leased channel is one which is set up on a circuit equipped to transmit digitai signals. This circuit Circuits having the foliowing standard classes of basic bit rates may be provided by Administrations: - 1200 bids: - 2400 bids; - 4800bids; - 9600bids. Where technical characteristics permit and sub
17、ject to agreement between the Administrations concerned, circuits at bit rates not mentioned above may be offered. A rational relationship should be established between the tariffs applicable to the standard telephone-type circuits and digitized channels. This relationship should take into considera
18、tion economies resulting from new or advanced technology, and other rate making factors. 6 exceptions to the principles recommended for leased circuits in this Recommendation. Leased circuits provided by high frequency radio In the case of leased circuits provided by high frequency radio, Administra
19、tions may elect to make 7 Leased circuits having special qualities For the lease of a circuit having special qualities (for example, circuits meeting the technical specification set out in Recommendations M.1020 and M.1025), an additional monthly flat-rate charge may be applied by terminal Administrations to take into account the cost of providing and maintaining the circuit with the special qualities required. 2 Recommendation D.3
