1、 I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o n ITU-T G.813 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Corrigendum 2 (11/2016) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Digital networks Design objectives for digital networks Timing characteris
2、tics of SDH equipment slave clocks (SEC) Corrigendum 2 Recommendation ITU-T G.813 (2003) Corrigendum 2 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS INTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS G.100G.199 GENERAL CHARACTERISTICS COMMON TO ALL ANALOGU
3、E CARRIER-TRANSMISSION SYSTEMS G.200G.299 INDIVIDUAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON METALLIC LINES G.300G.399 GENERAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON RADIO-RELAY OR SATELLITE LINKS AND INTERCONNECTION WITH METALLIC LINES G.400G.449 COORDIN
4、ATION OF RADIOTELEPHONY AND LINE TELEPHONY G.450G.499 TRANSMISSION MEDIA AND OPTICAL SYSTEMS CHARACTERISTICS G.600G.699 DIGITAL TERMINAL EQUIPMENTS G.700G.799 DIGITAL NETWORKS G.800G.899 General aspects G.800G.809 Design objectives for digital networks G.810G.819 Synchronization, quality and availab
5、ility targets G.820G.829 Network capabilities and functions G.830G.839 SDH network characteristics G.840G.849 Management of transport network G.850G.859 SDH radio and satellite systems integration G.860G.869 Optical transport networks G.870G.879 DIGITAL SECTIONS AND DIGITAL LINE SYSTEM G.900G.999 MU
6、LTIMEDIA QUALITY OF SERVICE AND PERFORMANCE GENERIC AND USER-RELATED ASPECTS G.1000G.1999 TRANSMISSION MEDIA CHARACTERISTICS G.6000G.6999 DATA OVER TRANSPORT GENERIC ASPECTS G.7000G.7999 PACKET OVER TRANSPORT ASPECTS G.8000G.8999 ACCESS NETWORKS G.9000G.9999 For further details, please refer to the
7、list of ITU-T Recommendations. Rec. ITU-T G.813 (2003)/Cor.2 (11/2016) i Recommendation ITU-T G.813 Timing characteristics of SDH equipment slave clocks (SEC) Corrigendum 2 Summary This Corrigendum replaces: The first equation in clause 10.2, numeral a) The second equation in clause 10.2, numeral a)
8、 (above Figure 14). History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T G.813 1996-08-27 13 11.1002/1000/3717 1.1 ITU-T G.813 (1996) Cor. 1 2001-11-29 15 11.1002/1000/5605 2.0 ITU-T G.813 2003-03-16 15 11.1002/1000/6268 2.1 ITU-T G.813 (2003) Cor. 1 2005-06-29 15 11.1002/1000/85
9、26 2.2 ITU-T G.813 (2003) Cor. 2 2016-11-13 15 11.1002/1000/13084 * To access the Recommendation, type the URL http:/handle.itu.int/ in the address field of your web browser, followed by the Recommendations unique ID. For example, http:/handle.itu.int/11.1002/1000/11830-en. ii Rec. ITU-T G.813 (2003
10、)/Cor.2 (11/2016) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is re
11、sponsible 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 Assembly (WTSA), which meets every four years, establishes the topics for study by th
12、e ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collabor
13、ative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain
14、mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirement
15、s. The use of such words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTSITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU
16、takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had not received notice of intellectual pr
17、operty, protected by patents, which may be required to implement this Recommendation. However, implementers are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2017 All rights reserv
18、ed. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T G.813 (2003)/Cor.2 (11/2016) 1 Recommendation ITU-T G.813 Timing characteristics of SDH equipment slave clocks (SEC) Corrigendum 2 1) Clause 10.2, Long-term phase trans
19、ient response (Holdover) 1.1) Replace the following text and equation in clause 10.2, numeral a): When a SEC loses its reference, it is said to enter the holdover state. The Phase Error, T, at the output of the SEC relative to the input at the moment of loss of reference should not, over any period
20、of S 15 s, exceed the following limit: T(S) = (a1 + a2) S + 0.5 b S2 + c ns With: When an SEC loses all its references, it enters the holdover state. The phase error, T, at the output of the SEC relative to the input at the moment of loss of reference should, over any period S 15 s, meet the followi
21、ng: cbSSaaST 221 5.0)( ns 1.2) Replace the second equation in clause 10.2, numeral a) (above Figure 14) with: ns2)( 21 cSbSaSTPrinted in Switzerland Geneva, 2017 SERIES OF ITU-T RECOMMENDATIONS Series A Organization of the work of ITU-T Series D Tariff and accounting principles and international tel
22、ecommunication/ICT economic and policy issues Series E Overall network operation, telephone service, service operation and human factors Series F Non-telephone telecommunication services Series G Transmission systems and media, digital systems and networks Series H Audiovisual and multimedia systems
23、 Series I Integrated services digital network Series J Cable networks and transmission of television, sound programme and other multimedia signals Series K Protection against interference Series L Environment and ICTs, climate change, e-waste, energy efficiency; construction, installation and protec
24、tion of cables and other elements of outside plant Series M Telecommunication management, including telecommunication network management and network maintenance Series N Maintenance: international sound programme and television transmission circuits Series O Specifications of measuring equipment Ser
25、ies P Telephone transmission quality, telephone installations, local line networks Series Q Switching and signalling, and associated measurements and tests Series R Telegraph transmission Series S Telegraph services terminal equipment Series T Terminals for telematic services Series U Telegraph swit
26、ching Series V Data communication over the telephone network Series X Data networks, open system communications and security Series Y Global information infrastructure, Internet protocol aspects, next-generation networks, Internet of Things and smart cities Series Z Languages and general software aspects for telecommunication systems
