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.8261/Y.1361 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Amendment 1 (01/2015) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Packet over Transport aspects Synchronization, quality and availabil
2、ity targets SERIES Y: GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS Internet protocol aspects Transport Timing and synchronization aspects in packet networks Amendment 1 Recommendation ITU-T G.8261/Y.1361 (2013) Amendment 1 ITU-T G-SERIES RECOMMENDATIONS T
3、RANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS INTERNATIONAL TELEPHONE CONNECTIONS AND CIRCUITS G.100G.199 GENERAL CHARACTERISTICS COMMON TO ALL ANALOGUE CARRIER-TRANSMISSION SYSTEMS G.200G.299 INDIVIDUAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON METALLIC LINES G.300
4、G.399 GENERAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON RADIO-RELAY OR SATELLITE LINKS AND INTERCONNECTION WITH METALLIC LINES G.400G.449 COORDINATION OF RADIOTELEPHONY AND LINE TELEPHONY G.450G.499 TRANSMISSION MEDIA AND OPTICAL SYSTEMS CHARACTERISTICS G.600G.699 DIGITAL TERMINA
5、L EQUIPMENTS G.700G.799 DIGITAL NETWORKS G.800G.899 DIGITAL SECTIONS AND DIGITAL LINE SYSTEM G.900G.999 MULTIMEDIA 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
6、OVER TRANSPORT ASPECTS G.8000G.8999 Ethernet over Transport aspects G.8000G.8099 MPLS over Transport aspects G.8100G.8199 Synchronization, quality and availability targets G.8200G.8299 Service Management G.8600G.8699 ACCESS NETWORKS G.9000G.9999 For further details, please refer to the list of ITU-T
7、 Recommendations. Rec. ITU-T G.8261/Y.1361 (2013)/Amd.1 (01/2015) i Recommendation ITU-T G.8261/Y.1361 Timing and synchronization aspects in packet networks Amendment 1 Summary Amendment 1 to Recommendation ITU-T G.8261/Y.1361 (2013) provides the following updates: Addition of the network jitter lim
8、its for multilane interfaces consisting of 10 G lanes including 40GBASE-KR4/CR4/SR4/LR4 and 100GBASE-CR10/SR10 and multi-lane interfaces consisting of 25G lanes including 100GBASE-LR4/ER4. History Edition Recommendation Approval Study Group Unique ID* 1.0 ITU-T G.8261/Y.1361 2006-05-22 15 11.1002/10
9、00/8787 1.1 ITU-T G.8261/Y.1361 (2006) Cor. 1 2006-12-14 15 11.1002/1000/9010 2.0 ITU-T G.8261/Y.1361 2008-04-29 15 11.1002/1000/9416 2.1 ITU-T G.8261/Y.1361 (2008) Amd. 1 2010-07-29 15 11.1002/1000/10908 3.0 ITU-T G.8261/Y.1361 2013-08-29 15 11.1002/1000/12015 3.1 ITU-T G.8261/Y.1361 (2013) Amd. 1
10、2015-01-13 15 11.1002/1000/12388 _ * 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.8261/Y.1361 (2013)/Amd.1 (01/2015) FOREW
11、ORD 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 responsible for studying
12、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 the ITU-T study groups wh
13、ich, 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 collaborative basis with ISO an
14、d 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 mandatory provisions (t
15、o 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 requirements. The use of such word
16、s 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 takes no position conce
17、rning 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 property, protected by pa
18、tents, 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 2015 All rights reserved. No part of this pub
19、lication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T G.8261/Y.1361 (2013)/Amd.1 (01/2015) 1 Recommendation ITU-T G.8261/Y.1361 Timing and synchronization aspects in packet networks 1) Clause 9.2.1.3 EEC interface network jitter limits Modify cl
20、ause 9.2.1.3 as shown below: 9.2.1.3 EEC interface network jitter limits See Table 7 for EEC interface network jitter limits. Table 7 EEC interface network jitter limits Interface Reference 2048 kbit/s See ITU-T G.823, clause 6.1: Network limits for output jitter at synchronization interfaces, SEC r
21、equirements (Note 1) 2048 kHz 1544 kbit/s See ITU-T G.824, clause 6.1: Network limits for jitter STM-n See ITU-T G.825, clause 5.1: Network limits for jitter Ethernet (synchronous Ethernet) See Table 7a (Note 2) NOTE 1 Jitter limits are taken from ITU-T G.823, ITU-T G.824 and ITU-T G.825 in order to
22、 allow proper interoperability with SEC based synchronization networks and combined EEC-SEC functions. NOTE 2 In a chain of n (n 20) connected EECs, the accumulated network jitter has to be low enough to allow all involved EECs to meet the output jitter specification at their synchronization outputs
23、 (e.g., 2048 kHz, 2048 kbit/s, 1544 kbit/s). See Figure 16 showing EECs in a chain; see also Annex D. 2 Rec. ITU-T G.8261/Y.1361 (2013)/Amd.1 (01/2015) Table 7a Maximum permissible jitter at synchronous Ethernet network interfaces Interface Measurement bandwidth, 3 dB frequencies Peak-to-peak amplit
24、ude (UIpp) 1 G (Notes 1, 2, 54) 2.5 kHz to 10 MHz 1.5 10 G (Notes 1, 3, 54) 20 kHz to 80 MHz 1.5 25 G (Notes 1, 4, 5, 6) 20 kHz to 200 MHz 3.6 NOTE 1 There is no specific high band jitter requirement for synchronous Ethernet. The relevant IEEE 802.3 jitter requirements shall be met in addition to th
25、e specific synchronous Ethernet wideband jitter requirements specified in this table. NOTE 2 1 G includes 1000BASE-KX, -SX, -LX; multi-lane interfaces are for further study. NOTE 3 10 G includes 10GBASE-SR/LR/ER, 10GBASE-LRM, 10GBASE-SW/LW/EW; and multi-lane interfaces consisting of 10G lanes includ
26、ing 40GBASE-KR4/CR4/SR4/LR4 and 100GBASE-CR10/SR10multi-lane interfaces are for further study. NOTE 4 25G includes multi-lane interfaces consisting of 25G lanes including 100GBASE-LR4/ER4. NOTE 54 1 G (1000BASE-KX, -SX, -LX): 1 UI = 0.8 ns 10 G (10GBASE-SR/LR/ER,-LRM, 40GBASE-KR4/CR4/SR4/LR4, 100GBA
27、SE-CR10/SR10): 1 UI = 96.97 ps 10 G (10GBASE-SW/LW/EW): 1 UI = 100.47 ps 25 G (100GBASE-LR/ER): 1 UI = 37.89 ps NOTE 6 The peak-to-peak jitter amplitude for 25G lanes is increased from 1.5 UI to 3.6 UI, i.e., by a factor of 2.4. To compensate for this increase, the high-pass corner frequency used fo
28、r 10G should first be increased by a factor of 2.5 to take account of the increase in line rate from 10G, and then decreased by a factor of 2.4 to take account of the increase in amplitude. This gives a high-pass corner frequency of 20.833 kHz, which has been rounded down to 20 kHz for convenience;
29、this rounding to a lower value is slightly stricter. Figure 16 shows the reference chain of n (n 20) EECs together with their synchronization outputs. G . 8 2 6 1 - Y . 1 3 6 1 ( 1 3 ) _ F 1 6E E C 1 E E C 2 E E C nS yn c hr on i z a t i oni np ut20 48 k H z o r20 48 k bi t / s o r15 44 k bi t / sET
30、Ys yn c EETYs yn c ES yn c hr on i z a t i onou t pu t20 48 k H z o r20 48 k bi t / s o r15 44 k bi t / sS yn c hr on i z a t i onou t pu t20 48 k H z o r20 48 k bi t / s o r15 44 k bi t / sE H Yt r a f f i cE H Yt r a f f i cE E C 3ETYs yn c ES yn c hr on i z a t i onou t pu t20 48 k H z o r20 48 k
31、 bi t / s o r15 44 k bi t / sFigure 16 EEC chain ITU-T Y-SERIES RECOMMENDATIONS GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS GLOBAL INFORMATION INFRASTRUCTURE General Y.100Y.199 Services, applications and middleware Y.200Y.299 Network aspects Y.300Y.399 I
32、nterfaces and protocols Y.400Y.499 Numbering, addressing and naming Y.500Y.599 Operation, administration and maintenance Y.600Y.699 Security Y.700Y.799 Performances Y.800Y.899 INTERNET PROTOCOL ASPECTS General Y.1000Y.1099 Services and applications Y.1100Y.1199 Architecture, access, network capabili
33、ties and resource management Y.1200Y.1299 Transport Y.1300Y.1399 Interworking Y.1400Y.1499 Quality of service and network performance Y.1500Y.1599 Signalling Y.1600Y.1699 Operation, administration and maintenance Y.1700Y.1799 Charging Y.1800Y.1899 IPTV over NGN Y.1900Y.1999 NEXT GENERATION NETWORKS
34、Frameworks and functional architecture models Y.2000Y.2099 Quality of Service and performance Y.2100Y.2199 Service aspects: Service capabilities and service architecture Y.2200Y.2249 Service aspects: Interoperability of services and networks in NGN Y.2250Y.2299 Enhancements to NGN Y.2300Y.2399 Netwo
35、rk management Y.2400Y.2499 Network control architectures and protocols Y.2500Y.2599 Packet-based Networks Y.2600Y.2699 Security Y.2700Y.2799 Generalized mobility Y.2800Y.2899 Carrier grade open environment Y.2900Y.2999 FUTURE NETWORKS Y.3000Y.3499 CLOUD COMPUTING Y.3500Y.3999 For further details, pl
36、ease refer to the list of ITU-T Recommendations. Printed in Switzerland Geneva, 2015 SERIES OF ITU-T RECOMMENDATIONS Series A Organization of the work of ITU-T Series D General tariff principles Series E Overall network operation, telephone service, service operation and human factors Series F Non-t
37、elephone telecommunication services Series G Transmission systems and media, digital systems and networks Series H Audiovisual and multimedia systems Series I Integrated services digital network Series J Cable networks and transmission of television, sound programme and other multimedia signals Seri
38、es K Protection against interference Series L Construction, installation and protection of cables and other elements of outside plant Series M Telecommunication management, including TMN and network maintenance Series N Maintenance: international sound programme and television transmission circuits
39、Series O Specifications of measuring equipment Series P Terminals and subjective and objective assessment methods Series Q Switching and signalling Series R Telegraph transmission Series S Telegraph services terminal equipment Series T Terminals for telematic services Series U Telegraph switching 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 and next-generation networks Series Z Languages and general software aspects for telecommunication systems
