1、 International Telecommunication Union ITU-T Series GTELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Supplement 43(06/2010) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Transport of IEEE 10GBASE-R in optical transport networks (OTN) ITU-T G-series Recommendations Supplement
2、 43 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 ANALOGUE CARRIER-TRANSMISSION SYSTEMS G.200G.299 INDIVIDUAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEP
3、HONE 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 COORDINATION OF RADIOTELEPHONY AND LINE TELEPHONY G.450G.499 TRANSMISSION MEDIA AND OPTICAL SYSTEMS CHARAC
4、TERISTICS G.600G.699 DIGITAL TERMINAL 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
5、GENERIC ASPECTS G.7000G.7999 PACKET OVER TRANSPORT ASPECTS G.8000G.8999 ACCESS NETWORKS G.9000G.9999 For further details, please refer to the list of ITU-T Recommendations. G series Supplement 43 (06/2010) i Supplement 43 to ITU-T G-series Recommendations Transport of IEEE 10GBASE-R in optical trans
6、port networks (OTN) Summary Supplement 43 to ITU-T G-series Recommendations describes several approaches for transport of 10G LAN PHY over SDH and OTN transport networks. As some of these approaches use rates, formats and mappings that are not defined in ITU-T Recommendations, this supplement analys
7、es various attributes of the different approaches to provide guidance regarding their applicability to different network contexts. This supplement relates to Recommendations ITU-T G.872, ITU-T G.709/Y.1331, ITU-T G.798, ITU-T G.707/Y.1322, ITU-T G.8010/Y.1306, ITU-T G.8012/Y.1308, ITU-T G.959.1 and
8、ITU-T G.696.1. History Edition Recommendation Approval Study Group 1.0 ITU-T G Suppl. 43 2006-11-10 15 2.0 ITU-T G Suppl. 43 2008-02-22 15 3.0 ITU-T G Suppl. 43 2008-12-12 15 4.0 ITU-T G Suppl. 43 2010-06-11 15 ii G series Supplement 43 (06/2010) FOREWORD The International Telecommunication Union (I
9、TU) 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 technical, operating and tariff questions and is
10、suing 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 which, in turn, produce Recommendations on these t
11、opics. 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 and IEC. NOTE In this publication, the expression
12、“Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this publication is voluntary. However, the publication may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and co
13、mpliance with the publication 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 words does not suggest that compliance with the publication is r
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16、plementers 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 2010 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior wri
17、tten permission of ITU. G series Supplement 43 (06/2010) iii CONTENTS Page 1 Scope 1 2 References. 1 3 Definitions 2 4 Abbreviations and acronyms 2 5 Conventions 3 6 Standard mappings 3 6.1 10GBASE-W (WAN PHY) via STM-64 . 3 6.2 GFP-F mapping of 10GBASE-R (LAN PHY) payload only into OPU2 . 3 7 Non-s
18、tandard mappings 3 7.1 Bit transparent mapping of 10GBASE-R signal into OPU2e 4 7.2 Bit transparent mapping of 10GBASE-R signal into OPU1e 4 7.3 ITU-T G.709 bit-rate compliant information transparent transport of payload and preamble . 4 8 Characteristics of alternative mappings 4 8.1 ITU-T G.709 bi
19、t-rate compliant . 6 8.2 Inter-domain/intra-domain interfaces . 6 8.3 Timing and synchronization . 6 8.4 Optical characteristics 6 8.5 Multiplexing, multi-service 6 8.6 Transparency 7 8.7 BER monitoring 8 9 Multiplexing four ODU2e signals into ODU3e 8 9.1 Asynchronous bit-transparent mapping of 4 x
20、ODU2e signals into OPU3e1 8 9.2 Asynchronous generic mapping of four ODU2e signals into OPU3e2 16 G series Supplement 43 (06/2010) 1 Supplement 43 to ITU-T G-series Recommendations Transport of IEEE 10GBASE-R in optical transport networks (OTN) 1 Scope This supplement describes different approaches
21、for transport of 10GBASE-R signals in optical transport networks via an ODU2 or non-standard ODU2-like frame format (i.e., rates, formats and mappings that are not defined in ITU-T Recommendations). This supplement includes descriptions related to multiplexing the non-standard ODU2-like structures i
22、nto ODU3-like signals. Different attributes of the varying solutions are described to help provide guidance on which approaches are appropriate to which network contexts. Including a currently non-standard mapping in this supplement does not preclude considering that mapping for standardization at a
23、 future date. 2 References ITU-T G.694.1 Recommendation ITU-T G.694.1 (2002), Spectral grids for WDM applications: DWDM frequency grid. ITU-T G.696.1 Recommendation ITU-T G.696.1 (2005), Longitudinally compatible intra-domain DWDM applications. ITU-T G.707 Recommendation ITU-T G.707/Y.1322 (2007), N
24、etwork node interface for the synchronous digital hierarchy (SDH). ITU-T G.709 Recommendation ITU-T G.709/Y.1331 (2009), Interfaces for the Optical Transport Network (OTN). ITU-T G.798 Recommendation ITU-T G.798 (2006), Characteristics of optical transport network hierarchy equipment functional bloc
25、ks. ITU-T G.870 Recommendation ITU-T G.870/Y.1352 (2004), Terms and definitions for optical transport networks (OTN). ITU-T G.872 Recommendation ITU-T G.872 (2001), Architecture of optical transport networks. ITU-T G.959.1 Recommendation ITU-T G.959.1 (2006), Optical transport network physical layer
26、 interfaces. ITU-T G.7041 Recommendation ITU-T G.7041/Y.1303 (2008), Generic framing procedure (GFP). ITU-T G.8001 Recommendation ITU-T G.8001/Y.1354 (2006), Terms and definitions for Ethernet frames over Transport (EoT). ITU-T G.8010 Recommendation ITU-T G.8010/Y.1306 (2004), Architecture of Ethern
27、et layer networks. ITU-T G.8012 Recommendation ITU-T G.8012/Y.1308 (2004), Ethernet UNI and Ethernet NNI. ITU-T G.8251 Recommendation ITU-T G.8251 (2001), The control of jitter and wander within the optical transport network (OTN). 2 G series Supplement 43 (06/2010) IEEE 802.3 IEEE 802.3-2005, Infor
28、mation Technology Telecommunications and information exchange between systems Local and metropolitan area networks Specific requirements Part 3: Carrier Sense Multiple Access with Collision Detection (CSMA/CD) access method and physical layer specifications. 3 Definitions None. 4 Abbreviations and a
29、cronyms This supplement uses the following abbreviations and acronyms: CBR10G Constant Bit Rate signal of 9 953 280 kbit/s 20 ppm (see ITU-T G.870) CBR2G5 Constant Bit Rate signal of 2 488 320 kbit/s 20 ppm (see ITU-T G.870) FCS Frame Check Sequence FEC Forward Error Correction GFP Generic Framing P
30、rocedure GMP Generic Mapping Procedure IaDI Intra-Domain Interface (see ITU-T G.870) IPG Inter-Packet Gap IrDI Inter-Domain Interface (see ITU-T G.870) JC Justification Control JOH Justification Overhead MAC Media Access Control MFAS MultiFrame Alignment Signal MSI Multiplex Structure Identifier NJO
31、 Negative Justification Opportunity OCC Optical Channel Carrier with full functionality (see ITU-T G.870) OCCr Optical Channel Carrier with reduced functionality (see ITU-T G.870) ODU Optical Data Unit OH Overhead OPU Optical Payload Unit OTU Optical Transmission Unit PHY Physical layer PJO Positive
32、 Justification Opportunity PT Payload Type SDH Synchronous Digital Hierarchy SFD Start-of-Frame Delimiter SONET Synchronous Optical Network TS Tributary Slot G series Supplement 43 (06/2010) 3 TSOH Time Slot Overhead WAN Wide Area Network 5 Conventions Transmission order: The order of transmission o
33、f information in all the figures in this supplement is first from left to right and then from top to bottom. Within each byte, the most significant bit is transmitted first. The most significant bit (bit 1) is illustrated at the left in all the figures. 6 Standard mappings 6.1 10GBASE-W (WAN PHY) vi
34、a STM-64 IEEE 802.3 has defined a WAN interface for compatibility with SDH/SONET transport. In the Ethernet domain, this interface is supported via a WAN interface sub-layer (clause 50 of IEEE 802.3) that limits the effective data rate of the XGMII from 10 Gbit/s to 9.95328 Gbit/s prior to 64B/66B c
35、oding and insertion in an SDH/SONET format frame. The mapping of this data into the frame of an SDH STM-64 (VC-4-64c) is illustrated in Annex F of ITU-T G.707. Even if the interface provides only the 20 ppm clock accuracy required by clause 50 of IEEE 802.3, rather than SDH clock tolerances (4.6 ppm
36、), this can be transported via ODU2 according to the mapping specified in clause 17.2.2 of ITU-T G.709. 6.2 GFP-F mapping of 10GBASE-R (LAN PHY) payload only into OPU2 A payload information transparent mapping can be performed according to clause 17.4 of ITU-T G.709 using the following process: Term
37、inate (sink) the 64B/66B line code, preamble, SFD and IPG as per IEEE 802.3. Apply GFP-F framing. Encode into an OPU2 according to clause 17.4 of ITU-T G.709. On the assumption that MAC frames do not on average exceed the maximum size specified by IEEE 802.3 (1518 octets excluding the preamble, SFD
38、and IPG), the bit rate required is for a signal that is +100 ppm from the nominal bit rate, approximately 9922968.791 kbit/s. If maximum size jumbo frames are used, the bit rate required for a signal that is +100 ppm from the nominal bit rate is approximately 9995002.399 kbit/s. Note that in the map
39、ping of GFP frames into OPUk specified in clause 17.4 of ITU-T G.709, the entire OPU2 payload area of 9995277 kbit/s is available (i.e., the fixed stuff bytes of the CBR10G mapping are not present). For an OPU2 that is running at the minimum rate of 20 ppm from the nominal value, this is reduced to
40、9995077.058 kbit/s. With standard IEEE 802.3 termination, this mapping can fully transport every ETH_CI traffic unit from a 10GBASE-R signal over an OPU2. Refer to Table V.4 of ITU-T G.7041, where a characterization is given of the MAC rate throughput (not counting overhead) of 10GBASE-R signals ver
41、sus GFP mappings. The MAC rate throughput of a 10GBASE-R interface, assuming a worst case situation of 9618-byte jumbo-frames is 9986502 bit/s. The MAC rate throughput of GFP mapping of the same MAC frames into ODU2 is 9986970 bit/s, which is greater than what is required to carry the entire MAC pay
42、load from a 10GBASE-R signal. 7 Non-standard mappings This means rates, formats and mappings that are not fully defined in ITU-T Recommendations. 4 G series Supplement 43 (06/2010) 7.1 Bit transparent mapping of 10GBASE-R signal into OPU2e This mapping has been moved to clause 17.2.4 of ITU-T G.709.
43、 With this mapping, the resulting OTU-like OTU2e signal must be clocked at a nominal bit rate of 11.0957 Gbit/s, as opposed to the standard OTU2 nominal bit rate of 10.709225316 Gbit/s. 7.2 Bit transparent mapping of 10GBASE-R signal into OPU1e This mapping uses the mapping of a CBR2G5 signal into O
44、PU1, defined in clause 17.2.1 of ITU-T G.709. It has the same attributes as the clause 7.1 mapping above, but since the fixed stuff bytes of the CBR10G mapping are not left free, the overall data rate is somewhat less (11.0491 Gbit/s rather than 11.0957 Gbit/s). As with the clause 7.1 option, the cl
45、ock tolerance of the underlying Ethernet signal (100 ppm) rather than that of a standard OTU2 signal (20 ppm), standard methods for control of jitter and wander according to ITU-T G.8251 do not apply. A unique payload type (PT) shall be specified in the payload structure identifier (PSI). For exampl
46、e, code “0x80“ (reserved code for proprietary use per Table 15-8 of ITU-T G.709 Payload type code points) is to be used. GSup43(08)_F7-1OPU1eClient payload11.0491 Gbit/s(255/238 10.3125)10.3125 Gbit/s(10GbE LAN PHY)OTU1e ODU1e10.3558 Gbit/s 10.3125)(239/238 1 1 1Figure 7-1 Mapping structure without
47、fixed stuffing GSup43(08)_F7-2RowOTUk FEC7 81FAS OTUk OH14 15 16 17 3824 3825OPUk payload4080ColumnOPUkOH1234Figure 7-2 Mapping frame without fixed stuff bytes 7.3 ITU-T G.709 bit-rate compliant information transparent transport of payload and preamble This mapping has been moved to clause 17.4.1 of
48、 ITU-T G.709 and clause 7.9 of ITU-T G.7041. 8 Characteristics of alternative mappings Table 8-1 provides a summary of the characteristics and applicability of each of the different mappings. Further discussion of each of these characteristics is provided in the indicated clauses. Table 8-1 Characte
49、ristics of alternative mappings Mapping Clause 6.1 Clause 6.2 Clause 7.1 Clause 7.2 Clause 7.3 ITU-T G.709 bit-rate compliant (clause 8.1) Yes Yes No No Yes IrDI/IaDI (clause 8.2) Both Both IaDI only IaDI only Both G series Supplement 43 (06/2010) 5 Table 8-1 Characteristics of alternative mappings Mapping Clause 6.1 Clause 6.2 Clause 7.1 Clause 7.2 Clause 7.3 Clock tolerance of client Ethernet signal (clause 8.3)
