1、 International Telecommunication Union ITU-T G.8040/Y.1340TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (09/2005) SERIES G: TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS Ethernet over Transport aspects General aspects SERIES Y: GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL AS
2、PECTS AND NEXT-GENERATION NETWORKS Internet protocol aspects Transport GFP frame mapping into Plesiochronous Digital Hierarchy (PDH) ITU-T Recommendation G.8040/Y.1340 ITU-T G-SERIES RECOMMENDATIONS TRANSMISSION SYSTEMS AND MEDIA, DIGITAL SYSTEMS AND NETWORKS INTERNATIONAL TELEPHONE CONNECTIONS AND
3、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.300G.399 GENERAL CHARACTERISTICS OF INTERNATIONAL CARRIER TELEPHONE SYSTEMS ON RADIO-RELAY OR SATELLITE
4、 LINKS AND INTERCONNECTION WITH METALLIC LINES G.400G.449 COORDINATION OF RADIOTELEPHONY AND LINE TELEPHONY G.450G.499 TRANSMISSION MEDIA CHARACTERISTICS G.600G.699 DIGITAL TERMINAL EQUIPMENTS G.700G.799 DIGITAL NETWORKS G.800G.899 DIGITAL SECTIONS AND DIGITAL LINE SYSTEM G.900G.999 QUALITY OF SERVI
5、CE AND PERFORMANCE GENERIC AND USER-RELATED ASPECTS G.1000G.1999 TRANSMISSION MEDIA CHARACTERISTICS G.6000G.6999 DATA OVER TRANSPORT GENERIC ASPECTS G.7000G.7999 ETHERNET OVER TRANSPORT ASPECTS G.8000G.8999 General aspects G.8000G.8099 MPLS over Transport aspects G.8100G.8199 Quality and availabilit
6、y targets G.8200G.8299 ACCESS NETWORKS G.9000G.9999 For further details, please refer to the list of ITU-T Recommendations. ITU-T Rec. G.8040/Y.1340 (09/2005) i ITU-T Recommendation G.8040/Y.1340 GFP frame mapping into Plesiochronous Digital Hierarchy (PDH) Summary This Recommendation provides the m
7、apping to be used for the transport of GFP frames over PDH at the various hierarchical bit rates defined in ITU-T Rec. G.702. This mapping covers the N 1544 kbit/s, N 2048 kbit/s, N 44 736 kbit/s, and N 34 368 kbit/s signals and is used in conjunction with the frame structures defined in ITU-T Recs
8、G.704 and G.7043/Y.1343. Source ITU-T Recommendation G.8040/Y.1340 was approved on 6 September 2005 by ITU-T Study Group 15 (2005-2008) under the ITU-T Recommendation A.8 procedure. ii ITU-T Rec. G.8040/Y.1340 (09/2005) FOREWORD The International Telecommunication Union (ITU) is the United Nations s
9、pecialized agency in the field of telecommunications. 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 issuing Recommendations on them with a view to standardizing telecommunications
10、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 topics. The approval of ITU-T Recommendations is covered by the procedure laid
11、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 Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunicati
12、on administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure e.g. interoperability or applicability) and compliance with the Recommendation is achieved when all of these mandator
13、y 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 Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTS ITU draws atte
14、ntion 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 concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or other
15、s 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 patents, which may be required to implement this Recommendation. However, implementors are cautioned that this may not represent
16、the latest information and are therefore strongly urged to consult the TSB patent database. ITU 2006 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. ITU-T Rec. G.8040/Y.1340 (09/2005) iii CONTENTS Page 1 Scope
17、1 2 References. 1 3 Definitions 1 4 Abbreviations 1 5 Conventions 1 6 Mapping GFP frames into PDH signals . 2 6.1 Mapping into N 1544 kbit/s 2 6.2 Mapping into N 2048 kbit/s 2 6.3 Mapping into N 44 736 kbit/s . 3 6.4 Mapping into N 34 368 kbit/s . 4 iv ITU-T Rec. G.8040/Y.1340 (09/2005) Introduction
18、 The generic framing procedure (GFP), as defined in ITU-T Rec. G.7041/Y.1303, was developed for transport of data clients over synchronous digital hierarchy (SDH) networks of ITU-T Rec. G.707/Y.1322 and optical transport networks (OTN) of ITU-T Rec. G.709/Y.1331. Interfaces from the plesiochronous d
19、igital hierarchy (PDH) are ubiquitous, especially in the access networks where there is a desire to carry client data signals. GFP has been identified as a suitable technique for mapping data frames into PDH signals of the hierarchies of ITU-T Rec. G.704 as well as the virtually concatenated PDH sig
20、nals as defined in ITU-T Rec. G.7043/Y.1343. ITU-T Rec. G.8040/Y.1340 (09/2005) 1 ITU-T Recommendation G.8040/Y.1340 GFP frame mapping into Plesiochronous Digital Hierarchy (PDH) 1 Scope This Recommendation provides the mapping of GFP-encapsulated data into PDH signals for transport over PDH trails.
21、 The octet-wise mapping into octet-oriented transport containers originally defined for GFP is maintained. 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publ
22、ication, the editions indicated were valid. All Recommendations and other references are subject to revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below. A list of t
23、he currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. ITU-T Recommendation G.702 (1988), Digital hierarchy bit rates. ITU-T Recommendation G.704 (1998), Sync
24、hronous frame structures used at 1544, 6312, 2048, 8448 and 44 736 kbit/s hierarchical levels. ITU-T Recommendation G.832 (1998), Transport of SDH elements on PDH networks Frame and multiplexing structures. ITU-T Recommendation G.7041/Y.1303 (2005), Generic framing procedure (GFP). ITU-T Recommendat
25、ion G.7042/Y.1305 (2004), Link capacity adjustment scheme (LCAS) for virtual concatenated signals. ITU-T Recommendation G.7043/Y.1343 (2004), Virtual concatenation of plesiochronous digital hierarchy (PDH) signals. 3 Definitions This Recommendation does not define any terms. 4 Abbreviations This Rec
26、ommendation uses the following abbreviations: GFP Generic Framing Procedure LCAS Link Capacity Adjustment Scheme PDH Plesiochronous Digital Hierarchy VCAT Virtual Concatenation 5 Conventions The octets of the GFP frames are mapped into the PDH octets in transmission bit order. Specifically, bit 1 of
27、 a GFP octet is the first bit to be transmitted in the PDH octet into which it is mapped. 2 ITU-T Rec. G.8040/Y.1340 (09/2005) 6 Mapping GFP frames into PDH signals 6.1 Mapping into N 1544 kbit/s 6.1.1 Frame and multiframe format The 1544 kbit/s signal payload is typically arranged as 24 octets (i.e
28、., time slots 1 to 24), as illustrated in Figure 6-1a. The multiframe structure for the 24-frame multiframe as described in ITU-T Rec. G.704 shall be used. The first octet following the first framing bit of the multiframe is used to carry the concatenation overhead, as defined in ITU-T Rec. G.7043/Y
29、.1343 and illustrated in Figure 6-1b. This octet is reserved for all values of N, (N = 1.16). For the non-VCAT/LCAS case (which implies one 1544 kbit/s signal), the concatenation overhead octet shall be set to a value of 0x00. Figure 6-1/G.8040/Y.1340 Octet-aligned mapping for GFP into the 1544 kbit
30、/s signal 6.1.2 GFP frame rate adaptation When neither GFP client data frames nor GFP client management frames are available from the GFP source adaptation process, GFP Idle frames shall be inserted in order to perform rate adaptation, filling the server capacity as described in ITU-T Rec. G.7041/Y.
31、1303. 6.1.3 Scrambling of the GFP payload GFP frames are scrambled consistent with ITU-T Rec. G.7041/Y.1303. 6.1.4 GFP frame delineation GFP frame delineation is performed in the manner described in ITU-T Rec. G.7041/Y.1303. 6.2 Mapping into N 2048 kbit/s 6.2.1 Frame and multiframe format The basic
32、frame structure at 2048 kbit/s as described in ITU-T Rec. G.704 shall be used. Time slots 1-31 are used to carry the GFP octets. The multiframe structure for the 16-frame multiframe as described in ITU-T Rec. G.704 shall be used. Time slot 1 of the first frame of the multiframe is used to carry the
33、concatenation overhead, as defined in ITU-T Rec. G.7043/Y.1343 and illustrated in Figure 6-2. This octet is reserved for all ITU-T Rec. G.8040/Y.1340 (09/2005) 3 values of N, (N = 1.16). For the non-VCAT/LCAS case (which implies one 2048 kbit/s signal), the concatenation overhead octet shall be set
34、to a value of 0x00. Figure 6-2/G.8040/Y.1340 Octet-aligned mapping for GFP into the 2048 kbit/s signal 6.2.2 GFP frame rate adaptation When neither GFP client data frames nor GFP client management frames are available from the GFP source adaptation process, GFP Idle frames shall be inserted in order
35、 to perform rate adaptation, filling the server capacity as described in ITU-T Rec. G.7041/Y.1303. 6.2.3 Scrambling of the GFP payload GFP frames are scrambled consistent with ITU-T Rec. G.7041/Y.1303. 6.2.4 GFP frame delineation GFP frame delineation is performed in the manner described in ITU-T Re
36、c. G.7041/Y.1303. 6.3 Mapping into N 44 736 kbit/s 6.3.1 Frame format The multiframe format at 44 736 kbit/s, as described in ITU-T Rec. G.704, shall be used. As illustrated in Figure 6-3, each 44 736 kbit/s subframe (M-subframe) contains 672 bits, which may be regarded as 84 octets, with octets #11
37、, #32, #53 and #74 straddling the F1, F2, F3, and F4 bits, respectively. The first octet (two nibbles) following the first framing bit (X1) of the multiframe is used to carry the concatenation overhead, as defined in ITU-T Rec. G.7043/Y.1343 and illustrated in Figure 6-4. This octet is reserved for
38、all values of N, (N = 1.8). For the non-VCAT/LCAS case (which implies one 44 736 kbit/s signal), the concatenation overhead octet shall be set to a value of 0x00. Figure 6-3/G.8040/Y.1340 Octet structure for the 44 736 kbit/s signal subframe 4 ITU-T Rec. G.8040/Y.1340 (09/2005) Figure 6-4/G.8040/Y.1
39、340 GFP mapping into a 44 736 kbit/s signal frame 6.3.2 GFP frame rate adaptation When neither GFP client data frames nor GFP client management frames are available from the GFP source adaptation process, GFP Idle frames shall be inserted in order to perform rate adaptation, filling the server capac
40、ity as described in ITU-T Rec. G.7041/Y.1303. 6.3.3 Scrambling of the GFP payload GFP frames are scrambled consistent with ITU-T Rec. G.7041/Y.1303. 6.3.4 GFP frame delineation GFP frame delineation is performed in the manner described in ITU-T Rec. G.7041/Y.1303. 6.4 Mapping into N 34 368 kbit/s 6.
41、4.1 Frame format The basic frame and multiframe structure at 34 368 kbit/s as described in ITU-T Rec. G.832 shall be used. As defined in ITU-T Rec. G.7043/Y.1343 and illustrated in Figure 6-5, the first octet following the FA2 octet of the multiframe is used to carry the concatenation overhead. This
42、 octet is reserved for all values of N, (N = 1.8). For the non-VCAT/LCAS case (which implies one 34 368 kbit/s signal), the concatenation overhead octet shall be set to a value of 0x00. Figure 6-5/G.8040/Y.1340 Octet-aligned mapping for GFP into the 34 368 kbit/s signal ITU-T Rec. G.8040/Y.1340 (09/
43、2005) 5 6.4.2 GFP frame rate adaptation When neither GFP client data frames nor GFP client management frames are available from the GFP source adaptation process, GFP Idle frames shall be inserted in order to perform rate adaptation, filling the server capacity as described in ITU-T Rec. G.7041/Y.13
44、03. 6.4.3 Scrambling of the GFP payload GFP frames are scrambled consistent with ITU-T Rec. G.7041/Y.1303. 6.4.4 GFP frame delineation GFP frame delineation is performed in the manner described in ITU-T Rec. G.7041/Y.1303. ITU-T Y-SERIES RECOMMENDATIONS GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PR
45、OTOCOL ASPECTS AND NEXT-GENERATION NETWORKS GLOBAL INFORMATION INFRASTRUCTURE General Y.100Y.199 Services, applications and middleware Y.200Y.299 Network aspects Y.300Y.399 Interfaces and protocols Y.400Y.499 Numbering, addressing and naming Y.500Y.599 Operation, administration and maintenance Y.600
46、Y.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 capabilities and resource management Y.1200Y.1299 Transport Y.1300Y.1399 Interworking Y.1400Y.1499 Quality of service and network perf
47、ormance Y.1500Y.1599 Signalling Y.1600Y.1699 Operation, administration and maintenance Y.1700Y.1799 Charging Y.1800Y.1899 NEXT GENERATION NETWORKS Frameworks and functional architecture models Y.2000Y.2099 Quality of Service and performance Y.2100Y.2199 Service aspects: Service capabilities and serv
48、ice architecture Y.2200Y.2249 Service aspects: Interoperability of services and networks in NGN Y.2250Y.2299 Numbering, naming and addressing Y.2300Y.2399 Network management Y.2400Y.2499 Network control architectures and protocols Y.2500Y.2599 Security Y.2700Y.2799 Generalized mobility Y.2800Y.2899
49、For further details, please refer to the list of ITU-T Recommendations. Printed in Switzerland Geneva, 2006 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-telephone telecommunication services Series G Transmission systems and media, digital systems and networks Series H Audiovisual and multimedia systems Series I Integrated servi
