7-18 September 2020
ITU-T Study Group 15
Networks, Technologies and Infrastructures for Transport, Access and Home
Study Group 15 held its sixth meeting of the 2017-2020 study period as a fully virtual meeting from 7-18 September 2020, attended by 353 delegates representing 26 countries.
The meeting received 296 contributions and 420 TDs, an expected decrease in contributions from the previous meeting given the reduced meeting time available in a virtual format, and the request of all delegates to focus contribution on work items intended for consent or agreement in this meeting. The meeting observed the 12-day contribution deadline of Recommendation ITU-T A.1, and all of the contributions to this meeting were submitted using Direct Document Posting (DDP).
SG15 consented 52 texts (10 new and 17 revised Recommendations, 22 Amendments, and 3 Corrigenda), and agreed one technical paper, three new and three revised Supplements, one Appendix, and two revised Implementers’ Guides.
Given the current COVID-19 situation, all interregnum activities prior to the next SG15 plenary have been planned as virtual, consisting of 77 single-day or multiple-day virtual meetings. A procedure was defined for authorizing the conversion of some of these virtual meetings to physical meetings should face-to-face meetings become feasible prior to the next plenary of SG15.
In fulfilling its lead study group responsibilities, SG15 revised the Access Network Transport (ANT) standards overview and work plan, the Home Network Transport (HNT) Standards Overview and Work Plan, and the Optical Transport Networks and Technologies (OTNT) standardization work plan. No update was needed to the Smart Grid standards overview and work plan, which no longer requires active coordination.
SG15 finalized inputs to TSAG regarding WTSA-20 preparation, including draft SG15-related updates to WTSA Resolution 2 (regarding study group responsibility and mandates), and draft text of 13 study questions proposed by SG15 for the 2021-2024 study period.
Executive reports from WP Chairmen
WP1/15 – Transport aspects of access, home and smart grid networks
WP1 Chairman: Tom Starr; WP1 Vice-Chairman: Ian Horsley
The suite of new MGfast Recommendations consented at this meeting specify access transmission over telephone wires, CAT 5 and 6 wires, and coax cables at bit rates up to 10 Gb/s with sub-millisecond latency.
Q1/15 met for one day, updating the Access Network Transport (ANT) Standards Overview and Work Plan documents. The Home Network Transport (HNT) Standards Overview and Work Plan document was revised. The list of certification and interoperability activities for WP1/15 Recommendations was updated.
Q2/15 met for seven days, working on Passive Optical Networks (PON), preparing five texts for consent and two for agreement. Work progressed on the TC layer for the high speed PON series of Recommendations.
Q4/15 met for eight days, working on access via metallic conductors, focusing on G.fast and the next-generation MGfast. Five Recommendations were prepared for consent, including the new MGfast Recommendation addressing transmission of up to 10 Gbit/s over metallic conductors.
Q18/15 met for five days, working on the G.hn family of Recommendations, free space optical networking, and related projects. Five texts were prepared for consent, and one Technical Paper for agreement.
The WP1/15 Question texts were reviewed and updated.
WP2/15 – Optical technologies and physical infrastructures
WP2 Chairman: Noriyuki Araki; WP2 Vice-Chairman: Peter Stassar
WP2/15 made good progress on the development of a number of Recommendations and produced three new and six revised Recommendations for consent, as well as a new supplement for agreement at this meeting. WP2 produced one liaison statement and updated its work programme including one new work item. WP2 also scheduled eight interim e-meetings and a number of correspondence activities to progress the work.
Q5/15 worked on characteristics and test methods of optical fibres and cables, and consented the revision of G.650.1, which revised an alternative test method for “Spectral attenuation modelling” to consider applicability of fewer predictor wavelengths for spectral attenuation modelling. Q5 made progress on the new work item for the technical report on optical fibre, cable and components for space division multiplexing transmission.
Q6/15 consented the revised G.672, which specifies new optical transfer parameters for multi-degree reconfigurable optical add/drop multiplexer (MS-ROADM) network element. In conjunction with this revision, Q6 consented the revised G.694.1 to change definitions of relevant terms. Q6 also agreed to start a new work item for draft new Recommendation G.owdm, which deals with optical interface specifications for 25 Gbit/s, 12 channels for an O-band WDM system.
Q8/15 consented the draft new Recommendation G.977.1, which describes transverse compatibility for repeatered optical fibre submarine cable systems, and the revisions of G.971 and G.972 related to general features and definitions of optical submarine cable systems.
Q16/15 worked on optical physical infrastructures and consented the draft new Recommendation L.111 (ex L.oha), Optical fibre cables for in-home applications, and the revised L.151, which deals with the construction and operation of optical ground wire cable. Q16 finalized the new Supplement L suppl.crg for guidance for establishing new optical fibre cable Recommendations under cooperation and harmonization with related standardization bodies.
Q17/15 worked on maintenance and operation of optical fibre cable networks and consented the draft new Recommendation L.330, which deals with Telecommunication infrastructure facility management. Q17 also made good progress on the new draft Recommendation dealing with cable identification for construction and maintenance of optical fibre cable networks.
WP3/15 – Transport network characteristics
WP3 Chairman: Malcolm Betts; WP3 Vice-Chairman: Glenn Parsons
- In support of IMT‑2020/5G transport Q12/15 consented G.8310 “Functional architecture for the metro transport network" and Q11/15 consented G.8312 “Interfaces for the metro transport network". Future work on MTN includes Recommendation on equipment, protection, management and synchronization.
- Work in the enhancement of the OTN Recommendations continued, including a Recommendations on FEC and secure transport.
- Amendments to G.807 (media architecture) and OTN architecture were consented.
- Q13/15 made good progress on several aspects including the analysis of timing performance with the use of higher accuracy clocks for IMT-2020 fronthaul networks.
- Q14/15 is continuing to work in cooperation with IEEE 802.1, IEEE 802.3, ONF, MEF, BBF, and IETF to provide consistent information models and YANG data models for Ethernet
Q10/15 consented revised G.8011 (Ethernet service characteristics) bringing it up in alignment with the latest MEF standards on Carrier Ethernet. Q10/15 also consented revised G.8112 (MPLS-TP interfaces), which together with G.8110.1 Amd.1, supersedes G.8101 (MPLS-TP terms and definitions). Implementers' Guides were agreed for G.8101 and for G.8001 (Ethernet terms and definitions). Work continued on revising G.8012 (Ethernet UNI and NNI) and G.8021 (Ethernet equipment) to supersede G.8012.1 and G8021.1 and to simplify these recommendations via direct referencing of relevant mechanisms specified in non-ITU-T standards. Significant progress was made towards anticipated consent in July 2021 and a series of three E-meetings was approved to continue this work. Future work is also planned towards January 2022 consent of G.8121 Amd.1 (MPLS-TP equipment) to allow MPLS-TP packets to be encapsulated into OPUflex using Idle Mapping Procedure.
Q11/15 made significant progress on many topics, with one new Recommendation consented, two new Supplements agreed, and revisions, amendments or corrigenda consented or agreed for six other Recommendations and Supplements. In the area of transport for 5G, new Recommendation G.8312 on interfaces for metro transport networks was consented and new Supplement G.Sup.mtn-migration was agreed. In the area of long reach interfaces for OTN, a revision to G.709.3 was consented, which adds a FEC for 450 km applications. The initial portion of the Q11 OTN secure transport work was consented with “FlexOsec" as part of the G.709.1 amendment. Multiple updates were made in amendments to G.709 and G.798. A revision to G.Sup58 was agreed, adding 112G electrical lanes for MFIs. New Supplement G.Sup.sub1G was agreed, which describes a method for aggregation of sub-1G services at the edge of an OTN network, based on an SDH-type structure. Due to the very large number of incoming contributions, it was necessary to defer those not addressed at this meeting to be the subjects of the first of three Q11 interregnum meetings. These topics include an amendment to G.8023, new work proposals for OTN and FlexO, and work on a new switched path layer network for carrying sub-1G clients over OTN (G.osu). Q11 intends to hold two additional interregnum meetings to continue work on these and other topics.
Q12/15 consented a new Recommendation G.8310 (“Functional architecture for the metro transport network") that was developed in close collaboration with Q11/15. Metro Transport Network introduces two new connection-oriented layers. An Amendment was completed on G.807 (Generic functional architecture of the optical media network) through collaboration with Q6/15 and clarifies the boundary to the media layer. A corresponding Amendment to G.872 was made to reflect G.807 updates. Progress continued on management and control Recommendations (G.7701, G.7702, and G.7703) in cooperation with Q14/15 and an Amendment was consented to G.7701 (Common aspects).
The Optical Transport Networks & Technologies Standardization Workplan was updated using incoming liaisons from other SDOs. Issue 28 was produced at this meeting and liaised to many SDOs.
A correspondence activity is planned for G.8010 Am. 3 with an eMeeting. A second correspondence activity is planned for G.7702 and G.7703 with three eMeetings.
Q13/15 consented several Recommendations making good progress at this meeting. G.8261 Amd2 (Timing and synchronization aspects in packet networks) and Amd1 to G.8271.1 (Network limits for time synchronization in packet networks with full timing support from the network) were consented with new network limits and guidelines for use in fronthaul networks.
The PTP profiles G.8275.1 and G.8275.2 were amended (Amd1) including new optional features that can be used to supervise the PTP network. G.8275 (Architecture and requirements for packet-based time and phase delivery) was revised to align with the new version of G.8275.1 and G.8275.2 and to capture earlier agreements (e.g., coherent PRTC deployment scenarios).
G.8273.2 (Timing characteristics of telecom boundary clocks and telecom time slave clocks for use with full timing support from the network) was revised with improvements on the performance estimation for a pair of boundary clocks (particularly important in defining the performance of access technologies), and with new requirements (relative time error) for IMT‑2020/5G fronthaul applications.
G.8273.3 (Timing characteristics of telecom transparent clocks for use with full timing support from the network) was revised adding a new higher accuracy clock (“clock class C").
Corrigendum 1 to G.8273 (Framework of phase and time clocks) was also consented at this meeting.
Several new work items have been agreed. Most of them related to progress with the existing recommendations. A new recommendation, G.mtn-sync, will address aspects such as the MTN synchronization architecture and synchronization related requirements (e.g., synchronization messaging encapsulation, timestamp generation, applicable PTP profiles).
Q13/15 plans to progress its activities with 3 Interregnum e-meetings (in December 2020, February or March 2021 and April 2021).
Q14/15 made good progress at this meeting. It consented three new Recommendations G.8052.1 (Ethernet OAM IM/DM), G.8152.1 (MPLS-TP OAM IM/DM), G.8152.2 (MPLS-TP Resilience IM/DM) and five revised Recommendation G.7710 (Common equipment management requirements), G.874 (ONT NE management requirements), G.8051 (Ethernet NE management requirements) & G.8151 (MPLS-TP NE management requirements), & G.7718 (Framework for the management of MCC components and functions).
Progress was made on the other active work items, including MC component/function management information model (G.7719), Optical media management (G.876), and MTN management (G.8350).
Q14/15 also initiated nine new work items, including new G.Suppl.media-im-ex, revision to G.875 (OTN NE IM) and amendments to G.874, G.7710, G.7712 (DCN), G.7718, G.8052.1, G.8152.1, & G.8152.2.
Q14/15 plans to hold four tracks of correspondence activities (each of which includes a series of 6 to 7 virtual meetings) on modeling coordination (with invited modelling experts from IEEE 802.1, IEEE 802.3, ONF, MEF, BBF, IETF, TM Forum), MC management & operation, MTN management & ECC, and OTN & Optical media management.
Decisions (ITU-T SG15, September 2020)
Consent
WP1/15 – Consent:
| Recommendations | N=new
R=rev. | Title | Text in
Doc(s) |
| G.984.5 Amd2 | N | Gigabit-capable passive optical networks (GPON): Enhancement band - Amendment 2 | TD589R1/P |
| G.9806 Amd1 | N | Higher speed bidirectional, single fibre, point-to-point optical access system (HS-PtP) - Amendment 1 | TD601R2/P
A5 in TD631/P |
| G.9807.1 Amd2 | N | 10-Gigabit-capable symmetric passive optical network (XGS-PON) - Amendment 2 | TD626R1/P |
| G.987.2 Amd2 | N | 10-Gigabit-capable passive optical networks (XG-PON): Physical media dependent (PMD) layer specification - Amendment 2 | TD628/P |
| G.989.2 Amd1 | N | 40-Gigabit-capable passive optical networks 2 (NG PON2): Physical media dependent (PMD) layer specification - Amendment 1 | TD627/P |
| G.994.1 Amd2 | N | Handshake for DSL transceivers (2018 - Amendment 2) | TD610R2/P |
| G.997.2 Amd2 | N | Physical layer management for G.fast transceivers (2019 – Amendment 2) | TD612R1/P |
| G.997.3 | N | Physical layer management for MGfast transceivers | TD611R2/P |
| G.9701 Amd3 | N | Fast access to subscriber terminals (G.fast) - Physical layer specification (2019 - Amendment 3) | TD617R1/P |
| G.9711 | N | Multi-gigabit fast access to subscriber terminals (MGfast) – Physical layer specification | TD619R1/P
A.5 in TD646/P |
| G.9960 Cor2 | N | Unified high-speed wireline-based home networking transceivers – System architecture and physical layer specification – Corrigendum 2 | TD616R1/P |
| G.9961 Amd3 | N | Unified high-speed wireline-based home networking transceivers – Data link layer specification – Amendment 3 | TD618R1/P |
| G.9991 Cor1 | N | High-speed indoor visible light communication transceiver – System architecture, physical layer and data link layer specification – Corrigendum 1 | TD594R1/P |
| G.9991 Amd2 | N | High-speed indoor visible light communication transceiver – System architecture, physical layer and data link layer specification – Amendment 2 | TD593R1/P
A.5 in TD637/P |
| G.9963 Amd1 | N | Unified high-speed wireline-based home networking transceivers – Multiple input/multiple output specification – Amendment 1 | TD625R1/P
|
WP2/15 – Consent:
| Recommendations | N=new
R=rev. | Title | Text in
Doc(s) |
| G.650.1 | R | Definitions and test methods for linear, deterministic attributes of single-mode fibre and cable | TD613R1/P |
| G.672 | R | Characteristics of multi-degree reconfigurable optical add/drop multiplexers | TD587R1/P |
| G.694.1 | R | Spectral grids for WDM applications: DWDM frequency grid | TD623/P |
| G.971 | R | General features of optical fibre submarine cable systems | TD614R1/P |
| G.972 | R | Definition of terms relevant to optical fibre submarine cable systems | TD609R2/P |
| G.977.1 | N | Transverse compatible DWDM applications for repeatered optical fibre submarine cable systems | TD606R2/P |
| L.111 (ex L.oha) | N | Optical fibre cables for in-home applications | TD590R2/P |
| L.151 | R | Installation of Optical Ground Wire (OPGW) Cable | TD615R3/P |
| L.330 (ex L.tifm) | N | Telecommunication infrastructure facility management | TD585R1/P
|
WP3/15 – Consent:
| Recommendation | N=new
R=rev. | Title | Text in
Doc(s) |
| G.8011 | R | Ethernet service characteristics | TD629R1/P
A.5 in
TD641/P |
| G.8112/Y.1371 | R | Interfaces for the MPLS transport profile layer network
(Supersedes G.8101) | TD592R1/P
A.5 in
TD643R1/P |
| G.709/Y.1331 Amd.1 | N | Interfaces for the optical transport network (OTN) | TD574R1/P |
| G.709.1/Y.1331.1 Amd.2 | N | Flexible OTN short-reach interfaces - Amendment 2 | TD588R1/P |
| G.709.3/Y.1331.3 | R | Flexible OTN long-reach interface | TD580/P |
| G.798 Amd.3 | N | Characteristics of optical transport network hierarchy equipment functional blocks - Amendment 3 | TD597R1/P
A.5 in
TD598/P |
| G.8312 (ex G.mtn) | N | Interfaces for the metro transport network | TD568R1/P
A.5 in
TD600R1/P |
| G.807 Amd.1 | N | Generic functional architecture of the optical media network - Amendment 1 | TD570R1/P |
| G.872 Amd.1 | N | Architecture of the Optical Transport network (OTN) - Amendment 1 | TD571R1/P |
| G.7701 Amd.2 | N | Common control aspects - Amendment 2 | TD572R1/P |
| G.8110.1 Amd.1 | N | Architecture of the Multi-Protocol Label Switching transport profile layer network - Amendment 1
(Supersedes G.8101) | TD591R1/P
A.5 in
TD638/P |
| G.8310 (ex G.mtn-arch) | N | Functional architecture of the metro transport network | TD569R1/P
A.5 in
TD632/P |
| G.8261/Y.1361 Amd.2 | N | Timing and synchronization aspects in packet networks - Amendment 2 | TD595R1/P |
| G.8271.1/Y.1366.1 Amd.1 | N | Network limits for time synchronization in Packet networks with full timing support from the network - Amendment 1 | TD596R1/P |
G.8273/Y.1368
Cor 1 | N | Framework of phase and time clocks Cor 1 | TD630/P |
| G.8273.2/Y.1368.2 | R | Timing characteristics of telecom boundary clocks and telecom time slave clocks for use with full timing support from the network | TD607R1/P |
| G.8273.3/Y.1368.3 Rev | R | Timing characteristics of telecom transparent clocks for use with full timing support from the network | TD608R1/P |
| G.8275/Y.1369 | R | Architecture and requirements for packet-based time and phase delivery | TD603R1/P |
| G.8275.1/Y.1369.1 Amd.1 | N | Precision time protocol telecom profile for phase/time synchronization with full timing support from the network - Amendment 1 | TD604R1/P* |
| G.8275.2/Y.1369.2 Amd.1 | N | Precision time protocol telecom profile for phase/time synchronization with partial timing support from the network - Amendment 1 | TD605R1/P* |
| G.874 | R | Management aspects of optical transport network elements | TD576R1/P |
| G.7710/Y.1701 | R | Common equipment management function requirements | TD575R1/P |
| G.7718 | R | Framework for the management of MC components and functions | TD579R1/P |
| G.8051/Y.1345 | R | Management aspects of the Ethernet Transport (ET) capable network element | TD577R1/P
A.5 in
TD639/P |
| G.8052.1/Y.1346.1 | N | Transport OAM Management Information/Data Models for Ethernet Transport Network Element" | TD581R1/P*
A.5 in
TD647/P |
| G.8151/Y.1374 | R | Management aspects of the MPLS-TP network element | TD578R1/P |
| G.8152.1/Y.1375.1 | N | MPLS-TP NE OAM Information Model & Data Model | TD582R1/P*
A.5 in
TD640/P |
| G.8152.2/Y.1375.2 | N | MPLS-TP NE Resilience Information Model & Data Model | TD583R1/P*
A.5 in
TD648/P
|
* 30-day editing period was requested before initiating last call.
Agreement
WP1/15 - Agreement:
Doc. #/
Ref. | N=new
R=rev. | Title | Text in Doc(s) |
| G Suppl 66 | R | 5G wireless fronthaul requirements in a passive optical network context | TD602R2/P |
| G Suppl 49 | R | Rogue optical network unit (ONU) considerations: Revision 2 | TD622R2/P |
| | N | Technical paper on the use of G.hn technology for smart grid | TD624R1/P
|
WP2/15 - Agreement:
Doc. #/
Ref. | N=new
R=rev. | Title | Text in Doc(s) |
| L Suppl.crg | N | Optical fibre cable Recommendations and standardization guideline | TD584R2/P
|
WP3/15 - Agreement:
Doc. #/
Ref. | N=new
R=rev. | Title | Text in Doc(s) |
| G.709.2/Y.1331.2 Appendix II Cor 1 | N | OTU4 long-reach interface | TD634/P |
| G.Sup.58 | R | Optical transport network module framer interfaces | TD586R1/P |
| G.Sup.mtn-migration | N | Migration of a pre-standard network to a metro transport network | TD567R3/P |
| G.Sup.sub1G | N | Sub 1 Gbit/s services transport over OTN | TD573R3/P |
| G.8001 | R | Implementers' guide for Recommendation ITU-T G.8001/Y.1354 | TD642/P |
| G.8101 | R | Implementers' guide for Recommendation ITU-T G.8101/Y.1355 | TD645/P
|
