Executive Summary, SG15, July 2026

​​​​Montreal, 29 June - 10 July 2026
ITU-T Study Group 15
Networks, Technologies and Infrastructures for Transport, Access and Home
Study Group 15 Chair: Glenn Parsons

Study Group 15 held its third meeting of the 2025-2028 study period in-person in Montreal, Canada from 29 June – 10 July 2026, had more than 500 registrations and was attended by 377 delegates representing 40 countries.

The meeting received 438 contributions and 458 TDs.  The meeting observed the 12-day contribution deadline of Recommendation ITU-T A.1, and almost all of the contributions to this meeting were submitted using Direct Document Posting (DDP).
SG15 approved one Amendment of a Recommendation, consented 33 texts (2 new and 12 revised Recommendations, 16 Amendments, and 3 Corrigenda), and agreed 6 supplements and 3 technical reports.
Interim activities prior to the next SG15 plenary have been planned as virtual or in-person, consisting of 24 single-day or multiple-day meetings.

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.

SG15 generated 43 Liaison Statements.  These included liaisons to IEEE 802.1 and 802.3 on incorporation by reference and to IEC TC86 SC86A on hollow core fibre new work.

The SG15 Regional Group for Africa reported on its first meeting and its leadership team was confirmed.
Three workshops focused on the impact of AI were co-located with the plenary meeting, including a joint workshop with IEEE 802.

WP1/15 – Transport aspects of access, home and smart grid networks

WP1/15 Chair: Ian Horsley, Vice Chair: Frank Van der Putten
WP1/15 approved 1 Recommendation, consented 4 Recommendations, agreed 2 Supplements, agreed 1 Technical report and initiated 7 new work items.

Q2/15 met for 5 days reviewing 70 contributions and around 25 temporary documents. All the consent and agreement documents were progressed to decision. Joint meetings were held with Q6, Q11 and Q12 (regarding WBBA cooperation) and with Q5 and Q6 (regarding hollow core fibre). Several face-to-face and teleconference interim meetings were planned, and outgoing liaisons were prepared.
The work program was updated, and new work was started on Multi-PON cooperation based on combo ONU and a revision to "Passive optical network protection considerations", as well as several revision and amendment projects.
Significant work continued on Very High Speed PON (VHSP) and AI for networks and networks for AI.  The meeting consented one Recommendation and agreed one Supplement, updating the OMCI (ONU M&C Interface) to capture new service features and clarifications, and documenting use cases and requirements for Low Layer Split Mobile Fronthaul over T(W)DM PON.

Q3/15 met for 4 days and reviewing 41 contributions, 8 incoming liaison statements and preparing 7 outgoing liaisons.
The work program was updated, and new work was started on AI-enhanced business networking, the User Services Platform, using FIP technologies for In-Vehicle Optical Networking, coexistence of G.fin and G.Xfin fibre in premises network systems and the 10G system architecture for high speed fibre-based in-premises networking, as well as several revision and amendment projects. 
The work progressed on the various families of Recommendations under the group responsibilities (G.hn, G.fin/G.Xfin, G.p2pf, G.dop, etc …).
One draft Recommendation adding new functions to the WLAN management control interface for FIP was forwarded for approval after finishing the last call comments. Three draft Recommendations were forwarded for consent on the 10G data link layer for high speed fibre-based in-premises networking, and amendment and corrigenda to Narrowband OFDM power line communication and radio frequency transceivers.
2 Supplements on “Enhanced on-premises networking with computing functions" and “Network characteristics and use cases for the 10Gbps broadband era" were forwarded for agreement.​​

Q4/15 met for half a day in Montreal. One contribution was received and reviewed. The work programme was reviewed and confirmed. Contributions are invited for the next meeting to progress the work.
A joint session including Q2, Q3, was held regarding contributions and the draft for the supplement on “Network characteristics and use cases for the 10Gbps broadband era" and discussions on the E2E architecture of access and home networks.​ 

WP2/15 – Optical technologies and physical infrastructures

WP2 Chair: Sudipta Bhaumik; WP2 Vice-Chair: Fabio Cavaliere
All the four Questions of WP2 met during the plenary.
Questions of WP2/15 obtained consent for 4 Recommendations and 1 corrigendum, agreed 2 supplements and 1 technical report and initiated 16 new work items. Additionally, WP2 prepared 6 outgoing liaisons and three flyers. 

Q5/15 finalized the Revisions of Recommendations L.108 (Optical fibre cable elements for microduct blowing-installation application), corrigenda of L.105 (Optical fibre cables for drop application), revision of L.Suppl.39 (Optical fibre cable Recommendations and standardization guideline) and a new L.Suppl.65 (ex., L.suppl.ne) containing comprehensive guidelines for national experiences on L-series optical fibre cable and installation. A new work item to develop a technical report "Hollow-core fibre technologies and systems," was approved as a joint project among Q2, Q5, and Q6/15. The scope of the revision work of G.650.1 was enhanced to include geometrical parameters of weakly coupled multi-core fibre (WC-MCF).
One interim meeting in Geneva during 5-6 Nov 2026 is scheduled to make progress on WC-MCF related Recommendations. Correspondence activities are planned to advance revision work on multiple Recommendations, on new Recommendations on weakly coupled multicore fibres and its test methods, and the technical report on hollow core fibres.

Q6/15 consented to two revised Recommendations: G.697 (Optical monitoring for dense wavelength division multiplexing systems) and G.672 (Characteristics of multi-degree reconfigurable optical add/drop multiplexers). A new technical report TR.fsc on feedforward sensing was agreed upon during this meeting. The meeting made progress on TR.ION-aiDC under the framework of ION-2030 and on 800G DWDM application in revised G.698.2. Several Recommendations are open for revision work such as B1T (Beyond one Tera) DWDM applications to be included in revised G.698.2 and G.696.1,  25G applications in revised G.641(ex.G.fso), and co-propagation configuration in revised G.681(ex.G.dfos). Another new work item to develop a technical report TR.opg on "optical transmission requirements and technologies in power grids" was approved.
An interim RGM hosted by China Unicom, will be held in Chengdu (China) from 10th to 13th Nov 2026.

 Q7/15 consented to the revision of L.361 (ID tag requirements for network infrastructures management) and agreed to start three new work items, such as revision works for L.203 (Electric power supply for equipment installed as outside plant), L.400 (Optical fibre splices) and L.403 (Optical branching components (non-wavelength selective)).
Revision of L.400 is the first MCF-related topic addressed in Q7/15. Draft new Rec. L.nis (network infrastructure sharing) was discussed and refined.

 Q8/15 made progress on new Recommendation G.9730 “General features of optical fibre submarine cable systems with sensing capabilities" and started a new study item G.scjb “Characteristics of optical fibre submarine cable jointing box"

​WP3/15 – Transport network characteristics

WP3 Chair: Tom Huber; WP3 Vice-Chair: Silvana Rodrigues
WP3 consented 24 Recommendations or amendments, agreed two supplements and a technical report, started 40 new work items, and sent 12 liaisons.

WP3 chair summary

Q10/15 has initiated the approval process on revised Recommendations G.8011 “Ethernet services characteristics" and G.8020.3 “Ethernet", and on G.8032 “Ethernet ring protection switching" Corrigendum 2. It also initiated work on new G.8020.x “Bridges and bridged networks".
Q11 has continued to refine and enhance the suite of OTN and MTN Recommendations and continues its focus on the definition of beyond 1 Tbit/s OTN. (B1T).

Q12/15 continued work on media architecture Recommendations to expand the architecture of the information/media boundary resulting in the initiation of a new Recommendation G.800.1 “Functional architecture of digital and analogue information layer". A technical report on Enhanced network operations (ENOs) was completed and new Recommendation initiated on the architecture ENOs.
Q12/15 updated the OTNT Standardization Work Plan.

Q13/15 continued its work to enhance the accuracy and robustness of time and frequency distribution. Q13/15 also is continuing work on extending the ITU defined synchronization frameworks and profiles to apply to synchronization in data centres. In this context, work is progressing on the definition of a profile suitable for use in data centre applications (G.FTS-Lite) and a new work item has been agreed at this meeting for defining a clock to support this profile (G.FTS-Lite-clk)

Q14/15 is continuing to extend the suite of management Recommendations to allow management of the new functions recently defined by Q11 and Q13, including new work items to enhance OTN management requirements, OTN ECC and protocol for automatic discovery etc. The technical report on optical physical infrastructure resources management for transport networks has been progressed and the coordination with Q7 is scheduled.

Q14/15 is continuing to work in cooperation with IEEE 802.1, IEEE 1588, IEEE 802.3, Linux Foundation ONMI, MEF, BBF, and IETF to provide consistent information models and YANG data models for transport networks; the current focus of this work is on the management of network synchronization and Ethernet.

Q14/15 is continuing to enhance the draft guidelines for ITU-T Q14/15 draft Recommendations with UML and YANG models. 

Per Question highlights:

Q10/15 consented three documents: revised G.8011 “Ethernet services characteristics" (additionally addressing carrier Ethernet-centric MEF 23.2.2, 47.1, 140, and 151 standards), revised G.8020.3 “Ethernet" edition 3.0 (adding IEEE Stds 802.3da and 802.3dk to IEEE Std 802.3-2022 and its amendments incorporated by reference in this Recommendation), and G.8032 “Ethernet ring protection switching" Corrigendum 2 (regarding transfer time, interconnection flush logic, and terminology). Q10/15 proposed new work items agreed at this meeting toward consent in February 2027 of a new G.8020.x “Bridges and bridged networks" (to incorporate IEEE Std 802.1Q and its published amendments by reference) and of a revision of G.8020.3 edition 3.0 (to continue aligning with the evolution of IEEE Std 802.3). Three liaison responses to IEEE 802.1, IEEE 802.3, and Mplify Alliance were agreed related to G.8020.x, G.8020.3, and G.8011, respectively. Q10/15 may hold an interim E-meeting if AAP comments are received on the documents consented at this meeting.

Q11/15 made significant progress on all of its agenda topics, with six consented Recommendations, one agreed information document and approval of 13 new formal work items.  Q11 continued its focus on work associated with OTN for rates beyond 1 Tbit/s (B1T).  Other work topics included items related to fine grain MTN (fgMTN), and fine grain OTN (fgOTN). 

The key meeting output was the revision of the Flexible OTN (FlexO) Recommendations G.709.1 (common elements) and G.709.6 (B400G long reach interfaces) to include the core B1T interface specifications.  These specifications include expanding the networking capabilities of FlexO with the introduction of new Path and Section layer signals.  Further, G.709.6 now specifies a 1.6 Tbit/s long reach interface using the same optical interface as OIF 1600ZR+, allowing common use of optical modules between G.709.6 B1T and 1600ZR+.  Note that the 1600ZR+ uses FlexO as the basis for its frame format.  New work items were approved for each to develop further enhancements.  In addition, new Recommendation G.709.7 (FlexO module-to-framer interfaces) was approved, moving material that has previously been documented in G.Suppl.58 and newer FlexO electrical interfaces into a common normative Recommendation. 

MTN Recommendation G.8312 was updated to include new fgMTN client signal mappings, with a new work item approved for a corresponding update to G.8321 (MTN equipment functional blocks). 

Protection switching discussions resulted in new work items for B1T linear network protection in G.873.1 and documenting a fgOTN protection mechanism optimized for power grid communication applications in new informative supplement G.sup.fgotnlp.

Other new work items included updates to the OTN equipment functional block Recommendations G.798, G.798.2, G.798.3 and G.798.4, updates to Recommendation G.709.20 (Overview of fine grain OTN), and new Supplement G.sup.FlexOPy-o-ne "Transport of FlexO path on Ethernet optimized FlexO". 

Q11/15 plans to hold a face-to-face interim meeting in 19 – 23 October 2026 in Nanjing, China. 

Q12/15 completed a technical report with Q14 on “Enhanced network operations for transport networks" in GSTR.ENO. This is the first output from the study of AI/ML/DT applications that has received contributions over multiple plenaries. It integrates these applications with non-AI based applications used in conjunction with management and control systems. From this work a new G.eno-arch “Architecture of enhanced network operations for transport networks" was initiated.

Following from the publication of GSTR.ION-2030, interest continues in this framework and a new technical report “Transport network support of IMT-2030/6G" was initiated to study wireless aspects.

Amendments to G.807 and G.7702 were completed and progress was made in G.872 to align with recent Q11/15 work on B1T and the module-to-framer interface.

In media architecture, an Amendment to G.807 was completed. Study continued on the architecture of the information to media boundary and considerable progress was made in the understanding of the analogue information layer. As a result, a new Recommendation G.800.1 “Functional architecture of digital and analogue information" and a Revision to G.807 were initiated. These will enable important SG15 topics to be modelled, in particular distributed fibre sensing of vibrations.

Q13/15 continued the work on requirements and solutions for time and frequency synchronization. Several Recommendations have been consented and one Supplement was agreed at this meeting. Enhancements to PTP profiles have been addressed in the amended G.8275, G.8275.1, G.8275.2. G.8262.1, the enhanced synchronous equipment clock, has been revised adding jitter requirements for 10 Gb/s and 25 Gb/s interfaces. The Primary reference time clocks (G.8272, G.8272.1, G.8272.2) have all been updated with amendments, adding further details on the use of GNSS. G.8260 has been revised with addition of new definitions related to time synchronization. G.811.1 (enhanced PRC) and G.812 (node clock) have been enhanced with synchronous Ethernet interfaces.

Further progress has been made on the topic of synchronization in data center with a new revision of the Supplement G.Sup92. A liaison has been exchanged with IEEE and OCP concerning synchronization in data centres.

Work has also been done on other recommendations planned to be consented at future SG15 plenaries. The time sync clock (G.8273.2) was updated, among other things, with clarifications on the use of a Local Time Reference. Solutions to increase resiliency of the synchronization networks have been discussed as part of G.8274. Work has been done on G.781 (synchronization layer functions for synchronization over the physical layer), e.g., addressing aspects related to the extended SSM, and G.781.1 (Synchronization layer functions for packet-based synchronization) concerning PTP message delays. The work on enhanced Partial timing support (ePTS) has continued to make the Supplement ready for agreement at a future SG15 plenary. Progress has been made on the Supplement addressing monitoring aspects of the PRTC (G.Suppl-PRTC-M). Progress has also been made on the PTP profile based on full timing support without the use of synchronous Ethernet (G.FTS-Lite). On this respect, a new work item (G.FTS-Lite-clk) has been agreed to define the clock for this profile.

Several new work items have been approved to continue the work on the Recommendations consented at this meeting. Discussions have started on the synchronization needs for 6G.

Q13/15 plans to hold an in-person interim meeting in December 2026 and a series of virtual meetings on the synchronization in data centres. 

Q14/15 continued the work on common transport management requirements and technology-specific (including OTN, MTN, Ethernet, MPLS-TP, Synchronization and Media) information models and YANG models. Two amendments were consented, including G.7713 Amd.1 addresses the call and connection management in hybrid control architecture and G.7721 Amd.2 mainly addresses the monitoring requirements of the time/phase offset between local time reference and PTP.
Four new work items were created to revise G.874 OTN management requirements to align with Q11 restructured G.798-series Recommendations and G.7710, amend G.7712 DCN architecture to support using FlexO management communication channels to constitute OTN ECC, amend G.7714.1 Protocol for automatic discovery to extend the applicability to FlexO section, OTUCn and ODUCn layers and amend G.7721.1 Data model of synchronization management to enhance the YANG model.

The draft guideline for ITU-T Q14/15 draft Recommendations with UML and YANG models, was reviewed and updated. A joint e-Meeting with IIOSMI modelling experts was held to coordinate the UML and YANG models.

​Q14/15 plans to hold one in person interim meeting with Q12 in October 2026, three tracks of correspondence activities, including e-Meetings, to progress the work items. Another joint correspondence activity including an e-Meeting with Q7 was planned for the coordination on GSTR.OPIM.

One spontaneous liaison for the coordination on IM/DM with IEEE 802.1, IEEE PNCS (P1588), IEEE 802.3, MEF, IETF, BBF, TM Forum, Linux Foundation ONMI, O-RAN Alliance WG9 was agreed.

Decisions (ITU-T SG15, July 2026)
Approval

WP1/15 - AAP Approval

Consent

WP1/15 - Consent

​WP2/15 - Consent

WP3/15 - Consent

​WP1/15 - Agreement

WP2/15 - Agreement

WP3/15 - Agreement

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