The 21st European Telecommunications Standards Institute (ETSI) Zero-touch Network and Service Management (ZSM) meeting, held from November 22 to 24 in Sophia Antipolis France, completed a PoC demonstration on the automation of Intent-based cloud leased line services. The PoC participants include China Mobile, China Unicom, Huawei, AsiaInfo, and Xidian University. The PoC is a collaborative effort involving standard bodies, open source communities, and industrial partners whose goal is to accelerate the advancement of autonomous networks (AN) and also to explore its applications.

Cloud services are constantly reshaping social production and lifestyles. Home broadband applications (such as cloud games), large enterprises (such as governmental and finance enterprises), and small- and medium-sized enterprises (such as hospitals and e-commerce enterprises) are greatly facilitated by cloud services. Enterprises are using cloud services to reduce O&M costs, and applications are gradually being migrated to the cloud. The multi-cloud strategy and multi-cloud services have become a trend in the industry. One-hop cloud access via OTN has been widely used in the industry and has become the mainstream choice for streamlining enterprises and cloud leased line services due to its various advantages, including high bandwidth, low latency, hard isolation, high reliability, and one-hop cloud access. However, it has always been difficult to manage services on optical transport networks due to network configuration complexity and multi-vendor interoperability and collaboration challenges. The PoC proposes a solution to these changelings. To cope complexity, the architectural design, which is based on ZSM 002, 008, 009-1 and 011, is a turnkey solution which provides fully automated and Intent-based service fulfillment and assurance of cloud leased lines. Secondly, the solution uses IETF ACTN MPI standard interfaces to solve the challenges of multi-vendor and multi-domain interoperability in the transport management domain. The solution implementation is open source and is released in LFN ONAP Kohn release.

For the PoC demonstration setup, six Huawei POTN devices and two Huawei optical network controllers (iMaster NCE-T) are used to construct a two-domain network testbed for the cloud leased line test cases. ONAP serves as the user intent lifecycle manager and also the E2E network orchestrator.

Figure 1: Figure 1: PoC Demo Setup

ONAP’s Intent manager module resumes the Intent Owner’s role, as defined in ZSM 011. It receives and translates user intents into intent data models and sends them to the service orchestrator, which is the Intent Handler. It converts the intent data models into interfaces that comply with the IETF ACTN standards, invokes the ACTN interfaces of the vendor's domain controller to implement E2E automatic provisioning of cloud access services, and implements closed-loop management of user intents for on-demand and flexible bandwidth adjustment based on the telemetry data provided by the domain controllers. The PoC performed the following testcases: user intent creation, deletion, and modification, automated cloud leased line service provisioning through intent interface, and on-demand flexible service bandwidth adjustment based on service performance data. For the leased line service creation, both symmetric VLAN and asymmetric VLAN scenarios have been tested.

In addition to the collective efforts and common goals, the PoC participants and ETSI ZSM also shared their individual perspectives and expectations regarding the PoC. Firstly, from China Mobile’s perspective, it has put forward the practical goal of "achieving L4 AN by 2025" and has formed mature AN capability improvement methods to guide the large-scale, systematic, and continuous AN practice throughout the network based on all-round theoretical innovation and exploratory practices. China Mobile will implement standard R&D practices (align with organizations such as ETSI/3GPP/TMF/CCSA) and explore open-source projects (align with consortiums such as LFN), accelerate technological innovation of Intent-Driven Network (IDN) management, and actively share best practices with the industry to build consensus.

China Unicom is pleased that the PoC verifies the feasibility of combining the ETSI ZSM E2E network automation architecture with IETF ACTN standards. It is the first carrier in China to use ACTN interfaces for commercial use on SDOTN networks, and has formed a two-level service orchestration architecture and implemented commercial application deployment. Wang Guangquan, chief engineer of China Unicom Research Institute, said, "The development and application of network intelligence technologies are hot topics. We are happy to see ACTN interfaces play an important role in the architecture of network intelligence technologies. We will continue to explore the collaborative application of ACTN interfaces across technical fields and will contribute use case scenario designs related to intent interfaces for ETSI ZSM to continuously promote the development of network intelligence technologies."

Dr. Christopher Janz, director of Canada Research Center of Huawei Optical Business Product Line, said, "The PoC organized by ETSI ZSM has made further explorations in actual application. This proves that our cooperation with enterprises such as Chinese carriers in ONAP on open-source platforms and AN is quite effective. It also demonstrates the maturity of ACTN interfaces in automatic service provisioning and service O&M scenarios, and the great potential of ACTN interfaces to play a greater role in AN in the future."

AsiaInfo Technologies believes that the AN architecture will provide zero-wait, zero-touch, and zero-fault user experience for vertical industries and consumers with the help of fully automated network and ICT intelligent infrastructure, agile operation, and all-scenario services. This is the trend of carriers' future network development and also an important feature that the next-generation OSS must support. The PoC has verified the feasibility of IDN for the cloud leased line scenario. AsiaInfo will continue to develop network intelligence technologies and products that are compatible with multi-vendor network devices to support the continuous evolution and rapid implementation of AN.

Professor Yang Chungang at Xidian University believes that this test further verifies the feasibility of the intent-driven autonomous optical network. The interface specifications will help accurately and efficiently express the intent of external cloud services to the network control end. Professor Yang's team has completed the research, demonstration, and practice of key intent closure technologies such as intelligent intent translation, intent closure verification, and autonomous policy generation of the IDN, and built a demonstration system for on-demand orchestration and management of 6G mobile communications systems and intelligent routing of programmable networks. They believe that the intent-driven AN urgently requires key technology research on endogenous intent flow, such as identification, representation, and translation of endogenous intents. His team will collaborate with the industry to tackle problems and implement more intent-driven AN application cases and standards.

In conclusion, Dr. Diego Lopez, ETSI ZSM chair, said, “This PoC is a practical demonstration of how the ZSM framework can be applied to integrate different technologies and solutions to achieve a practical realization of the ideas around intent-based networking. Applied to a rather realistic, non-trivial scenario, it shows a path for network service evolution towards autonomous networks, and corroborates the advantages of the collaboration between standards bodies and open-source communities”.

The article is co-developed by ETSI ZSM ISG, China Mobile, China Unicom and Huawei Technologies.

This content is sponsored by Huawei Technologies.