Industry Specification Group (ISG) Zero Touch Network and Service Management (ZSM) Activity Report 2021

Chair: Diego Lopez, Telefonica

Examining use cases and requirements for zero-touch network and service management; producing specifications to define a future-proof, end-to-end operable framework, solutions and core technologies for autonomous networks.

The pivotal deployment of 5G and network slicing has triggered the need for a radical change in the way networks and services are managed and orchestrated. In particular there is a need to accommodate:

  • an increase in the overall complexity resulting from the transformation of networks into programmable, software-driven, service-based and holistically managed architectures, and
  • the unprecedented operational agility required to support new business opportunities enabled by technology breakthroughs, such as network slicing.

These new network deployments come with an extreme range of requirements, including massive seemingly infinite capacity, imperceptible latency, ultra-high reliability, personalized services with dramatic improvements in customer-experience, global web-scale reach, and support for massive machine-to-machine communication.

Maximizing the efficiency of end-to-end network operations requires increased automation of functions that are currently administered with direct human intervention, such as configuration and capacity management. In particular, the automation of network and service management has become an urgent necessity to deliver 5G services with speed and agility while ensuring their economic sustainability.

Driven by documented business scenarios, ISG ZSM is examining requirements for tomorrow’s zero-touch networks.  The group’s ultimate target is to enable network autonomous operation steered by high-level policies. These autonomous networks will be able to self-manage and self-organize (configuration, healing, assurance, optimization, etc.) without human intervention beyond the initial transmission of intents.

ISG ZSM works to strengthen the collaboration with key organizations to promote the adoption of and alignment with the ZSM architecture and solutions, ensuring that automated end-to-end network and service management can be achieved.

In 2021 ISG ZSM published two new Group Specifications, together with a new Group Report.

Group Specification GS ZSM 003 (published June 2021) defines an architecture blueprint and solutions for zero-touch management and orchestration of end-to-end, cross-domain network slicing, supporting both fulfilment and assurance processes. Network slicing spans different technological domains, from the User Equipment (UE) through, for example, the access network, transport network, core network, to the application. The new specification leverages existing industry specifications, stitches them together and provides a federated solution. The alignment and leverage of synergies across ETSI ZSM, 3GPP, O-RAN, IETF, BBF, TMF, GSMA NEST, etc. is essential to enable the delivery of end-to-end network slicing that can satisfy the requirements from vertical industries and the demands of network operators.

GS ZSM 009-1 (also published June 2021) represents the first part of a multi-part Group Specification on ‘closed loop’ automation that can be empowered by advanced machine learning and artificial intelligence. It specifies ‘governance’ services that allow the creation, execution and life-cycle management of a closed-loop, as well as the steering of its behaviour. A closed-loop enables the continuous optimization and adaption of network and resource utilization as well as automated service assurance and fulfilment. The specification provides capabilities to support coordination, delegation and escalation between closed loops to ensure intelligent, consistent and coherent operation. Alignment and leverage of this document horizontally and vertically by 3GPP and O-RAN is essential to ensure cross-use cases, cross-domains, cross-planes, interoperable, unified and consistent closed-loops and cognitive operation.

The threat surface in the ZSM environment is extensive due to the openness of the ZSM framework and the nature of related emerging technologies such as AI/ML, data lake and cloud-native applications. Group Report GR ZSM 010 (published July 2021) identifies potential security threats related to the ZSM framework and solutions and proposes mitigation options that should be considered by the ZSM specifications to ensure that the automated processes are secured and deliver the intended business outcomes. The report introduces countermeasures and potential requirements to address the threats and risks.

During the year progress was meanwhile made on several further Work Items:

GS ZSM 008 ‘Cross-domain E2E service lifecycle management’ - this normative document aims to define management processes during the lifecycle of E2E services, and the interactions between E2E service management domain and management domains.

Based on the generic enablers and architectural elements for closed loops as defined in the previously-published ZSM 002 and ZSM 009-1, the ongoing Group Specification GS ZSM 009-2 is the second part of our specification presenting solutions for automation of E2E service and network management use cases. It is accompanied by GR ZSM 009-3a study investigating advanced topics related to closed-loop operations such as learning and cognitive capabilities, ways to set and evaluate levels of oversight, autonomy, and operational confidence in the behaviour of closed loops.

Intent-based management enables simpler and more user-friendly expressions of input information and higher flexibility in automation. GR ZSM 011 will present a study of intent-driven autonomous networks, investigating the potential use of intents as key enabler for enhancing autonomous network and service management within a ZSM framework.

GR ZSM 012 will specify extensions and new capabilities – the so-called AI enablers – for the ZSM framework reference architecture. The set of AI-enabling capabilities is specified as management services, complementing the existing management services defined in GS ZSM 002. The study focuses on AI-related areas such as data handling and analytics, action, interoperation, governance and execution environment.

GR ZSM 013 is a Group Report on the automation of CI/CD (continuous integration / continuous development) for ZSM services and managed services. lt studies use cases, potential requirements and possible solutions of automating CI/CD of software-related primarily to management services and/or functions and secondarily to managed services.

Building on work in GR ZSM 010, the new draft on security aspects (GS ZSM 014) specifies security capabilities for the ZSM framework architecture. The set of security capabilities focuses on automatic security governance of management services, with a focus on automatic security governance of management service/function including AI/ML-enabled service/function, adaptive trust relationship between management domains, dynamic access control and exposure of ZSM service, as well as supporting intelligent security services built on capabilities of ZSM framework. It also documents deployment aspects of the security scenarios to validate the applicability of the security requirements and management services/functions.

Meanwhile, our landscape document GR ZSM 004 which compiles information on activities in other SDOs, fora and open source communities was revised including recent and future developments.

A new edition of the group’s existing PoC (Proof of Concept) framework GS ZSM 006 meanwhile nears completion.

See the full list of current ISG ZSM Work Items here.

During the year ISG ZSM continued its regular exchange of information with other ETSI bodies (notably ISG NFV, ISG ENI) as well as with key external organizations (ITU FG AN, O-RAN, 3GPP, LFN ONAP), hence maintaining fruitful collaborations to promote the adoption of and alignment with the ZSM architecture and solutions. The ISG intends to maintain the overall mindshare and architectural integrity in ZSM (beyond ETSI) and strengthen these collaborations to ensure the leverage of synergies and alignment.

The group has continued its steady growth, gaining three new signatories in 2021. It has now attained 77 signatories of its ISG agreement, of which 50 are ETSI Members. Members/Participants include 22 operators, as well as leading vendors and technology providers.