Page 526 - Cloud computing: From paradigm to operation

2 Cloud Computing management

8 Metadata framework for NaaS service lifecycle management

This clause aims to specify the metadata framework in NaaS service lifecycle management by reflecting the
interoperability and integration of the NaaS service metadata, especially in the environments of DevOps and
CI/CD.

As described in [ITU-T Y.3522], metadata is used in the entire cloud service lifecycle management, from
design, deployment, operation, to retirement stages. For NaaS service, closed-loop automation management
is achieved by using data models of NaaS service, NaaS service operational policy, and NaaS resource, as a
linkage, in the four iterative stages of NaaS service lifecycle management. These four iterative stages can be
categorized into design time, including design stage, and runtime execution time, including deployment
stage, operation stage and retirement stage.
Figure 8-1 depicts the metadata framework for NaaS service lifecycle management. The metadata of NaaS
service is created in design time, and then distributed to runtime execution time to be used in implementing
a metadata-driven service deployment, operation and retirement. The feedback from runtime execution
time to design time is to help identify the changes needed for the metadata.

Figure 8-1 – Metadata framework for NaaS service lifecycle management

8.1 Metadata of NaaS service in design time
Models of NaaS service, NaaS service operational policy, and NaaS resource are created and developed in
design time for making services and resources available, using modelling tools provided by NaaS CSP. The
modelling process will not trigger any NaaS service instantiation in the runtime execution environment until
the OSS-NaaS receives a request to do so.

The basic extendable model templates are defined and stored in service catalogue of OSS-NaaS (NaaS service
data model and NaaS service operational policy data model) and network controller (NaaS resource data
model) during design time and can be configured and extended with additional parameters, parameter value
ranges and validation rules according to NaaS CSC's request.

8.2 Metadata of NaaS service in runtime execution time
The modelled NaaS service is instantiated in runtime execution time and the specific NaaS service model and
its NaaS service operational policy data model drive the corresponding codes. The active NaaS service is
continuously monitored by event listening. The event, requiring healing and/or scaling based on real-time
NaaS CSC requests, is responded to based on the associated condition pre-defined in NaaS service
operational policy data model.
Based on the monitoring data collected during runtime execution time, the patterns governing usage,
thresholds, events, policy effectiveness, etc., are discerned and the necessary feedback to effect modelling
changes in design time is enabled.

518