Using Metrics in the Industrial IoT Value Chain to Drive Trustworthiness
� Understand the nature of shortcomings and failures of a system component so that these can be mitigated within the system , or negotiated with the provider .
Figure 1 : The Value Chain of Industrial IoT
understanding the key considerations in a system and also aid in the analysis and design of a system , especially if historical metrics data is used to inform decisions . Clearly metrics can also be used during the operation of a system to maintain visibility into its operation and to help ensure that trustworthiness and other business and operational targets are met .
Good metrics will typically find many uses . For example , metrics on storage service reliability will help to :
� |
Clarify the expected service level and |
quality with any service providers . |
Metrics |
also |
support |
contractual |
enforcement such as assessment of |
penalties in case of failure to fulfill SLA |
( Service Level Agreement ) or SLO |
( Service Level Obligation ) targets , and |
support |
the |
ability |
to |
compare |
|
providers . |
|
|
|
|
� |
Evaluate |
how |
well |
the |
service |
performs . This in turn allows for |
precise feedback to providers . |
A real world example of this third point is a system where edge devices periodically invoke the cloud storage service directly every minute , while having the capacity to handle a backlog of only up to ten minutes of data stream . In this scenario , it is important to prevent downtimes of nine minutes or more of the data storage service . An adequate metric measuring the duration of downtimes – not just the uptime average – will be the basis for negotiating service quality in order to minimize data loss .
This paper describes how operational metrics data may be combined with business and risk management information to support a better understanding of trustworthiness , enabling investments made in trustworthiness to be better managed .
MANAGING TRUSTWORTHINESS
Trustworthiness in the business context means that a satisfactory level of confidence can be established in any system component ( be that a sensor , a machine or a factory ). Confidence can be established in what it claims to be , whether it fulfills its ascribed tasks , has appropriate performance , and will not endanger people , the environment , partners or the organization due to any issues relating to security , safety , reliability , resilience and privacy .
Tradeoffs and decisions need to be made among business and functional requirements as well as design decisions and
September 2018 - 89 -