Page 258 - Trust in ICT 2017

5 Trust in ICT

objective trust indicators and the objectified subjective trust indicators which are objectified for
calculation. A trust index evaluates and quantifies trustworthiness of trustee.

For trust evaluation as shown in Figure 6, it is needed to collect data from various sources. Collected data are
categorized into two trust attributes, i.e., qualitative and quantitative attributes. Trust attributes are self-
accumulated from the inputs of various sources. Trust attributes are used to calculate trust indicators. Trust
indicators also have the self-accumulated properties from subjective and/or objectives attributes. It notes
that the time-varying behaviours of trust indicators also appeared by accumulation of every new instance. A
trust index is calculated by the self-accumulated manner with combination of objective trust indicators and
subjective trust indicators. The trustor finally makes a decision with a certain a trust value. A trust value
represents a numerical quantity decide an entity’s trust in a trustor’s perspective. Based on trust indicators
and trust index about the entity, the trustor obtains a trust value of the entity to make a decision.

Figure 6 – Trust evaluation for trust provisioning

8 Trust provisioning processes
Trust provisioning in ICT infrastructures and services consists of a set of processes, which include gathering
data from entities, producing and distributing trust information by evaluating all aspects of trust, to support
entities’ decision making for establishing trust relationship with other entities. This clause describes trust
provisioning processes as follow: i) data collection, ii) data management, iii) trust information analysis, iv)
dissemination of trust information, and v) trust information lifecycle management.

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