Page 195 - Trust in ICT 2017
P. 195

Trust in ICT                                                3






                       Service       Trust Agent    Trust Analysis and                          Service
                      Domain#1                   Management Platform(TAMP)            Other    Domain #2
                                         Trust
                                     TA                                               TAMPs     Domain
                                    Interface  Data   Trust Modelling & Evaluation             Specific Data
                                        Collecting
                         Social                     Social/Cyber/Physical
                         Data                         Trust Models
                                    Trust Data Filtering                                      .
                     Humans         and Preprocessing  Trust Reasoning and Evaluation         . .
                           Context
                           Data                     Trust Metric Extractor
                                                                          Trust
                          Cyber                                           Service               Service
                          Data                     Trust Repository & Gathering  Broker  Other  Domain #N
                      S/W,                           Trust Knowledge
                     Process  Domain                 Gathering Interfaces             TAMPs     Domain
                          Knowledge  Trust Service                                             Specific Data
                                      Enabler       Trust Data Repository
                         Physical   Trust  Trust
                          Data      Linking  IdM     Trust Computation
                      H/W,
                     Devices                          Data Analytics                             Trust
                                     Trust-based                                       Trust   Governance
                                    Recommendation   Cloud Computing                   API      Open data,
                                                                                              Knowledge Base

                       Figure 8-2 – An architectural framework for trust provisioning for ICT infrastructure
            8.2.1   Trust Agent (TA)
            TA  is  used  to  collect  trust-related  data  from  the  social-cyber-physical  environments  with  the  following
            modules.
                   TA Interface: TA provides lightweight interfaces to collect trust-related data from various types of
                    objects. Furthermore, TA interfaces need to be easily connected to existing platforms and devices
                    in order to extract the required data.
                   Trust Data Collection: This module is responsible for gathering the data required for evaluating a
                    trust level of an object. The Trust Analysis and Management Platform identifies the required trust
                    metrics for the object and informs to this module.
                   Trust Data Filtering and Pre-processing: This module is used to refine trust data sets without
                    including other data that can be repetitive, irrelevant or even sensitive for trust evaluation.
            8.2.2   Trust Analysis and Management Platform (TAMP)

            TAMP is used for modelling, reasoning and managing trust data collected from TAs to check whether social-
            cyber-physical objects satisfy certain trust criteria.
                   Trust Modelling: A trust model is used to specify, annotate and build trust relationships between
                    objects for the purpose of reasoning trust data. Trust modelling is social-cyber-physical and service
                    domain-specific, and there are social, cyber and physical trust models to define a trust model for
                    each domain in the ICT infrastructure. According to its domain and a particular service domain, a
                    suitable trust model is selected and applied for trust modelling. The trust-related data collected
                    from TAs can be transformed to structured and annotated formats by using semantic and ontology
                    technologies through this trust modelling module.
                   Trust Reasoning and Evaluation: Trust evaluation is used to analyse and assess trust levels based
                    on the trust model. There are various types of reasoning methods which depend on the social-
                    cyber-physical domains, and a proper reasoning method will be chosen for the specific object. For
                    example, policy-based trust reasoning makes a binary decision according to which an object is
                    trusted or not. Because trust status could change with time and circumstantial context, a trust
                    reasoning method must handle such dynamics of trust.
                   Trust Metric Extractor: The trust metric extractor recognizes trust characteristics, accounts for
                    factors influencing trust and determines proper trust metrics for the trust modelling and reasoning
                    by analysing the metadata or semantic ontologies.





                                                                                                         187
   190   191   192   193   194   195   196   197   198   199   200