Trust Score Overview

A trust score in Paragon Automation represents a level of trust in a network entity, expressed as a percentage, with 100% representing complete trust. A trust score is calculated based on the values of a list of factors, with contributions that reflect the relative significance of specific factors or groupings of factors.

A trust factor is any value of a network entity that can contribute to a trust score. The factors include metadata, such as identity, name, and description.

A factor category identifies the type of trust factor, such as prerequisite, variable, or reputational.

• Prerequisites—Conditions that a network target must meet to receive a non-zero trust score.

• Variable Contributions—Factors that provide a weighted trust contribution. You can assign weights based on nodes’ characteristics, such as configurations, versions, and active features. Variable trust changes could be due to discrete events resulting in step changes, for example, activating a feature or upgrading a node.

• Reputational Contributions—Incremental trust contributions earned over time. It is a cumulative function of specified historical events, for example, number of times a node was reconfigured or spontaneous reboots.

A score plan defines how to calculate a trust score for a network entity. It comprises a set of trust factors for each factor category.

The score plan also defines:

• Contribution values for each of the factors in the variable and reputational categories, describing the significance of the factor relative to other factors in the same category

• A weighting for the variable and reputational categories defining the percentages of the total trust score that each category contributes

A score plan is applied on a network entity by:

• Calculating the trust score based on the factors defined by the plan and the latest values of those factors for the network entity

• Generating and persisting a trust score result.

Contribution values are associated with the trust factors in a score plan. They are used to define the contribution of a factor to the calculation of the trust score. How contribution values are used depends on the type of trust factor with which those values are associated.

A trust factor has an implied maximum contribution and an actual contribution. The percentage score for a category, for example, the variable contribution is determined to be (the sum of the actual contributions for each of its factors/sum of the maximum contributions) * 100.

The overall percentage score is derived from the variable and reputational percentages, adjusted according to the category contribution weighting.