Comparative Performance Evaluation of Syntax Structure of Digital Identifier Systems

Digital identifier systems are considered as one of the main areas of application in the identifiable Web approach in digital object theory. Based on the nature of these identifiers, which are based on the implementation of the resolution mechanism and also their differences from other identifiers, the syntax structure of these identifiers has particular importance. The syntax is a set of rules used to combine characters to form an identifier string. This study aims to evaluate the performance of the syntax structure of different digital identifier systems through an illustrative evaluation method and two sequential steps. In the first step, through a Delphi method, a framework was designed to evaluate the structure of systems’ syntax. The framework includes 11 performance indicators: Uniqueness, machine readability, stability, interoperability, simplicity, scalability, verifiability, granularity, character insensitivity, human readability, and syntax resolution. In the second step, 6 well-known global digital identifier systems were mapped in the framework and compared through an illustrative evaluation and TOPSIS methods. According to the findings, DOI (Digital object Identifier) and UCI (Universal Content Identifier) have a robust performance in their syntax structure and Handle, ARK (Archival Resource Key), URN (Uniform Resource Name) and PURL (Persistent Uniform Resource Locator) systems have mediocre performance in this component. Furthermore, the solutions of the robust performance systems in verification, including using the resolution mechanism, the TCP/ IP protocol, and the identifiers with check digits in the suffix, as well as the advantages of qualifiers, in particular, in the more precise identification of the Identified object are discussed. These results can be used by researchers of this field and administrators and users of these systems.