Cross-Domain Discovery of Communication Peers. Identity Mapping and Discovery Services (IMaDS)

The upcoming WebRTC-based browser-to-browser communication services present new challenges for user discovery in peer-to-peer mode. Even more so, if we wish to enable different web communication services to interact. This paper presents Identity Mapping and Discovery Service (IMaDS), a global, scalable, service independent discovery service that enables users of web-based peer-to-peer applications to discover other users whom to communicate with. It also provides reachability and presence information. For that, user identities need to be mapped to any compatible service identity as well as to a globally unique, service-independent identity. This mapping and discovery process is suitable for multiple identifier formats and personal identifying properties, but it supports user-determined privacy options. IMaDS operates across different service domains dynamically, using context information. Users and devices have profiles containing context and other specific information that can be discovered by a search engine. The search results reveal the user's allocated globally unique identifier (GUID), which is then resolved to a list of the user's service domains identities, using a DHT-based directory service. Service-specific directories allow tracking of active endpoints, where users are currently logged on and can be contacted.Comment: Accepted for publication at the 2017 European Conference on Networks and Communications (EuCNC

Full-text Search for Verifiable Credential Metadata on Distributed Ledgers

Self-sovereign Identity (SSI) powered by distributed ledger technologies enables more flexible and faster digital identification workflows, while at the same time limiting the control and influence of central authorities. However, a global identity solution must be able to handle myriad credential types from millions of issuing organizations. As metadata about types of digital credentials is readable by everyone on the public permissioned ledger with Hyperledger Indy, anyone could find relevant and trusted credential types for their use cases by looking at the records on the blockchain. To this date, no efficient full-text search mechanism exists that would allow users to search for credential types in a simple and efficient fashion tightly integrated into their applications. In this work, we propose a full-text search framework based on the publicly available metadata on the Hyperledger Indy ledger for retrieving matching credential types. The proposed solution is able to find credential types based on textual input from the user by using a full-text search engine and maintaining a local copy of the ledger. Thus, we do not need to rely on information about credentials coming from a very large candidate pool of third parties we would need to trust, such as the website of a company displaying its own identifier and a list of issued credentials. We have also proven the feasiblity of the concept by implementing and evaluating a prototype of the full-text credential metadata search service