5 research outputs found
reclaimID: Secure, Self-Sovereign Identities using Name Systems and Attribute-Based Encryption
In this paper we present reclaimID: An architecture that allows users to
reclaim their digital identities by securely sharing identity attributes
without the need for a centralised service provider. We propose a design where
user attributes are stored in and shared over a name system under user-owned
namespaces. Attributes are encrypted using attribute-based encryption (ABE),
allowing the user to selectively authorize and revoke access of requesting
parties to subsets of his attributes. We present an implementation based on the
decentralised GNU Name System (GNS) in combination with ciphertext-policy ABE
using type-1 pairings. To show the practicality of our implementation, we
carried out experimental evaluations of selected implementation aspects
including attribute resolution performance. Finally, we show that our design
can be used as a standard OpenID Connect Identity Provider allowing our
implementation to be integrated into standard-compliant services.Comment: 12 page
On bitcoin security in the presence of broken cryptographic primitives
Digital currencies like Bitcoin rely on cryptographic primitives to operate. However, past experience shows that cryptographic primitives do not last forever: increased computational power and advanced cryptanalysis cause primitives to break frequently, and motivate the development of new ones. It is therefore crucial for maintaining trust in a cryptocurrency to anticipate such breakage. We present the first systematic analysis of the effect of broken primitives on Bitcoin. We identify the core cryptographic building blocks and analyze the ways in which they can break, and the subsequent effect on the main Bitcoin security guarantees. Our analysis reveals a wide range of possible effects depending on the primitive and type of breakage, ranging from minor privacy violations to a complete breakdown of the currency. Our results lead to several observations on, and suggestions for, the Bitcoin migration plans in case of broken or weakened cryptographic primitives
On bitcoin security in the presence of broken cryptographic primitives
Digital currencies like Bitcoin rely on cryptographic primitives to operate. However, past experience shows that cryptographic primitives do not last forever: increased computational power and advanced cryptanalysis cause primitives to break frequently, and motivate the development of new ones. It is therefore crucial for maintaining trust in a cryptocurrency to anticipate such breakage. We present the first systematic analysis of the effect of broken primitives on Bitcoin. We identify the core cryptographic building blocks and analyze the ways in which they can break, and the subsequent effect on the main Bitcoin security guarantees. Our analysis reveals a wide range of possible effects depending on the primitive and type of breakage, ranging from minor privacy violations to a complete breakdown of the currency. Our results lead to several observations on, and suggestions for, the Bitcoin migration plans in case of broken or weakened cryptographic primitives