An Architecture for Biometric Electronic Identification Document System Based on Blockchain This paper proposes an architecture for biometric electronic identification document (eID) system based on Blockchain for citizens identity verification in transactions corresponding to the notary, registration, tax declaration and payment, basic health services and registration of economic activities, among others. To validate the user authentication, a biometric eID system is used to avoid spoofing and related attacks. Also, to validate the document a digital certificate is used with the corresponding public and private key for each citizen by using a userxe2x80x99s PIN. The proposed transaction validation process was implemented on a Blockchain system in order to record and verify the transactions made by all citizens registered in the electoral census, which guarantees security, integrity, scalability, traceability, and noambiguity. Additionally, a Blockchain network architecture is presented in a distributed and decentralized way including all the nodes of the network, database and government entities such as national register and notary offices. The results of the application of a new consensus algorithm to our Blockchain network are also presented showing mining time, memory and CPU usage when the number of transactions scales up.

Blockchain Applied to Vehicular Odometers Fraud in automobile odometers is a billion dollar problem worldwide. The technical requirements behind any solution for this problem go through the perennial, secure, and immutable registration of vehicular data. Such requirements immediately raise the question of how blockchain technology could be used for this purpose. In this article, the requirements, design choices, and construction details of a blockchain architecture for vehicular odometers are presented and discussed. The architecture advances the state of the art by adopting a more efficient consensus algorithm than the traditional ones, such as proof of work. Results from a prototype proof ofconcept of the proposed architecture validate the solution, which is able to validate a new block in the blockchain every two seconds. Applicability in real scenarios is one step ahead and very promising.