LocalPKI: An Interoperable and IoT Friendly PKI

International audienceA public-key infrastructure (PKI) binds public keys to identities of entities. Usually, this binding is established through a process of registration and issuance of certificates by a certificate authority (CA) where the validation of the registration is performed by a registration authority. In this paper, we propose an alternative scheme, called LOCALPKI, where the binding is performed by a local authority and the issuance is left to the end user or to the local authority. The role of a third entity is then to register this binding and to provide up-to-date status information on this registration. The idea is that many more local actors could then take the role of a local authority, thus allowing for an easier spread of public-key certificates in the population. Moreover, LOCALPKI represents also an appropriate solution to be deployed in the Internet of Things context. Our scheme's security is formally proven with the help of Tamarin, an automatic verification tool for cryptographic protocols

A transactional multi-mode model to handle overload in distributed RTDBSs

noteCurrent applications, such as Web-based services, electronic commerce, mobile telecommunication systems, etc. are distributed in nature and manipulate time-critical databases. In order to enhance the performance and the availability of such applications, the major issue is to develop efficient protocols that cooperate with the scheduler to manage the overload of the distributed system. In order to help real-time database management systems (RTDBS) to maintain data logical consistency while attempting to enhance concurrency execution of transactions, we introduce a transactional multimode model to let the application transactions adapt their behavior to the overload consequences. In this paper, we propose for each transaction several execution modes and we derive an overload controller suitable for the proposed multimode model

Distributed Overload Control for Real-Time Replicated Database Systems

current applications such as Web-based services and electronic commerce use the technique of data replication. To take the replication benefit, we need to develop concurrency control mechanisms with high performance even when the distributed system is overloaded. In this paper, we present a protocol that uses a new notion called importance value which is associated with each realtime transaction. Under conditions of overload, this value is used to select the most important transactions with respect to the application transactions in order to pursue their execution; the other transactions are aborted. Our protocol RCCOS (Replica Concurrency-Control for Overloaded Systems) augments the protocol MIR-ROR, a concurrency control protocol designed for firm-deadline applications operating on replicated real-time databases in order to manage efficiently transactions when the distributed system is overloaded. A platform has been developped to measure the number of transactions that meet their deadlines when the processor load of each site is controlled.

Toward a real-time framework in cloudlet-based architecture

International audienc

How to Manage Replicated Real-Time Databases in an Overloaded Distributed System?

In order to meet their temporal constraints, current distributed applications such as Web-based services and electronic commerce use the technique of data replication. To take the replication benefit, we need to develop concurrency control mechanisms with high performance even when the distributed system is overloaded. In this paper, we present a protocol that uses a new notion called {\it importance value} which is associated with each realtime transaction. Under conditions of overload, this value is used to select the most important transactions with respect to the application transactions in order to pursue their execution; the other transactions are aborted. Our protocol RCCOS (Replica Concurrency-Control for Overloaded Systems) augments the protocol MIRROR, a concurrency control protocol designed for firm-deadline applications operating on replicated real-time databases in order to manage efficiently transactions when the distributed system is overloaded. A platform is currently being developed to measure the number of transactions that meet their deadlines when the processor load is controlled. Key-words: Firm real-time transactions, distributed database system, commit processing, processor overload, data replication. 1

Evaluation of Java card performance

With the growing acceptance of the Java card standard, understanding the performance behaviour of these platforms is becoming crucial. To meet this need, we present in this paper, a benchmark framework that enables performance evaluation at the bytecode and API levels. We also show, how we assign, from the measurements, a global mark to characterise the efficiency of a given Java Card platform, and to determine its performance according to distinct smart card profiles.Anglai

Measurement analysis when benchmarking Java Card platforms

The advent of the Java Card standard has been a major turning point in smart card technology. With the growing acceptance of this standard, understanding the performance behaviour of these platforms is becoming crucial. To meet this need, we present in this paper, a benchmark framework that enables performance evaluation at the bytecode level. This paper focuses on the validity of our time measurements on smart cards.Anglai