Since first introduced by Satoshi Nakamoto in 2008, Bitcoin has become the biggest and most well-known decentralized digital currency. Its anonymity allows users all over the world to make transactions with each other and keep their identities hidden. However, protecting private key becomes a very important issue because it is the only access to a unique account and can hardly be recovered if m...

Wireless sensor and actor networks are becoming more and more popular in the recent years. Each WSAN consists of numerous sensors and a few actors working collaboratively to carry out specific tasks. Unfortunately, actors are prone to failure due to harsh deployment environments and constrained power, which may break network connectivity resulting in disjoint components. Thus, maintaining the c...

In real-time systems, tasks have deadlines to be met despite the presence of faults. Primary-Backup (PB) scheme is one of the most common schemes that has been employed for fault-tolerant scheduling of real-time tasks, wherein each task has two versions and the versions are scheduled on two different processors with time exclusion. There have been techniques proposed for improving schedulabilit...

This article develops a model and analysis to provide insight into two effective remedies to increase supply chain resilience: (i) contracting with a secondary flexible backup supplier; and (ii) monitoring primary suppliers to obtain disruption risk information. To investigate the true value of these strategies, an analysis is performed under imperfect information concerning the disruption risk...

P2P architecture is a viable option for enterprise backup. In contrast to dedicated backup servers, nowadays a standard solution, making backups directly on organization’s workstations should be cheaper as existing hardware is used; more efficient as there is no single bottleneck server; and more reliable as the machines can be geographically dispersed. We present an architecture of a p2p backu...

As service providers move more applications to their IP/MPLS (Multiple Protocol Label Switching) networks, rapid restoration upon failure becomes more and more crucial. Recently MPLS fast reroute has attracted lots of attention as it was designed to meet the needs of real-time applications, such as voice over IP. MPLS fast reroute achieves rapid restoration by computing and signaling backup lab...

In real-time systems, tasks have deadlines to be met despite the presence of faults. Primary-Backup (PB) scheme is one of the most common schemes that has been employed for fault-tolerant scheduling of real-time tasks, wherein each task has two versions and the versions are scheduled on two different processors with time exclusion. There have been techniques proposed for improving schedulabilit...

This paper considers the following backup scheme for a database system: a database is updated at a nonhomogeneous Poisson process and an amount of updated files accumulates additively. To ensure the safety of data, full backup are performed at time NT=L or when the database fails, whichever occurs first, and between them, incremental backups are made at periodic times iT (i=1, 2, ..., N-1) so a...

Efficient planning plays a crucial role in model-based reinforcement learning. Traditionally, the main planning operation is a full backup based on the current estimates of the successor states. Consequently, its computation time is proportional to the number of successor states. In this paper, we introduce a new planning backup that uses only the current value of a single successor state and h...

In this paper we examine the potential bene ts of dedicated backup route(s) to provide survivability for ATM group communications. Specifically we examine the feasibility of providing survivability using working multipoint routes with disjoint dedicated backup multipoint routes where the multipoint routes are setup using either Virtual Rings, shared multicast trees, or VC Mesh groups. We introd...