This paper investigates a critical access control issue in the Internet of Things (IoT). In particular, we propose smart contract-based framework, which consists multiple contracts (ACCs), one judge contract (JC), and register (RC), to achieve distributed trustworthy for IoT systems. Each ACC provides method subject-object pair, implements both static right validation based on predefined policies dynamic by checking behavior subject. The JC misbehavior-judging facilitate ACCs receiving...

Efficient and reliable access control in smart cities is critical for the protection of various resources decision making task execution. Existing centralized schemes suffer from limitations single point failure, low reliability, poor scalability. This article, therefore, proposes a distributed framework by combining blockchain contract technology attribute-based (ABAC) model. The consists one policy management (PMC) managing ABAC policies, subject attribute (SAMC) attributes subjects (i.e.,...

Due to the rapid penetration of Internet Things (IoT) into human life, illegal access IoT resources (e.g., data and actuators) has greatly threatened our safety. Access control, which specifies who (i.e., subjects) can what objects) under conditions, been recognized as an effective solution address this issue. To cope with distributed trust-less nature systems, we propose a decentralized trustworthy Capability-Based Control (CapBAC) scheme by using Ethereum smart contract technology. In...

This paper investigates the fundamental issues of mode selection and spectrum partition in cellular networks with in-band device-to-device (D2D) communication from physical-layer security (PLS) perspective. We consider a scheme allowing each D2D pair to probabilistically switch between underlay overlay modes, also where system is orthogonally partitioned communications. first develop general theoretical framework model secrecy outage capacity performance users as well pairs. Optimization...

We develop a simple algorithm to compute the rate matrices of ergodic level-dependent quasi-birth-and-death processes, based on matrix continued fraction representation and probabilistic interpretation those matrices. The is easier implement less memory-consuming than that developed by Bright Taylor. apply an infinite-server queueing system with Markovian arrival process exponentially distributed service times. present some numerical results in order demonstrate efficiency our algorithm.

Millimeter-wave (mmWave) communications are highly promising to improve the capacity of modern wireless networks, while physical layer security (PLS) techniques hold great potential enhance critical secrecy performance therein. By carefully exploiting significant signal difference between Non-Light-of-Sight (NLoS) and Line-of-Sight (LoS) mmWave links, this paper proposes a Sight-based Cooperative Jamming (SCJ) scheme PLS ad hoc communications. In scheme, each jammer that has no LoS link its...

Recently, the rapid growth in both data center power density and scale poses great challenges to cooling system. On one hand, operators try over provision resources for fear of server failures induced by accumulated heat. other they also want reduce energy cost as system takes up a significant portion overall consumption. Among all available solutions, air dominates industry due its simpleness. However, efficiency has been questioned low specific In this paper, we provide an overview current...

The large-scale and trustless nature of the Internet Things (IoT) calls for distributed trustworthy access control schemes to prevent unauthorized resource access. This paper proposes a Capability-Based Access Control (CapBAC) scheme by applying emerging Ethereum blockchain technology. uses smart contracts, i.e., executable codes residing in blockchain, store manage capability tokens, special data structures that maintain allowed actions user (i.e., subject) on certain object). To provide...

In Bitcoin system, transactions are prioritized according to transaction fees. Transactions without fees given low priority and likely wait for confirmation. Because the demand of micro payment in is expected increase due remittance cost, it important quantitatively investigate how with small affect transaction-confirmation time. this paper, we analyze time by queueing theory. We model process as a system batch service, deriving mean Numerical examples show affects also consider effect...

Access control has been recognized as a critical issue for preventing unauthorized access to the resources in Internet of Things (IoT) systems. This paper proposes an Attribute-Based Control (ABAC) framework IoT systems by using emerging Ethereum smart contract technology. The consists one Policy Management Contract (PMC), Subject Attribute (SAMC), Object (OAMC) and (ACC). PMC, SAMC OAMC are responsible storing managing ABAC policies, attributes subjects (i.e., entities accessing resources)...

Unauthorized resource access represents a typical security threat in the Internet of Things (IoT), while distributed ledger technologies (e.g., blockchain and IOTA) hold great promise to address this threat. Although blockchain-based IoT control schemes have been most popular ones, they suffer from several significant limitations, such as high monetary cost low throughput processing requests. To overcome these paper proposes novel scheme by combining fee-less IOTA technology...

This paper considers a state-dependent M/M/$c$/$c+r$ retrial queuewith Bernoulli abandonment, where the number of servers is equal to$c$, capacity buffer to $r$ and that thevirtual waiting room (called orbit) for customers infinite.We assume arrival,service rates depend on in thesystem (the buffer).In this paper, we first present ergodic conditionfor our queue. Then, by continued fraction approach, wederive analytical solutions stationary joint distribution ofthe queue lengths system orbit,...

<p style='text-indent:20px;'>In Bitcoin system, a transaction is given priority value according to its attributes such as the remittance amount and fee, transactions with high priorities are likely be confirmed faster than those low priorities. In this paper, we analyze transaction-confirmation time for system. We model process queueing system batch service, M/<inline-formula><tex-math id="M1">\begin{document}$ \mbox{G}^B $\end{document}</tex-math></inline-formula>/1. consider joint...

With the rapid dissemination of Internet Things (IoT), number resources deployed in IoT systems such as devices and data is growing explosively. Since often handle private information, it essential to enforce appropriate access control prevent unauthorized access. However, conventional schemes which rights are stored a centralized server prone load concentration single point failure. Although distributed leveraging blockchain technologies have been proposed deal with problems, they inherit...

This paper studies M/M/$c$/$c$ retrial queues, where $c$ servers areall identical. In the an arriving customer is servedimmediately if it finds idle server upon arrival, otherwise thecustomer tries to enter system after exponentially distributedtime independently of other customers. As well known, achallenging problem obtain analytical solution for stationaryjoint distribution numbers customers and busyservers in queue especially $c \ge3$. Under some technical assumptions, a few solutions...

In cloud computing, a large-scale parallel-distributed processing service is provided where huge task split into number of subtasks and those are processed on cluster machines called workers. such service, worker which takes long time for subtask makes the response (the issue stragglers). One efficient methods to alleviate this execute same by another in preparation slow (backup tasks). paper, we consider efficiency backup tasks. We model task-scheduling server as single-server queue,...

In this article, we propose zero-knowledge named proof, a stateless replay attack prevention strategy that ensures the user’s anonymity against malicious administrators. We begin with adopting set-membership proof into an authentication setting in which users would delegate their requests to agent obstructs identity from administrator. This anonymous carries guarantee of authenticity, administrator through can confirm. Next, prevent attacks other parties by binding agent’s verifiable By...

This paper considers MAP/G/1 queueing systems under the following two situations: (1) At end of a busy period, server is turned off and inspects queue length every time customer arrives. When reaches pre-specified value N, turns on serves customers continuously until system becomes empty. (2) takes sequence vacations. each vacation, length. If greater than or equal to N at this time, begins serve For case, we analyze stationary actual waiting distributions, derive recursive formulas compute...