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In this paper, a novel management framework for fog computing with strategic computing speed control at fog nodes (FNs) is studied. In the considered model, mobile users declare requests of offloading resource-hungry computation tasks that are dynamically collected at a dedicated edge server (ES). Upon receiving these requests, the ES can decide to either self-process or delegate some workloads to third-party FNs for maximizing the overall management profit. Unlike the existing work, this paper takes into account strategic behaviors of FNs in computing speed control, i.e., each FN can strategically allocate its computing resource to maximize its utility, which consists of the benefit gained from executing offloaded tasks and the cost incurred by dissatisfied (delayed) service to its own subscribed tasks. To jointly address the long-term system performance and FNs strategic interactions, a scheduling mechanism integrating a noncooperative game and a queueing model is formulated. We then investigate two delegation reward settings, i.e., constant and utility-dependent delegation prices, and propose efficient adaptive algorithms to determine the optimal workload distribution at the ES and the computing speed equilibrium among FNs. Both theoretical analyses and simulations are conducted to evaluate the performance of the proposed solutions and demonstrate their superiorities over counterparts.

This paper considers the challenging problem of establishing deadlock freedom for message-passing processes using behavioral type systems. In particular, we consider the case of processes that implement session types by communicating asynchronously in cyclic process networks. We present APCP, a typed process framework for deadlock freedom which supports asynchronous communication, delegation, recursion, and a general form of process composition that enables specifying cyclic process networks. We discuss the main decisions involved in the design of APCP and illustrate its expressiveness and flexibility using several examples., Comment: In Proceedings ICE 2021, arXiv:2109.14908. arXiv admin note: text overlap with arXiv:2101.09038

We consider the verifiable problem of delegation computing in cloud, which means a client needs to outsource a computing function to untrusted servers, and verify the returned computational results. A recently related result of Dong et al. (CCS 2017) shows a client outsources the same computation task to two different servers, which achieves verifiability by simply cross-checking. In Dong’s replication-based scheme, although the expensive cryptographic algorithms for verification is not needed, the delegation overhead is double. In order to reduce delegation overhead of Dong’s scheme, we propose a novel incentive-compatible rational delegation computing scheme. Specifically, the client sends duplicate tasks to some servers for cross-checking, meanwhile, each sever only knows the probability distribution of receiving a duplicate task. Furthermore, considering rational delegation computing as a dynamic game with imperfect information , we design reasonable and effective incentive mechanisms. Afterwards, we seek a unique sequential equilibrium in each game, and strictly prove that rational players still have no motivation to deviate from honest behavior under a condition of lower delegation overhead. Detailed analysis indicates that the lowest delegation overhead achieved by our scheme is only n 2 n - 2 of that achieved by Dong’s scheme, where n means the number of servers.

Today’s API are used for a variety of things such as passing data to another webservice, reading data from a database etc. The problem with this is that not all the API`s are secure. Most of the todays API are old and rely only on an authentication token or string which is often hardcoded. We will focus on OAUTH 2.0 as a new protocol in securing our API`s. This is a new protocol based on delegation of authorization, dynamically changing authentication string based on user session or application session. We will go on this different modes of authentication and show you how to use them properly. We will set up this with a Web Api integrated with OAUTH and a client application that will stimulate the requests to our API.

International audience; A future is an entity representing the result of an ongoing computation. A synchronisation with a "get" operation blocks the caller until the computation is over, to return the corresponding value. When a computation in charge of fulfilling a future delegates part of its processing to another task, mainstream languages return nested futures, and several "get" operations are needed to retrieve the computed value (we call such futures "control-flow futures"). Several approaches were proposed to tackle this issues: the "forward" construct, that allows the programmer to make delegation explicit and avoid nested futures, and "data-flow explicit futures" which natively collapse nested futures into plain futures. This paper supports the claim that data-flow explicit futures form a powerful set of language primitives, on top of which other approaches can be built. We prove the equivalence, in the context of data-flow explicit futures, between the "forward" construct and classical "return" from functions. The proof relies on a branching bisimulation between a program using "forward" and its "return" counterpart. This result allows language designers to consider "forward" as an optimisation directive rather than as a language primitive. Following the principles of the Godot system, we provide a library implementation of control-flow futures, based on data-flow explicit futures implemented in the compiler. This small library supports the claim that the implementation of classical futures based on data-flow ones is easier than the opposite. Our benchmarks show the viability of the approach from a performance point of view.

In IPFS content identifiers are constructed based on the item's data therefore the binding between an item's identifier and its data can be deterministically verified. Nevertheless, once an item is modified, its identifier also changes. Therefore when it comes to mutable content there is a need for keeping track of the "latest" IPFS identifier. This is achieved using naming protocols on top of IPFS, such as IPNS and DNSlink, that map a constant name to an IPFS identifier, allowing at the same time content owners to update these mappings. Nevertheless, IPNS relies on a cryptographic key pair that cannot be rotated, and DNSlink does not provide content authenticity protection. In this paper, we propose a naming protocol that combines DNSlink and decentralized identifiers to enable self-verifiable content items. Our protocol provides content authenticity without imposing any security requirement to DNSlink. Furthermore, our protocol prevent fake content even if attackers have access to the DNS server of the content owner or have access to the content owner secret keys. Our proof of concept implementation shows that our protocol is feasible and can be used with existing IPFS tools., Comment: In: DI2F: Decentralising the Internet with IPFS and Filecoin, IFIP Networking 2021 workshop

Blind quantum computing enables a client, who can only generate or measure single-qubit states, to delegate quantum computing to a remote quantum server in such a way that the input, output, and program are hidden from the server. It is an open problem whether a completely classical client can delegate quantum computing blindly. In this paper, we show that if a completely classical client can blindly delegate sampling of subuniversal models, such as the DQC1 model and the IQP model, then the polynomial-time hierarchy collapses to the third level. Our delegation protocol is the one where the client first sends a polynomial-length bit string to the server and then the server returns a single bit to the client. Generalizing the no-go result to more general setups is an open problem., Comment: 19 pages, 2 figures

Key regression is a primitive that allows a content publisher to give a small amount of keying material, for time stamp i, to a party such that they can derive key k i and all keys k j for time stamps j i , but not for time stamps j > i . Existing key-regression schemes based on random oracles, pseudorandom permutations, and pseudorandom generators require a publisher to maintain state of size linear in the number of potential keys. In previous work, constant sized publisher state has only been accessible through the use of trapdoor permutations (e.g., RSA). This paper presents a novel key-regression scheme where the publisher must store only a constant amount of state information without trapdoor permutations. This is achieved through the use of constrained pseudorandom functions, a primitive that allows for the delegation of partial evaluation without revealing the key.

Background: Oral antiproliferative therapies have become increasingly important in the treatment of tumors. To ensure patient safety, medical care is focused on adherence and side effects. Objectives: To meet increased personnel and time requirements, delegation of tasks to nonmedical specialists (NMS) may be a solution; however, presently, little is known about the options in Germany. Method: At least 3,300 members of the German Society for Hematology and Medical Oncology (DGHO), 580 members of the Professional Association of Office-Based Hematologists and Oncologists in Germany (BNHO), and 1,500 members of the Conference on Oncology Nursing and Pediatric Nursing (KOK) were contacted via a web-based survey. The survey focused on the feasibility of oncology nurse consultation as an additional consulting service for patients undergoing oral tumor therapy. Results: In total, 255 (physicians) and 206 (NMS) questionnaires were evaluable; 90.9% of the physicians were hematologists/oncologists, 87.8% advocated oncology nurse consultation, 34.1% had previously implemented/scheduled such consultations, 58.3% of the NMS were nursing staff, 46.1% had advanced training in oral tumor therapy, 94.2% were interested in further qualifications, 37.8% worked at facilities with established/planned nurse consultations, and 62.1% personally conducted/preferred conducting consultations. Conclusions: Throughout Germany, there seems to exist a group of qualified NMS who are motivated to provide care to patients undergoing oral tumor therapy. Particular physicians actively support these nurse consultations. Extensive implementation of delegation concepts in standard care of patients undergoing oral tumor therapy is not yet underway.

A protocol for directed digital signature is proposed on isogenies of elliptic curves, in which only a specific recipient, whose signature key was used to generate the signature, can verify the signature. The sender and recipient of the message control the delegation of the right to verify the received signature.

We consider the problem of verifiable and private delegation of computation [Gennaro et al. CRYPTO’10] in which a client stores private data on an untrusted server and asks the server to compute functions over this data. In this scenario we aim to achieve three main properties: the server should not learn information on inputs and outputs of the computation (privacy), the server cannot return wrong results without being caught (integrity), and the client can verify the correctness of the outputs faster than running the computation (efficiency). A known paradigm to solve this problem is to use a (non-private) verifiable computation (VC) to prove correctness of a homomorphic encryption (HE) evaluation on the ciphertexts. Despite the research advances in obtaining efficient VC and HE, using these two primitives together in this paradigm is concretely expensive. Recent work [Fiore et al. CCS’14, PKC’20] addressed this problem by designing specialized VC solutions that however require the HE scheme to work with very specific parameters; notably HE ciphertexts must be over \(\mathbb {Z}_q\) for a large prime q.

Proxy re-encryption (PRE), introduced by Blaze, Bleumer, and Strauss at EUROCRYPT 98, offers delegation of decryption rights, i.e., it securely enables the re-encryption of ciphertexts from one key to another, without relying on trusted parties. PRE allows a semi-trusted third party termed as a “proxy” to securely divert ciphertexts of a user (delegator) to another user (delegatee) without revealing any information about the underlying messages to the proxy. Attribute-based proxy re-encryption (ABPRE) generalizes PRE by allowing such transformation of ciphertext under an access-policy into another ciphertext under a new access policy. Such a primitive facilitates fine-grained secure sharing of encrypted data in the cloud.

The Kotlin type system is comprised of more than just classes and objects; it includes interfaces and enumerated types. In this chapter we will explore the concept of an interface and what components can be defined within an interface. We will also consider a Kotlin language facility that allows an interface to be implemented via delegation. The chapter concludes by looking at enumerated types. An enumerated type is a type consisting of a set of named values also called elements or members of the enumeration. These values have a specific name and an ordering.

Since 2017, the Worldwide LHC Computing Grid (WLCG) has been working towards enabling token based authentication and authorisation throughout its entire middleware stack. Following the publication of the WLCG Common JSON Web Token (JWT) Schema v1.0 [1] in 2019, middleware developers have been able to enhance their services to consume and validate the JWT-based [2] OAuth2.0 [3] tokens and process the authorization information they convey. Complex scenarios, involving multiple delegation steps and command line flows, are a key challenge to be addressed in order for the system to be fully operational. This paper expands on the anticipated token based workflows, with a particular focus on local storage of tokens and their discovery by services. The authors include a walk-through of this token flow in the RUCIO managed data-transfer scenario, including delegation to FTS and authorised access to storage elements. Next steps are presented, including the current target of submitting production jobs authorised by Tokens within 2021.

Leadership is the ability and readiness of a person to be able to influence, encourage, invite, guide, move others in order to help achieve certain goals. Leadership is essentially related to organized human labor, and as a power or potential. The purpose of this study aims to describe and analyze the role of leadership in Islamic educational institutions. This research method uses a library research approach (library research). The results of this study indicate that the leadership function is; 1) Instruction function; 2) Consultation function; 3) Participation function; 4) Delegation function; and 5) control function. The role of the leader is; a) Future leaders must be flexible and have extensive experience; b) As head of the organization, it becomes a necessary function, not something trivial that must be delegated to others; and c) Policy making is no longer effective at the top of the organization.

The ubiquitous nature of IoT devices has brought new and exciting applications in computing and communication paradigms. Due to its ability to enable auto-configurable communication between IoT devices, pervasive applications, and remote clients, the use of the Universal Plug and Play (UPnP) protocol is widespread. However, the advertisement and discovery mechanism of UPnP incurs significant overhead on resource-constrained IoT devices. In this paper, we propose a delegation-based approach that extends the UPnP protocol by offloading the service advertisement and discovery-related overhead from resource-limited IoT devices to the resource-rich neighbours of a UPnP-enabled IoT network. Our experimental evaluations demonstrate that the proposed scheme shows significant improvement over the basic UPnP, reducing energy consumption and network overhead.

In cloud computing, the delegation computation service is required because end users usually are resource-constrained, and at the same time the correctness of computing results needs to be verified. However, all the existing and available technologies have a high cost to verify which is the main problem faced by the delegation computing under the cloud platform. In order to address this issue, based on the game theory and a smart contract, we construct three protocols. The client and the calculator sign the Prisoner's Protocol to incentivize correct computation by asking the calculator to pay a deposit upfront; The client and the verifier sign the Long-acting Mechanism Protocol to ensure the validity of the verification results; The calculator and the verifier sign the Collusion Protocol to make collusion the most profitable strategy for all colluding parties. Through the combination of these protocols, the work is realized by separation the computing task and the verification task, and the heavy verification task is avoided. Finally, the performance analysis of the results shows that the combination of all the protocols not only solves the problem of verification complexity in the traditional delegation computing, but also guarantees the benefit of the honest player.

Mining software repositories at a large scale typically requires substantial computational and storage resources. This creates an increasing need for repository mining programs to be executed in a distributed manner, such that remote collaborators can contribute local computational and storage resources. In this paper we present Crossflow, a novel framework for building polyglot distributed repository mining programs. We demonstrate how Crossflow offers delegation of mining jobs to remote workers and can cache their results, how such workers are able to implement advanced behavior like load balancing and rejecting jobs they either cannot perform or would execute sub-optimally, and how workers of the same analysis program can be written in different programing languages like Java and Python, executing only relevant parts of the program described in that language.

Hypervisor implementations such as XMHF, Nova, PROSPER, prplHypervisor, the various L4 descendants, as well as KVM and Xen offer mechanisms for dynamic startup and reconfiguration, including the allocation, delegation and destruction of objects and resources at runtime. Some use cases such as cloud computing depend on this dynamicity, yet its inclusion also renders the state space intractable to simulation-based verification tools. On the other hand, system architectures for embedded devices are often fixed in the number and properties of isolated tasks, therefore a much simpler, less dynamic hypervisor design would suffice. We close this design gap by presenting Phidias, a new hypervisor consisting of a minimal runtime codebase that is almost devoid of dynamicity, and a comprehensive compile-time configuration framework. We then leverage this lack of dynamic components to non-interactively verify the validity of certain invariants. Specifically, we verify hypervisor integrity by subjecting the compiled hypervisor binary to our own symbolic execution engine. Finally, we discuss our results, point out possible improvements, and hint at unexplored characteristics of a static hypervisor design.

AIM This study aims to determine the effectiveness of home-based pelvic floor muscle training (PFMT) on decreasing the severity of symptoms and improving the quality of life (QOL) among Omani women with stress urinary incontinence (SUI). METHODS A randomized controlled single-blind trial was conducted in three primary health care centers in Muscat. Eligible women who were diagnosed with SUI (from a concurrent phase-I study which was a cross-sectional study to determine the prevalence of urinary incontinence in Oman) were invited to take part. The consenting subjects were randomly allocated to either an intervention group (unsupervised PFMT) or a control group (lecture with no PFMT). Baseline and 12-week assessment of both groups was carried out for the primary outcome using the validated Arabic version of the International Consultation on Incontinence Questionnaire (ICIQ)-short form and the secondary outcome by blinded measures of pelvic floor muscle (PFM) strength using the modified Oxford grading system (MOGS), endurance, and perineometer. RESULTS A total of 73 subjects were included in the study. They were randomly divided into two groups. Both groups were similar at the baseline in terms of sociodemographic characteristics, ICIQ score, and PFM strength. At the 12-weeks assessment, there was a significant difference in the ICIQ score (P

We propose SessionC#, a lightweight session typed library for safe concurrent/distributed programming. The key features are (1) the improved fluent interface which enables writing communication in chained method calls, by exploiting C#'s out variables, and (2) amalgamation of session delegation with async/await, which materialises session cancellation in a limited form, which we call session intervention. We show the effectiveness of our proposal via a Bitcoin miner application., Comment: In Proceedings PLACES 2020, arXiv:2004.01062

Improved filter permutators are designed to build stream ciphers that can be efficiently evaluated homomorphically. So far the transciphering with such ciphers has been implemented with homomorphic schemes from the second generation. In theory the third generation is more adapted for the particular design of these ciphers. In this article we study how suitable it is in practice. We implement the transciphering of different instances of the stream cipher family FiLIP with homomorphic encryption schemes of the third generation using the TFHE library. We focus on two kinds of filter for FiLIP. First we consider the direct sum of monomials, already evaluated using HElib and we show the improvements on these results. Then we focus on the XOR-threshold filter, we develop strategies to efficiently evaluate any symmetric Boolean function in an homomorphic way, allowing us to give the first timings for such filters. We investigate different approaches for the homomorphic evaluation: using the leveled homomorphic scheme TGSW, an hybrid approach combining TGSW and TLWE schemes, and the gate boostrapping approach. We discuss the costs in time and memory and the impact on delegation of computation of these different approaches, and we perform a comparison with others transciphering schemes.

This specification defines a protocol for an HTTP- and JSON- based Security Token Service (STS) by defining how to request and obtain security tokens from OAuth 2.0 authorization servers, including security tokens employing impersonation and delegation.

In this work, we construct an updatable and unambiguous delegation scheme based on the decisional assumption on bilinear groups introduced by Kalai, Paneth and Yang [STOC 2019]. Using this delegation scheme, we show PPAD-hardness (and hence the hardness of computing Nash equilibria) based on the quasi-polynomial hardness of this bilinear group assumption and any hard language that is decidable in quasi-polynomial time and polynomial space.

Delegation computing is a calculation protocol between non-cooperative participants, and its results are influenced by the participant’s choice of behavior. The goal of this paper is to solve the problem of high communication overhead in traditional delegation computing schemes. Combining the advantages of information theory and game theory, we propose a rational delegation computing scheme, which guarantees the correctness of the calculation results through the participant utility function. First, by analyzing the participant behavior strategy, we design the game model, which includes the participant set, information set, behavior strategy set and utility function. Second, according to the combination of Nash equilibrium and channel capacity limit in the game model, we construct a rational delegation computing scheme in this paper. Finally, we analyze and prove the scheme. When both the delegation party and computing party choose the honesty strategy, their utility reaches the maximum, that is, the global can reach the Nash equilibrium state, and the calculation efficiency has also been improved.

The paper is devoted to the development of principles and operation algorithms of blockchain-based metadata driven data management system in distributed computing environments with partial or complete lack of trust between user groups belonging to different administrative domains. We also suggest a new method for delegation of rights from a user or service to another service within distributed computing systems. The implementation of the proposed approach, entitled ProvHL, is based on the permissioned blockchains and on the Hyperledger Fabric blockchain platform.

With the rapid development of group-oriented services, there are more and more multi-group communications in which users may join multiple group communications simultaneously. For example, in a wireless body area network (WBAN), medical personnels get together to hold a consultation for the patient and multiple consultation groups co-existed at the same time. A doctor may join more than one consultation groups simultaneously. Most existing group key establishment schemes establish a single group key for a single group. Applying a conventional group key establishment scheme in a straightforward manner (that is, running many times) can provide group-key-oriented multi-group key establishments. Since most group key establishment schemes suffer from larger rekeying overheads if users depart or join the network frequently, it is obvious that these schemes are not suitable for multiple groups co-existing applications such as WBAN. In this paper, we define a new type of user-oriented multi-group key establishments using secret sharing (UMKESS) for secure communications in WBAN. Since health data are private and sensitive information, efficient and secure data transmission in cloud-assisted WBANs is needed. In our proposed UMKESS, each user keeps only one share and uses the share to join multiple groups simultaneously, that is, or achieve multiple things at one stroke. Furthermore, the key generation center can manage user departing or joining dynamically with no rekeying overhead. The security strength of UMKESS is discussed in detail. In comparing to the latest group-key-oriented multi-group key establishment using secret sharing, UMKESS significantly improves the effectiveness of the multi-group communications and it is desirable for WBAN.

It has been almost one and a half decades since the introduction of the concept of hierarchical identity-based encryption (HIBE) systems, and many pairing-based HIBE systems have been proposed; however, how to achieve independent private key delegation in HIBE systems is still open. Independent private key delegation in HIBE systems requires that the following three conditions are satisfied: (1) private keys are not valid delegation credentials for deriving descendants’ private keys, (2) any entity intending to derive a private key for any one of its descendants should own a valid delegation credential distributed by the root private key generator (PKG), and (3) a credential is only valid for deriving private keys for a given descendant. We present a new technique for composing private keys for entities in HIBE systems that we call identifier discrimination, aiming at resolving the problem of independent private key delegation. With the technique, we construct a selective identity secure HIBE system under the decisional bilinear Diffie–Hellman (DBDH) assumption in the standard model with the following properties. (1) Every entity in the HIBE system is prevented from deriving private keys for its descendants with the only use of its private key and the public parameters. (2) The root PKG can delegate the privilege (if needed) of generating private keys for each individual entity to any of its ancestors through authorization that we call authorized delegation, by distributing a specifically crafted secret (delegation credential) to the ancestor. (3) The encryption privacy of each ciphertext for its intended recipient is achieved, that is, ciphertexts encrypted on identity of any entity cannot be decrypted by any of its ancestors that we call dedicated encryption privacy.

In this paper, we study the two fundamental functionalities oblivious polynomial evaluation in the exponent and set-intersection and introduce a new technique for designing efficient secure protocols for these problems (and others). Our starting point is the technique (Benabbas et al. in CRYPTO, 2011) for verifiable delegation of polynomial evaluations, using algebraic PRFs. We use this tool, that is useful to achieve verifiability in the outsourced setting, in order to achieve privacy in the standard two-party setting. Our results imply new simple and efficient oblivious polynomial evaluation (OPE) protocols. We further show that our OPE protocols are readily used for secure set-intersection, implying much simpler protocols in the plain model. As a side result, we demonstrate the usefulness of algebraic PRFs for various search functionalities, such as keyword search and oblivious transfer with adaptive queries. Our protocols are secure under full simulation-based definitions in the presence of malicious adversaries.

Outsourcing computation with verifiability is a merging notion in cloud computing, which enables lightweight clients to outsource costly computation tasks to the cloud and efficiently check the correctness of the result in the end. This advanced notion is more important in marine mobile computing since the oceangoing vessels are usually constrained with less storage and computation resources. In such a scenario, vessels always firstly outsource data set and perform a function computing over them or at first outsource computing functions and input data set into them. However, vessels may choose which delegation computation type to outsource, which generally depends on the actual circumstances. Hence, we propose a scalable verifiable outsourcing computation protocol (SV-OC) in marine cloud computing at first and extract a single-mode version of it (SM-SV-OC), where both protocols allow anyone who holds verification tokens to efficiently verify the computed result returned from cloud. In this way, the introduced “scalable” property lets vessels adjust the protocol to cope with different delegation situations in practice. We additionally prove both SV-OC and SM-SV-OC achieving selective soundness in the random oracle model and evaluate their performance in the end.

The Internet of Things (IoT) supports many users and context‐aware applications controlling heterogeneous IoT devices. This differs from traditional networks, in which a single entity manages each device. Thus, new access control models must be created in order to support more responsive, scalable, secure, and autonomous management. This article presents an attribute‐based access control model, which applies conflict resolution and access delegation in a multiuser and multiapplication environment. With scalability in mind, we propose the caching of access permissions, as well as a split policy processing model in which the devices with enough computational power perform part of the processing. The proposed model was implemented as part of the ManIoT architecture an d evaluated in experiments on a testbed to demonstrate its efficiency. Results show that our model accelerates the processing of access management policies from 51% by up to 79%.

We present a behavioural typing system for a higher-order timed calculus, using session types to model timed protocols, and the calculus to abstract implementations. Behavioural typing ensures that processes in the calculus will perform actions in the time-windows prescribed by their protocols. We introduce duality and subtyping for timed asynchronous session types. Duality includes a class of protocols that previous work on asynchronous timed session types could not type-check. Subtyping is critical for precision of our typing system, especially for\ud session delegation. The composition of dual (timed asynchronous) types enjoys progress when using an urgent receive semantics, in which receive actions are executed as soon as the expected message is available. Our calculus increases the modelling power of calculi used in the previous work on timed sessions, adding a blocking receive primitive with timeout, and a primitive that consumes an arbitrary amount of time in a given range.

The paper suggests a new approach based on blockchain technology and smart contracts to delegation of rights within distributed computing systems, which is fault-tolerant, safe and secure. The implementation of the proposed approach is based on the permissioned blockchains and on the Hyperledger Fabric blockchain platform in conjunction with Hyperledger Composer.

The Disarmament Conference reconvened 2 February 1933, whereupon it proceeded to examine the French Constructive Plan and a British proposal for a convention based on a synthesis of all the proposals submitted of which there had been acceptance. It soon became clear that the conference had reached a deadlock in light of German rearmament plans and France’s concern for its security. Fearing that the conference would collapse and that an unregulated arms race would ensue, the British delegation produced a provisional draft convention which provided for more disarmament than under the French plan and to which they hoped Germany would bind itself in preference to being condemned by world opinion. For its critics, however, the so-called MacDonald Plan of 16 March, which proposed that its terms replace the disarmament provisions of the peace treaties, was a rearmament convention. That it provided only for consultation among the powers should there arise a violation or threatened violation of the Pact of Paris, was wholly unsatisfactory for many in France. In attacking the plan on 23 March, Churchill declared, ‘Thank God for the French army,’ and went on to warn that revision of the peace treaties at that time was ‘appallingly dangerous.’

Primary adenoid cystic carcinoma (ACC) of the trachea with thyroid invasion is very rare. In this report, we present a 46-year-old man with primary ACC of the trachea with thyroid invasion. ACC invasion of the thyroid is very rare and is easily misdiagnosed. The patient sought consultation due to a 6-month history of dysphagia and associated dyspnea. A contrast-enhanced computed tomography scan obtained at the time of admission revealed bilateral thyroid masses and tracheal wall thickening. The thyroid masses were fused to the trachea and the esophagus without discernible borders, intraoperatively. Frozen pathology suggested poorly differentiated cancer, and a bilateral partial thyroidectomy was performed. Postoperative pathology revealed primary tracheal ACC with thyroid invasion. The patient died 1 month after surgery. We have also summarized the literature on the clinical presentation, diagnosis, and treatment of thyroid-invasive ACC.

As Hierarchical Identity Based Encryption (HIBE) system usually maps the true institutional structure of an organization or entity relationship between objects in real world, It is important that computation & communication complexity of private key, ciphertext, cryptographic computations and so on related to an entity in the hierarchy is independent to the hierarchy depth of the entity. Moreover, key escrow problem that any non-leaf entity in a hierarchical identity based cryptosystem can derive private keys for its descendants with use of its private key should be resolved, in order to prevent any entity from behaving on behalf of its descendants. In this paper, a new technique is introduced for composing a private key for each individual entity in HIBE system by differentiating between non-local identifiers and local identifiers of the identity of the entity. That we call Identifier Discrimination. With the technique, A selective identity secure HIBE system is constructed under Decisional Bilinear Diffie-Hellman (DBDH) assumption without using random oracles, where the private key and the ciphertext consist of constant number of group elements, and decryption requires only three bilinear map computations, regardless of the identity hierarchy depth. Moreover, in contrast to previous HIBE constructions, where private key for an entity can be derived by its ancestors with direct use of their private keys, key escrow problem inherent in identity based cryptosystems is resolved in our HIBE construction. Privilege of deriving private keys for an entity can be delegated to any of its ancestors through authorization by distributing specifically crafted values to the ancestor in our HIBE system, that we call Authorized Delegation.

General-Purpose Computing on Graphics Processing Units (GPGPU) allows to extend the scalability and performances of Multi-Agent Based Simulations (MABS). However, GPGPU requires the underlying program to be compliant with the specific architecture of GPU devices, which is very constraining. In this context, the GPU Environmental Delegation of Agent Perceptions principle has been proposed to ease the use of GPGPU for MABS. The idea is to identify in the model some computations which can be transformed into environmental dynamics and then translated into GPU modules. In this paper, we further trial this principle by testing its feasibility and genericness on a classic ABM, namely Reynolds's boids. The paper then shows that applying GPU delegation not only speeds up boids simulations but also produces an ABM which is easy to understand, thanks to a clear separation of concerns.

As the level of parallelism in manycore processors keeps increasing, providing efficient mechanisms for thread synchronization in concurrent programs is becoming a major concern. On cache-coherent shared-memory processors, synchronization efficiency is ultimately limited by the performance of the underlying cache coherence protocol. This article studies how hardware support for message passing can improve synchronization performance. Considering the ubiquitous problem of mutual exclusion, we devise novel algorithms for (i) classic locking, where application threads obtain exclusive access to a shared resource prior to executing their critical sections (CSes), and (ii) delegation, where CSes are executed by special threads. For classic locking, our HybLock algorithm uses a mix of shared memory and hardware message passing, which introduces the idea of hybrid synchronization algorithms. For delegation, we propose mp-server and HybComb : the former is a straightforward adaptation of the server approach to hardware message passing, whereas the latter is a novel hybrid combining algorithm. Evaluation on Tilera's TILE-Gx processor shows that HybLock outperforms the best known classic locks. Furthermore, mp-server can execute contended CSes with unprecedented throughput, as stalls related to cache coherence are removed from the critical path. HybComb can achieve comparable performance while avoiding the need to dedicate server cores. Consequently, our queue and stack implementations, based on the new synchronization algorithms, largely outperform their most efficient shared-memory-only counterparts.

IoT devices provide with real-time data to a rich ecosystems of services and applications that will be of uttermost importance for ubiquitous computing. The volume of data and the involved subscribe/notify signaling will likely become a challenge also for access and core netkworks. Designers may opt for microservice architectures and fog computing to address this challenge while offering the required flexibility for the main players of ubiquitous computing: nomadic users. Microservices require strong security support for Fog computing, to rely on nodes in the boundary of the network for secure data collection and processing. IoT low cost devices face outdated certificates and security support, due to the elapsed time from manufacture to deployment. In this paper we propose a solution based on microservice architectures and DNSSEC, DANE and chameleon signatures to overcome these difficulties. We will show how trap doors included in the certificates allow a secure and flexible delegation for off-loading data collection and processing to the fog. The main result is showing this requires minimal manufacture device configuration, thanks to DNSSEC support.

A lot of research has been devoted to the problem of defining and constructing signature schemes with various delegation properties. They mostly fit into two families. On the one hand, there are signature schemes that allow the delegation of signing rights, such as (hierarchical) identity-based signatures, attribute-based signatures, functional signatures, etc. On the other hand, there are malleable signature schemes, which make it possible to derive, from a signature on some message, new signatures on related messages without owning the secret key. This includes redactable signatures, set-homomorphic signatures, signatures on formulas of propositional logic, etc.

Dynamic Searchable Symmetric Encryption (DSSE) provides a simple and fast storage as well as retrieval method for encrypted profiles which stored in cloud. However, due to the nature of the symmetric encryption algorithm, it allows only one client to access the data. To make the scheme more practical, this paper propose a multi client dynamic symmetric searchable encryption scheme that could allow multi-client to search the privacy data with the delegation search token and dynamic delete expected files with delete token. Compared with similar works, our construction achieves a balance in network security and practical performance. We also demonstrate that the proposed scheme has same IND-CKA2 security property against adaptive adversary.

In Switzerland, overcrowding in tertiary emergency departments is a frequent problem, resulting in lengthy waiting times, lower satisfaction on the part of families and a risk for patient's safety. The setting up of a nurse consultation in a university paediatric emergency centre has helped to improve the quality of care in this context.

Linking pieces of design information for inspiration are an important part of the early phase of the design process. One key linking operation is assembling, wherein designers create new ideas by assembling partial or whole pieces of ideas together. How designers assemble the ideas reflect their design process. Hence, by developing a computational tool for assembling ideas, the underlying rules of design decision-making might be revealed. In this research, we employed a computational design method consisting of methodological mapping (jigsaw) and consequential analysis (Design Jigsaw system prototype) to create associations between varied types of information at different levels in the design information hierarchy. We then propose a system prototype called Design Jigsaw, based on the analysis of five representation schemes with network-like structures and sound delegation mechanisms. We also developed and explored the representation, components, and the control mechanisms involved in these components. The algorithm of the two main control strategies, grouping and matching/combining, is described in detail along with the procedural description of a jigsaw solving session. Furthermore, we conducted a design experiment to reify the process of the Design Jigsaw system prototype.

Introduction Congenital dislocation of the knee (CDK) is rare, and clinical semiology at birth is not always suitably analyzed. Existing classifications fail to guide treatment. The aim of the present study was to develop a CDK classification for the neonatal period. Hypothesis A classification based on neonatal severity of clinical signs is easy to implement on simple criteria. Material and methods Fifty-one CDKs (40 patients) seen neonatally were included. Three types could be distinguished in terms of reduction and stability: type I, easily reducible CDK, with reduction snap when the femoral condyles pass in flexion, remaining stable in flexion; type II, “recalcitrant” dislocation, reducible by posteroanterior “piston” but unstable, with iterative dislocation once posteroanterior pressure on the condyles is relaxed; and type III, irreducible. The number of anterior skin grooves, global range of motion, flexion deficit and reduction stability were noted for each type. Results Mean age at first consultation was 5.6 days (range: 0–30). CDK was type I, II and III in respectively 28, 16 and 7 cases. Number of skin grooves, flexion and baseline range of motion were greater in type I than types II and III. Conclusion The present neonatal clinical classification is original, logical and simple. It may be useful for prognosis and guiding treatment. Level of evidence IV, single-center retrospective series.

INTRODUCTION The U.K. library community has implemented collaborative strategies in key scholarly communication areas such as open access mandate compliance, and U.S. librarians could benefit from learning in greater detail about the practices and experiences of U.K. libraries with respect to how they have organized scholarly communication services. METHODS In order to better understand the scholarly communication activities in U.K. academic and research libraries, and how U.S. libraries could apply that experience in the context of their own priorities, an environmental scan via a survey of U.K. research libraries and in-person interviews were conducted. RESULTS U.K. libraries concentrate their scholarly communication services on supporting compliance with open access mandates and in the development of new services that reflect libraries’ shifting role from information consumer to information producer. DISCUSSION Due to the difference in the requirements of open access mandates in the U.K. as compared to the U.S., scholarly communication services in the U.K. are more focused on supporting compliance efforts. U.S. libraries engage more actively in providing copyright education and consultation than U.K. libraries. Both U.K. and U.S. libraries have developed new services in the areas of research data management and library publishing. CONCLUSION There are three primary takeaways from the experience of U.K. scholarly communication practitioners for U.S. librarians: increase collaboration with offices of research, reconsider current organization and delegation of scholarly communication services, and increase involvement in legislative and policy-making activity in the U.S. with respect to access to research.

International audience; Multi-Agent Based Simulation (MABS) is used to study complex systems in many research domains. As the number of modeled agents is constantly growing, using General-Purpose Computing on Graphics Units (GPGPU) appears to be very promising as it allows to use the massively parallel architecture of the GPU (Graphics Processing Unit) to do High Performance Computing (HPC). However, this technology relies on a highly specialized architecture, implying a very specific programming approach. So, to benefit from GPU power, a MABS model need to be adapted to the GPU programming paradigm.Contrary to some recent research works that propose to hide GPU programming to ease the use of GPGPU, we present in this paper a methodology for modeling and implementing MABS using GPU programming. The idea is to be able to consider any kind of MABS rather than addressing a limited number of cases. This methodology defines the iterative process to be followed to transform and adapt a model so that it takes advantage of the GPU power without hiding the underlying technology. We experiment this methodology on two MABS models to test its feasibility and highlight the advantages and limits of this approach.

In the roadmap for the implementation of ubiquitous computing, ubiquitous sensing and actuation is a milestone still to be reached. It refers to providing sensing and actuation facilities anytime and everywhere. This does not just imply to interconnect sensors and actuators through the Internet, but also and mainly to provide this facilities. IoT-Cloud computing paradigms such as the sensing and actuation as a service one could be a proper way to address this problem. In past work we developed an SAaaS framework extending OpenStack with specific functionalities for resource constrained nodes, Stack4Things. In this paper we focus on access control, authorization and delegation mechanisms which are basic mechanisms for the implementation of the UbSA vision. Thus starting from Stack4Things, we describe how we adapted and extended mechanisms provided by OpenStack, with specific regard to Keystone, with new functionalities for delegation and access control. A use case in the smart city scenario of #SmartME describes the proposed solution in practice.

Attrapadung (Eurocrypt 2014) proposed a generic framework called pair encoding to simplify the design and proof of security of CPA-secure predicate encryption (PE) in composite order groups. Later Attrapadung (Asiacrypt 2016) extended this idea in prime order groups. Yamada et al. (PKC 2011, PKC 2012) and Nandi et al. (ePrint Archive: 2015/457, AAECC 2017) proposed generic conversion frameworks to achieve CCA-secure PE from CPA-secure PE provided the encryption schemes have properties like delegation or verifiability. The delegation property is harder to achieve and verifiability based conversion degrades the decryption performance due to a large number of additional pairing evaluations. Blomer et al. (CT-RSA 2016) proposed a direct fully CCA-secure predicate encryption in composite order groups but it was less efficient as it needed a large number of pairing evaluations to check ciphertext consistency. As an alternative, Nandi et al. (ePrint Archive: 2015/955) proposed a direct conversion technique in composite order groups. We extend the direct conversion technique of Nandi et al. in the prime order groups on the CPA-secure PE construction by Attrapadung (Asiacrypt 2016) and prove our scheme to be CCA-secure in a quite different manner. Our first direct CCA-secure predicate encryption scheme requires exactly one additional ciphertext component and three additional units of pairing evaluation during decryption. The second construction requires exactly three additional ciphertext components but needs only one additional unit pairing evaluation during decryption. This is a significant improvement over conventional approach for CPA-to-CCA conversion in prime order groups.

Motivated by the unprecedented penetration of mobile communications technology, this work carefully brings into perspective the challenges related to heterogeneous communications and offloaded computation operating in cases of fault-tolerant computation, computing, and caching. We specifically focus on the emerging augmented reality applications that require reliable delegation of the computing and caching functionality to proximate resource-rich devices. The corresponding mathematical model proposed in this work becomes of value to assess system-level reliability in cases where one or more nearby collaborating nodes become temporarily unavailable. Our produced analytical and simulation results corroborate the asymptotic insensitivity of the stationary reliability of the system in question (under the "fast" recovery of its elements) to the type of the "repair" time distribution, thus supporting the fault-tolerant system operation. publishedVersion