Privilege Management Research Articles

모바일 클라우드 환경에서 안전한 프록시 재암호화 기반의 데이터 관리 방식

최근 모바일 클라우드 환경에서 공유되는 데이터의 기밀성과 유연성있는 접근제어를 보장하기 위해서 KP-ABE(Key Policy-Attribute Based Encryption)와 PRE(Proxy Re-Encryption)를 활용한 시스템 모델이 제안되었다. 그러나 기존 방식은 철회된 사용자와 클라우드 서버간의 공모 공격으로 데이터 기밀성을 침해하게 된다. 이러한 문제를 해결하기 위해서 제안 방식은 클라우드 서버에 저장되는 데이터 파일(data file)을 분산 저장하여 데이터 기밀성을 보장하고 비밀분산(Secret Sharing)를 통해서 프록시 재암호화키에 대한 변조 공격을 방지한다. 그리고 제안방식을 의료 환경에 적용한 프로토콜 모델을 구성한다. To ensure data confidentiality and fine-grained access control in business environment, system model using KP-ABE(Key Policy-Attribute Based Encryption) and PRE(Proxy Re-Encryption) has been proposed recently. However, in previous study, data confidentiality has been effected by decryption right concentrated on cloud server. Also, Yu's work does not consider a access privilege management, so existing work become dangerous to collusion attack between malicious user and cloud server. To resolve this problem, we propose secure system model against collusion attack through dividing data file into header which is sent to privilege manager group and body which is sent to cloud server and prevent modification attack for proxy re-encryption key using d Secret Sharing, We construct protocol model in medical environment.

Unified Authentication Scheme Based on IBE in Trusted Network

The existing unified authentication schemes are based on Public Key Infrastructure (PKI)/Privilege Management Infrastructure (PMI), WS-Security, Kerberos etc. But they can't support the developing Trusted Network Connect (TNC) environment. To solve the problem, a unified authentication scheme supporting multi-authentication modes based on Identity-Based Encryption (IBE) in trusted network named IEUAS is proposed. IEUAS authenticates the identity of a user by loading different authentication plugins to communicate with the related authentication servers. According to the legal identity of the user, a lightweight IBE system enforces four management mechanisms. They are the identity management, the key management, the application management and the domain management. Single Sign-On (SSO) and cross-domain SSO are implemented. The experiment results show that IEUAS can effectively solve the unified authentication problem in the TNC environment, and provide better security, efficiency and availability.

안전한 클라우드 비즈니스를 위한 접근권한 분산관리

최근 비즈니스 환경에서 공유되는 데이터의 기밀성과 유연성있는(fine-grained) 접근제어를 보장하기 위해서 KP-ABE(Key Policy-Attribute Based Encryption)와 PRE(Proxy Re-Encryption)를 활용한 시스템 모델이 제안되었다. 그러나 기존 방식은 클라우드 서버에 집중된 복호권한 때문에 데이터 기밀성을 침해하게 된다. 또한, 접근권한 관리에 대한 개념을 고려하지 않았으므로 악의적인 내부사용자의 공격에 취약하다. 이러한 문제를 해결하기 위해서 기존방식의 프로토콜 모델에서 권한 관리자 그룹을 두어 클라우드 서버에 저장되는 데이터 파일(data file)을 분산 저장하여 데이터 기밀성을 보장하고 AONT 기반의 XOR 임계치 비밀분산을 활용하여 접근권한 관리 모델을 구성하였다. 또한 XOR 쉐어를 활용하여 권한의 가중치를 부여할 수 있는 방법을 구체화했다. 4장에서 기존방식과 제안방식과의 비교 분석과 기능적 활용에 대해서 서술하여 제안방식의 차별화를 부각시켰다. To ensure data confidentiality and fine-grained access control in business environment, system model using KP-ABE(Key Policy-Attribute Based Encryption) and PRE(Proxy Re-Encryption) has been proposed recently. However, in previous study, data confidentiality has been effected by decryption right concentrated on cloud server. Also, Yu's work does not consider a access privilege management, so existing work become dangerous to collusion attack between malicious user and cloud server. To resolve this problem, we propose secure system model against collusion attack through dividing data file into header which is sent to privilege manager group and body which is sent to cloud server. And we construct the model of access privilege management using AONT based XOR threshold Secret Sharing, In addition, our scheme enable to grant weight for access privilege using XOR Share. In chapter 4, we differentiate existing scheme and proposed scheme.

Toward SVOPME, a Scalable Virtual Organization Privileges Management Environment

Grids enable uniform access to resources by implementing standard interfaces to resource gateways. In the Open Science Grid (OSG), privileges are granted on the basis of the user's membership to a Virtual Organization (VO). However, user privilege definitions and enforcements are administered separately by VOs and Grid sites. Such partitioning can potentially introduce inconsistent user privileges throughout the Grid and break the Grid paradigm of uniform access to resources. There is a need for an automated privilege management mechanism for a VO to codify privilege policies granted to its users, to propagate the policies to grid sites, to identity and suggest remedies for non-supported VO privileges at individual sites. The Scalable Virtual Organization Privileges Management Environment (SVOPME) addresses the challenge under the context of the Open Science Grid (OSG). The SVOPME provides tools for VOs to define and publish desired privileges. At a site, SVOPME tools help analyze access policies defined for VO users and verify policy consistency between VOs and sites, and suggest site configurations changes. This paper presents the designs and features of SVOPME tools and the lessons learned in applying SVOPME tools for OSG VOs and sites. Furthermore, we will outline future improvements to SVOPME tools to adapt to a range of different site configurations and new privilege policies.

Information Security Synthesis in Online Universities

Information assurance is at the core of every initiative that an organization executes. For online universities, a common and complex initiative is maintaining user lifecycle and providing seamless access using one identity in a large virtual infrastructure. To achieve information assurance the management of user privileges affected by events in the user's identity lifecycle needs to be the determining factor for access control. While the implementation of identity and access management systems makes this initiative feasible, it is the construction and maintenance of the infrastructure that makes it complex and challenging. The objective of this paper1 is to describe the complexities, propose a practical approach to building a foundation for consistent user experience and realizing security synthesis in online universities.

Privilege Management Infrastructure for Virtual Organizations in Healthcare Grids

This paper is focused on the management of virtual organizations (VO) inside healthcare environments where grid technology is used as middleware for a healthcare services-oriented architecture (HSOA). Some of the main tasks considered for the provision of an efficient VO management are management of users, assignation of roles to users, assignation of privileges to roles, and definition of resources access policies. These tasks are extremely close to privilege management infrastructures (PMI), so we face VO management services as part of the PMI supporting access control to healthcare resources inside the HSOA. In order to achieve a completely open and interoperable PMI, we review and apply standards of security and architectural design. Moreover, semantic technologies are introduced in decision points for access control allowing the management of a high degree of descriptors by means of ontologies and infer the decision making through rules and reasoners.

A web-based medical safety reporting system for a large multicenter clinical trial: The ALIAS experience

An electronic safety reporting (ESR) module was developed and integrated into a home-grown web-based clinical trial management system (CTMS) to enhance the efficiency, completeness and consistency of reporting and reviewing serious adverse events, monitoring safety, and submitting safety reports to regulatory authorities for a large multicenter clinical trial. The architecture of this integrated module provided many advantages. First, the ESR module was developed based on a comprehensive procedure which incorporated both computer logic processing steps and human intervention steps in order to deal with the complex and unexpected situations where pre-programmed computer logic may fail. Second, safety and efficacy data were managed within the same relational database. Relevant data captured on efficacy case report forms, such as demographics, medical history, lab data and concomitant medications, were directly retrievable for MedWatch report composition without requiring redundant data entry. Finally, the ESR module shared the same generic user interfaces and data processing functions with other modules in the CTMS. These generic components include data editing, data retrieving, data reporting, dictionary-based automatic and interactive coding, event-driven and calendar-driven automatic email notifications, and user privilege management. This integrated ESR module was implemented in the Albumin in Acute Stroke (ALIAS) Trial—Part 1. A total of 397 serious adverse event reports were processed and 33 FDA MedWatch reports, 28 initial reports, and 5 follow-up reports were submitted to FDA and Health Canada using this system. Experiences and lessons learned from the development and implementation of this system are presented in this paper.

SVOPME: A Scalable Virtual Organization Privileges Management Environment

Grids enable uniform access to resources by implementing standard interfaces to resource gateways. In the Open Science Grid (OSG), privileges are granted on the basis of the user's membership to a Virtual Organization (VO). However, Grid sites are solely responsible to determine and control access privileges to resources using users' identity and personal attributes, which are available through Grid credentials. While this guarantees full control on access rights to the sites, it makes VO privileges heterogeneous throughout the Grid and hardly fits with the Grid paradigm of uniform access to resources. To address these challenges, we are developing the Scalable Virtual Organization Privileges Management Environment (SVOPME), which provides tools for VOs to define and publish desired privileges and assists sites to provide the appropriate access policies. Moreover, SVOPME provides tools for Grid sites to analyze site access policies for various resources, verify compliance with preferred VO policies, and generate directives for site administrators on how the local access policies can be amended to achieve such compliance without taking control of local configurations away from site administrators. This paper discusses what access policies are of interest to the OSG community and how SVOPME implements privilege management for OSG.

Pervasive authentication and authorization infrastructures for mobile users

Network and device heterogeneity, nomadic mobility, intermittent connectivity and, more generally, extremely dynamic operating conditions, are major challenges in the design of security infrastructures for pervasive computing. Yet, in a ubiquitous computing environment, limitations of traditional solutions for authentication and authorization can be overcome with a pervasive public key infrastructure (pervasive-PKI). This choice allows the validation of credentials of users roaming between heterogeneous networks, even when global connectivity is lost and some services are temporarily unreachable. Proof-of-concept implementations and testbed validation results demonstrate that strong security can be achieved for users and applications through the combination of traditional PKI services with a number of enhancements like: (i) dynamic and collaborative trust model, (ii) use of attribute certificates for privilege management, and (iii) modular architecture enabling nomadic mobility and enhanced with reconfiguration capabilities.

A secure collaborative web-based environment for virtual organisations

The concept of the Virtual Organisation (VO) is a natural outcome of network evolution and the growth of collaborative work tools. In the projects Value Improvement thought a Virtual Aeronautical Collaborative Enterprise (VIVACE) and Transglobal Secure Collaboration Program (TSCP), we studied the different issues when setting VOs up. In this paper, we expose the requirements and characteristics of VOs through a use case where the partners produce a technical aeronautic specification, which was proposed by those consortiums. Then, we present a secured collaborative environment that we have deployed to deal with VO security constraints. It combines attribute-based access control models, privileges management infrastructure and identity federation to make VOs more dynamic.

A Semantic Cache Framework for Secure XML Queries

Secure XML query answering to protect data privacy and semantic cache to speed up XML query answering are two hot spots in current research areas of XML database systems. While both issues are explored respectively in depth, they have not been studied together, that is, the problem of semantic cache for secure XML query answering has not been addressed yet. In this paper, we present an interesting joint of these two aspects and propose an efficient framework of semantic cache for secure XML query answering, which can improve the performance of XML database systems under secure circumstances. Our framework combines access control, user privilege management over XML data and the state of-the-art semantic XML query cache techniques, to ensure that data are presented only to authorized users in an efficient way. To the best of our knowledge, the approach we propose here is among the first beneficial efforts in a novel perspective of combining caching and security for XML database to improve system performance. The efficiency of our framework is verified by comprehensive experiments.

Enabling Attribute Delegation in Ubiquitous Environments

When delegation is implemented using the attribute certificates in a Privilege Management Infrastructure (PMI), it is possible to reach a considerable level of distributed functionality. However, the approach is not flexible enough for the requirements of ubiquitous environments. The PMI can become a too complex solution for devices such as smartphones and PDAs, where resources are limited. In this work we present an approach to solve the previous limitations by defining a second class of attributes, called domain attributes, which are managed directly by users and are not right under the scope of the PMI, thus providing a light solution for constrained devices. However, we relate the two classes of attributes are related by defining a simple ontology. While domain attribute credentials are defined using SAML notation, global attributes are defined using X.509 certificates. For this reason, we additionally introduce XSAML so that both kinds of credentials are integrated. We also introduce the concept of Attribute Federation which is responsible for supporting domain attributes and the corresponding ontology.

Manageable fine-grained information flow

The continuing frequency and seriousness of security incidents underline the critical importance of application security. Decentralized information flow control (DIFC), a promising tool for improving application security, gives application developers fine-grained control over security policy and privilege management. DIFC developers can partition much application functionality into untrusted components bound by a kernel- or language-enforced security policy. Unless a (usually smaller and less exposed) trusted component is exploited, the effects of an application compromise are contained by the policy. Although system-based DIFC can simultaneously achieve high performance and effective isolation, it offers a challenging programming model. Fine-grained policy specifications are spread over several application pieces. Common programming errors may be indistinguishable from policy exploit attempts, the system cannot expose developers to information about these errors, complicating debugging. Static checking (as in language based systems) and new system primitives can reduce these problems, but for dynamic applications like web servers, they do not eliminate them. In this paper we propose subsystems that make decentralized information flow more manageable. First, a policy description language specifies an application-wide security policy in one localized place; communication restrictions are compiled into lower-level labels. Second, information flow-safe debugging mechanisms let developers debug DIFC applications without violating security policies. Although these mechanisms are preliminary, we demonstrate their effectiveness using applications similar to those developed for Asbestos and other DIFC systems.

Quality labels for e-health

A drug e-prescription demonstrator was created in compliance with existing legislation as well as security and privacy standards. A professional ID-card was built on a high security chip (ISTEC E4 High; EAL-5) with a Hash hardware accelerator for a digital signature placed in a single chip USB token. Commercial software products as well as development kits of the new hardware designed in the project were used to build an authentication, authorisation and electronic signature demonstrator. The degree of legal compliance was evaluated. The tested novel single chip USB token was highly efficient but limited by its 1.1 interface speed (12 Mbit/s). The chip, initialised with a banking-mask, inefficiently managed space for the health-care chain of trust. The public key and privilege management infrastructure was not able to handle health-care attributes in the appropriate extensions. Templates for role-rule privileges were not available and healthcare standards for security and privacy were not found in commercial products. The paper points out the urgent need for an e-health conformance label as well as a quality label for liability and confidence to gain users' trust.

Secure content access and replication in pure P2P networks

Despite the advantages offered by pure Peer-to-Peer (P2P) networks (e.g. robustness and fault tolerance), a crucial requirement is to guarantee basic security properties, such as content authenticity and integrity, as well as to enforce appropriate access control policies. These mechanisms would pave the way for new models in which content providers can exert some control over the replication and file sharing process. However, the extremely decentralized nature of these environments makes impossible to apply classic solutions that rely on some kind of fixed infrastructure, typically in the form of on-line trusted third parties (TTP). In this paper, we introduce a suite of protocols for content authentication and access control in pure P2P networks based on attribute certificates that does not rely on the existence of a public key infrastructure (PKI), privilege management infrastructure (PMI), or any other form of centralized authority. We provide an analysis concerning the efficiency (computational effort and communication overhead) and the security of our proposal.

Enter the working forest: Discourse analysis in the Northern Forest

In 1988, four states in the northeastern USA commissioned a study to address land use changes in the Northern Forest, 26 million acres of temperate and boreal forest extending from Maine to eastern New York State. Against a backdrop of economic destabilization and concerns regarding social and ecological implications of a real estate boom, the sustained deliberative dialogue catalyzed by this study has come to rely heavily on the ambiguous concept of “working forest.” To clarify political and environmental dynamics in the region, we analyzed how people respond to and seek to capitalize on the interpretive flexibility of the term working forest. We combine an analysis of socio-political discourses of working forest based on a structured literature review with an assessment of local peoples’ definitions of working forest based on a survey conducted in a pair of contrasting New York State communities. The first study site represents an amenity-oriented community ( i. e. a place where the forest supports a service economy including recreation and tourism) and the other study site represents a timber-dependent community. By linking data from community-level analysis to data derived from a general analysis of forest politics, we seek to develop a more robust perspective. By comparing discourses across differently structured communities, we investigate how local forest politics are mediated by local economic development processes. Our study empirically illustrates contested and geographically uneven processes of social construction of environment and rural development in a region confronting pressures of globalization. Results indicate that timber harvesting is a heavily privileged management objective, as a logic of ‘ the forest that pays is the forest that stays’ dominates. Environmental politics in the region, and perhaps more generally, increasingly conforms to a form of pragmatism in which economic opportunities structure conservation planning and investment.

An integrated approach to federated identity and privilege management in open systems

Online partnerships depend on federations of not only user identities but also of user entitlements across organizational boundaries.

On the deployment of a real scalable delegation service

This paper explains the evolution of the concept of delegation since its first references in the context of distributed authorization to the actual use as a fundamental part of a privilege management architecture. The work reviews some of the earliest contributions that pointed out the relevance of delegation when dealing with distributed authorization, in particular we comment on PolicyMaker and KeyNote, and also on SDSI/SPKI. Then, we elaborate on Federation as a particular case of delegation, and remark the importance given to Federation by the industry. Finally, the paper discusses about Privilege Management Infrastructures, introducing a new mechanism to extend their functionality using advanced delegation services.

A cache considering role-based access control and trust in privilege management infrastructure

PMI (privilege management infrastructure) is used to perform access control to resource in an E-commerce or E-government system. With the ever-increasing need for secure transaction, the need for systems that offer a wide variety of QoS (quality-of-service) features is also growing. In order to improve the QoS of PMI system, a cache based on RBAC (Role-based Access Control) and trust is proposed. Our system is realized based on Web service. How to design the cache based on RBAC and trust in the access control model is described in detail. The algorithm to query role permission in cache and to add records in cache is dealt with. The policy to update cache is introduced also.

Anonymous attribute certificates based on traceable signatures

PurposeTo provide a cryptographic protocol for anonymously accessing services offered on the web. Such anonymous accesses can be disclosed or traced under certain conditions.Design/methodology/approachThe “traceable signature” scheme was used in conjunction with the “privilege management infrastructure”.FindingsThe cryptographic primitive provides a suitable tool for anonymous and unlinkable access to web resources based on the privileges that users hold. Moreover, the scheme allows for anonymity revocation and tracing of unlinkable accesses.Research limitations/implicationsThe power of the attribute authority should be divided into several entities, one of them being a trusted third party, to avoid illicit disclosing of information.Practical implicationsNew systems with support for anonymous access to web resources can be developed.Originality/valueThis paper adds the unlinkability property to anonymous accesses together with a tracing facility to existing proposals.