Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Nicolae Paladi is active.

Publication


Featured researches published by Nicolae Paladi.


ieee international conference on cloud computing technology and science | 2017

Providing User Security Guarantees in Public Infrastructure Clouds

Nicolae Paladi; Christian Gehrmann; Antonis Michalas

The infrastructure cloud (IaaS) service model offers improved resource flexibility and availability, where tenants – insulated from the minutiae of hardware maintenance – rent computing resources to deploy and operate complex systems. Large-scale services running on IaaS platforms demonstrate the viability of this model; nevertheless, many organizations operating on sensitive data avoid migrating operations to IaaS platforms due to security concerns. In this paper, we describe a framework for data and operation security in IaaS, consisting of protocols for a trusted launch of virtual machines and domain-based storage protection. We continue with an extensive theoretical analysis with proofs about protocol resistance against attacks in the defined threat model. The protocols allow trust to be established by remotely attesting host platform configuration prior to launching guest virtual machines and ensure confidentiality of data in remote storage, with encryption keys maintained outside of the IaaS domain. Presented experimental results demonstrate the validity and efficiency of the proposed protocols. The framework prototype was implemented on a test bed operating a public electronic health record system, showing that the proposed protocols can be integrated into existing cloud environments.


Vitae-revista De La Facultad De Quimica Farmaceutica | 2014

“One of our hosts in another country”: Challenges of data geolocation in cloud storage

Nicolae Paladi; Antonis Michalas

Physical location of data in cloud storage is an increasingly urgent problem. In a short time, it has evolved from the concern of a few regulated businesses to an important consideration for many cloud storage users. One of the characteristics of cloud storage is fluid transfer of data both within and among the data centres of a cloud provider. However, this has weakened the guarantees with respect to control over data replicas, protection of data in transit and physical location of data. This paper addresses the lack of reliable solutions for data placement control in cloud storage systems. We analyse the currently available solutions and identify their shortcomings. Furthermore, we describe a high-level architecture for a trusted, geolocation-based mechanism for data placement control in distributed cloud storage systems, which are the basis of an on-going work to define the detailed protocol and a prototype of such a solution. This mechanism aims to provide granular control over the capabilities of tenants to access data placed on geographically dispersed storage units comprising the cloud storage.


international conference on information security and cryptology | 2012

Trusted launch of virtual machine instances in public iaas environments

Nicolae Paladi; Christian Gehrmann; Mudassar Aslam; Fredric Morenius

Cloud computing and Infrastructure-as-a-Service (IaaS) are emerging and promising technologies, however their adoption is hampered by data security concerns. At the same time, Trusted Computing (TC) is experiencing an increasing interest as a security mechanism for IaaS. In this paper we present a protocol to ensure the launch of a virtual machine (VM) instance on a trusted remote compute host. Relying on Trusted Platform Module operations such as binding and sealing to provide integrity guarantees for clients that require a trusted VM launch, we have designed a trusted launch protocol for VM instances in public IaaS environments. We also present a proof-of-concept implementation of the protocol based on OpenStack, an open-source IaaS platform. The results provide a basis for the use of TC mechanisms within IaaS platforms and pave the way for a wider applicability of TC to IaaS security.


international workshop on security | 2014

Domain based storage protection with secure access control for the cloud

Nicolae Paladi; Antonis Michalas; Christian Gehrmann

Cloud computing has evolved from a promising concept to one of the fastest growing segments of the IT industry. However, many businesses and individuals continue to view cloud computing as a technology that risks exposing their data to unauthorized users. We introduce a data confidentiality and integrity protection mechanism for Infrastructure-as-a-Service (IaaS) clouds, which relies on trusted computing principles to provide transparent storage isolation between IaaS clients. We also address the absence of reliable data sharing mechanisms, by providing an XML-based language framework which enables clients of IaaS clouds to securely share data and clearly define access rights granted to peers. The proposed improvements have been prototyped as a code extension for a popular cloud platform.


international conference on e-health networking, applications and services | 2014

Security aspects of e-Health systems migration to the cloud

Antonis Michalas; Nicolae Paladi; Christian Gehrmann

As adoption of e-health solutions advances, new computing paradigms - such as cloud computing - bring the potential to improve efficiency in managing medical health records and help reduce costs. However, these opportunities introduce new security risks which can not be ignored. Based on our experience with deploying part of the Swedish electronic health records management system in an infrastructure cloud, we make an overview of major requirements that must be considered when migrating e-health systems to the cloud. Furthermore, we describe in-depth a new attack vector inherent to cloud deployments and present a novel data confidentiality and integrity protection mechanism for infrastructure clouds. This contribution aims to encourage exchange of best practices and lessons learned in migrating public e-health systems to the cloud.


trust security and privacy in computing and communications | 2014

Trusted Geolocation-Aware Data Placement in Infrastructure Clouds

Nicolae Paladi; Mudassar Aslam; Christian Gehrmann

Data geolocation in the cloud is becoming an increasingly pressing problem, aggravated by incompatible legislation in different jurisdictions and compliance requirements of data owners. In this work we present a mechanism allowing cloud users to control the geographical location of their data, stored or processed in plaintext on the premises of Infrastructure-as-a Service cloud providers. We use trusted computing principles and remote attestation to establish platform state. We enable cloud users to confine plaintext data exclusively to the jurisdictions they specify, by sealing decryption keys used to obtain plaintext data to the combination of cloud host geolocation and platform state. We provide a detailed description of the implementation as well as performance measurements on an open source cloud infrastructure platform using commodity hardware.


international conference on security and privacy in communication systems | 2016

TruSDN : Bootstrapping trust in cloud network infrastructure

Nicolae Paladi; Christian Gehrmann

Software-Defined Networking (SDN) is a novel architectural model for cloud network infrastructure, improving resource utilization, scalability and administration. SDN deployments increasingly rely on virtual switches executing on commodity operating systems with large code bases, which are prime targets for adversaries attacking the network infrastructure. We describe and implement \( {\textsf{TruSDN}} \), a framework for bootstrapping trust in SDN infrastructure using Intel Software Guard Extensions (SGX), allowing to securely deploy SDN components and protect communication between network endpoints. We introduce ephemeral flow-specific pre-shared keys and propose a novel defense against cuckoo attacks on SGX enclaves. \( {\textsf{TruSDN}} \) is secure under a powerful adversary model, with a minor performance overhead.


nordic conference on secure it systems | 2013

Domain-Based Storage Protection DBSP in Public Infrastructure Clouds

Nicolae Paladi; Christian Gehrmann; Fredric Morenius

Confidentiality and integrity of data in Infrastructure-as-a-Service IaaS environments increase in relevance as adoption of IaaS advances towards maturity. While current solutions assume a high degree of trust in IaaS provider staff and infrastructure management processes, earlier incidents have demonstrated that neither are impeccable. In this paper we introduce Domain-Based Storage Protection DBSP a data confidentiality and integrity protection mechanism for IaaS environments, which relies on trusted computing principles to provide transparent storage isolation between IaaS clients. We describe the building blocks of this mechanism and provide a set of detailed protocols for generation and handling of keys for confidentiality and integrity protection of data stored by guest VM instances. The protocols assume an untrusted IaaS provider and aim to prevent both malicious and accidental faulty configurations that could lead to breach of data confidentiality and integrity in IaaS deployments.


Computer Science Review | 2017

A survey on design and implementation of protected searchable data in the cloud

Rafael Dowsley; Antonis Michalas; Matthias Nagel; Nicolae Paladi

While cloud computing has exploded in popularity in recent years thanks to the potential efficiency and cost savings of outsourcing the storage and management of data and applications, a number of vulnerabilities that led to multiple attacks have deterred many potential users. As a result, experts in the field argued that new mechanisms are needed in order to create trusted and secure cloud services. Such mechanisms would eradicate the suspicion of users towards cloud computing by providing the necessary security guarantees. Searchable Encryption is among the most promising solutions—one that has the potential to help offer truly secure and privacy-preserving cloud services. We start this paper by surveying the most important searchable encryption schemes and their relevance to cloud computing. In light of this analysis we demonstrate the inefficiencies of the existing schemes and expand our analysis by discussing certain confidentiality and privacy issues. Further, we examine how to integrate such a scheme with a popular cloud platform. Finally, we have chosen – based on the findings of our analysis – an existing scheme and implemented it to review its practical maturity for deployment in real systems. The survey of the field, together with the analysis and with the extensive experimental results provides a comprehensive review of the theoretical and practical aspects of searchable encryption.


Computers & Security | 2019

SDN Access Control for the Masses

Nicolae Paladi; Christian Gehrmann

The evolution of Software-Defined Networking (SDN) has so far been predominantly geared towards defining and refining the abstractions on the forwarding and control planes. However, despite a maturing south-bound interface and a range of proposed network operating systems, the network management application layer is yet to be specified and standardized. It has currently poorly defined access control mechanisms that could be exposed to network applications. Available mechanisms allow only rudimentary control and lack procedures to partition resource access across multiple dimensions. We address this by extending the SDN north-bound interface to provide control over shared resources to key stakeholders of network infrastructure: network providers, operators and application developers. We introduce a taxonomy of SDN access models, describe a comprehensive design for SDN access control and implement the proposed solution as an extension of the ONOS network controller intent framework.

Collaboration


Dive into the Nicolae Paladi's collaboration.

Top Co-Authors

Avatar

Christian Gehrmann

Swedish Institute of Computer Science

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Mudassar Aslam

Swedish Institute of Computer Science

View shared research outputs
Top Co-Authors

Avatar

Christian Gehrmann

Swedish Institute of Computer Science

View shared research outputs
Top Co-Authors

Avatar

Matthias Nagel

Karlsruhe Institute of Technology

View shared research outputs
Top Co-Authors

Avatar

Rafael Dowsley

Karlsruhe Institute of Technology

View shared research outputs
Top Co-Authors

Avatar

Hai-Van Dang

University of Westminster

View shared research outputs
Researchain Logo
Decentralizing Knowledge