publications-hd-2010-2019.bib

@inproceedings{bernard2012cross,
  title = {Cross-domain vulnerabilities over social networks},
  author = {Bernard, Catherine and Debar, Herv{\'e} and
                  Benayoune, Salim},
  booktitle = {Proceedings of the 4th International Conference on
                  Computational Aspects of Social Networks (CASoN'12)},
  pages = {8--13},
  year = 2012,
  location = {Sao Carlos, Brazil},
  url = {http://hal.archives-ouvertes.fr/hal-00813344},
  doi = {10.1109/CASoN.2012.6412370},
  keywords = {Internet, computer crime, social networking
                  (online), unsolicited e-mail, video signal
                  processing, video streaming, Adobe Flash, Facebook,
                  Internet, Twitter, YouTube, cross-domain
                  vulnerabilities, phishing vectors, social networks,
                  spam, video sharing site, video streaming
                  application, video traffic, Browsers, security,
                  servers, streaming media, cross-domain attack, Flash
                  security, social network security},
  abstract = {Recent years have seen a tremendous growth of social
                  networks such as Facebook and Twitter. At the same
                  time, the share of video traffic in the Internet has
                  also significantly increased, and the two functions
                  are getting closer to one another. YouTube, the most
                  famous video sharing site, allows people to comment
                  on videos with other people while Facebook and
                  Twitter are important vectors into sharing
                  videos. Both video channels and social networks are
                  increasingly vulnerable attack targets. For example,
                  social networks are also considerable spam and
                  phishing vectors, and Adobe Flash as the premier
                  video streaming application is associated with
                  numerous software vulnerabilities. This is a good
                  way for attackers to compromise sites with embedded
                  Flash objects. In this paper, we present the
                  technical background of the cross-domain mechanisms
                  and the security implications. Several recent
                  studies have demonstrated the weakness of the
                  cross-domain policy, leading to session hijacking or
                  the leakage of sensitive information. Current
                  solutions to detect these vulnerabilities use a
                  client-side approach. The purpose of our work is to
                  present a new approach based on network flows
                  analysis to detect malicious behavior.},
  month = {November},
  organization = {IEEE}
}
@inproceedings{carlinet2010caching,
  title = {Caching P2P Traffic: What are the Benefits for an
                  ISP?},
  author = {Carlinet, Yannick and Debar, Herv{\'e} and Gourhant,
                  Yvon and M{\'e}, Ludovic},
  booktitle = {Proceedings of the Ninth International Conference on
                  Networks (ICN'2010)},
  pages = {376--383},
  year = 2010,
  organization = {IEEE},
  month = {April},
  keywords = {cache storage, peer-to-peer computing,
                  telecommunication traffic, ISP, P2P overlay, P2P
                  traffic, cache performances, peer-to-peer traffic,
                  Bandwidth, Costs, IP networks, Large-scale systems,
                  Monitoring, Peer to peer computing, Performance
                  evaluation, Telecommunication traffic, Traffic
                  control, Cache, traffic modeling, traffic
                  monitoring},
  doi = {10.1109/ICN.2010.67},
  abstract = {Caching P2P content could be an effective way of
                  alleviating network usage, thereby reducing
                  operation costs for operators. However, cache
                  performances are affected by a lot of factors
                  related to the cache itself, but also to the
                  properties of the P2P overlay, the P2P contents, and
                  the cache deployment location. In order to evaluate
                  the potential usefulness of P2P caches, we have
                  setup a large-scale experiment for monitoring
                  traffic of a popular P2P application in the
                  operational network of France Telecom. After gaining
                  some insights on the characteristics of the P2P
                  traffic, we simulate a cache based on data contained
                  in our trace. We are then able to evaluate cache
                  performances in terms of the bandwidth that could
                  have been saved if a cache was really in the network
                  during our measurements. Additionally, the paper
                  studies the impact of various factors on
                  performance, such as cache properties and more
                  importantly the number of customers served by the
                  cache. The results show that the bandwidth gain can
                  reach 23\% of P2P traffic with a passive cache.}
}
@inproceedings{carlinet2010evaluation,
  title = {Evaluation of P4P Based on Real Traffic Measurement},
  author = {Carlinet, Yannick and Mé, Ludovic and Gourhant, Yvon
                  and Debar, Herv{\'e}},
  booktitle = {Proceedings of the Fifth International Conference on
                  Internet Monitoring and Protection (ICIMP 2010)},
  pages = {129--134},
  year = 2010,
  organization = {IEEE},
  url = {http://hal-supelec.archives-ouvertes.fr/hal-00534571},
  month = {May},
  keywords = {peer-to-peer computing, P2P traffic, P4P evaluation,
                  network infrastructure, peer-to-peer traffic, real
                  traffic measurement, system testing, P2P, P4P,
                  Peer-to-peer, traffic monitoring, traffic
                  optimization, transit/peering points},
  doi = {10.1109/ICIMP.2010.25},
  abstract = {Peer-To-Peer (P2P) traffic represents a significant
                  proportion of the traffic today. However, currently
                  widespread P2P systems take no account of the
                  underlying network infrastructure. But by doing so,
                  they would be able to perform a much more efficient
                  peer selection. The P4P approach aims at allowing
                  ISPs to cooperate with peers in order to improve
                  their peer selection in the overlay. The objectives
                  of this paper are to assess the benefits of P4P,
                  both for the P2P system and the ISP, thanks to an
                  experiment of a scale never achieved before, there
                  by complementing the results obtained in previous
                  work. The results show that P2P applications need
                  more information than just the Internet domain, in
                  order to improve their performance, and that the
                  inter-domain P2P traffic can be reduced by at least
                  72\%.}
}
@inproceedings{cuppens2010negotiation,
  title = {Negotiation of Prohibition: An Approach Based on
                  Policy Rewriting},
  author = {Cuppens, Nora and Cuppens, Fr{\'e}d{\'e}ric and
                  Haidar, D Abi and Debar, Herv{\'e}},
  pages = {173--187},
  year = 2008,
  isbn = {978-0-387-09698-8},
  booktitle = {Proceedings of the {IFIP TC11} 23rd International
                  Information Security Conference (SEC'08},
  volume = 278,
  series = {{IFIP} – The International Federation for
                  Information Processing},
  editor = {Jajodia, Sushil and Samarati, Pierangela and Cimato,
                  Stelvio},
  doi = {10.1007/978-0-387-09699-5_12},
  keywords = {security policies, OrBAC, ABAC, access control,
                  access control models, negotiation, policy
                  negotiation, access negotiation},
  abstract = {Traditionally, access control is enforced by
                  centralized stand-alone architectures. In this case,
                  the access controller knows all information
                  necessary to evaluate the access control policy. As
                  a consequence, when a subject sends a query to the
                  access controller, this access controller does not
                  need to interact with this subject to decide if this
                  query must be accepted or rejected. }
}
@inproceedings{dassouki2013tcp,
  title = {A TCP delay-based mechanism for detecting congestion
                  in the Internet},
  author = {Dassouki, Khaled and Debar, Herv{\'e} and Safa,
                  Haidar and Hijazi, Abbas},
  booktitle = {Proceedings of the Third International Conference on
                  Communications and Information Technology (ICCIT
                  2013)},
  pages = {141--145},
  year = 2013,
  organization = {IEEE},
  location = {Beirut, Lebanon},
  month = {June},
  doi = {10.1109/ICCITechnology.2013.6579538},
  url = {http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6579538&isnumber=6579508},
  keywords = {Internet, telecommunication links, transport
                  protocols, Internet congestion, TCP delay-based
                  mechanism, active queue management algorithms,
                  aggregation link, buffer statistics, Algorithm
                  design and analysis, Delays, Estimation, Information
                  technology, Monitoring, Active Queue Management,
                  Congestion Detection, TCP, throughput},
  abstract = {Internet congestion existing solutions such as
                  active queue management algorithms have many
                  shortcomings, mainly related to the detection
                  phase. These algorithms depend on routers' buffer
                  statistics to detect congestion and their
                  performance is highly affected by the environment
                  and the parameters that are used. In this paper we
                  are proposing a mechanism that is capable of
                  detecting congestions by monitoring passively an
                  aggregation link. The proposed mechanism does not
                  need parameterizations since all the used parameters
                  are deduced from public real internet traces using
                  statistical approaches and uses TCP delays as a
                  detection parameter. It is dynamic since the
                  detection is proportional to the severity of the
                  congestion. Experimental results have shown that the
                  proposed mechanism is able to detect congestion
                  rapidly and does not suffer from false alarms.}
}
@inproceedings{debar2010service,
  title = {Service dependencies in information systems
                  security},
  author = {Debar, Herv{\'e} and Kheir, Nizar and
                  Cuppens-Boulahia, Nora and Cuppens,
                  Fr{\'e}d{\'e}ric},
  booktitle = {Proceedings of the 5th International Conference on
                  Mathematical Methods, Models and Architectures for
                  Computer Network Security (MMM-ACNS'10)},
  pages = {1--20},
  year = 2010,
  isbn = {3-642-14705-4, 978-3-642-14705-0},
  location = {St. Petersburg, Russia},
  volume = 6258,
  series = {Lecture Notes in Computer Science},
  editor = {Kotenko, Igor and Skormin, Victor},
  doi = {10.1007/978-3-642-14706-7_1},
  numpages = 20,
  url = {http://dl.acm.org/citation.cfm?id=1885194.1885196},
  acmid = 1885196,
  publisher = {Springer-Verlag},
  address = {Berlin, Heidelberg},
  keywords = {intrusion detection, counter-measures, intrusion
                  response, service dependencies},
  abstract = {In the complex world of information services, we are
                  realizing that system dependencies upon one another
                  have not only operational implications but also
                  security implications. These security implications
                  are multifold. Beyond allowing an attacker to
                  propagate over an information system by leveraging
                  stepping stones vulnerabilities, it also allows a
                  defender to select the most interesting enforcement
                  points for its policies, overall reducing the cost
                  of managing the security of these complex
                  systems. In this paper, we present a dependency
                  model that has been designed for the purpose of
                  providing security operators with a quantitative
                  decision support system for deploying and managing
                  security policies.}
}
@inproceedings{granadillo2012combination,
  title = {Combination approach to select optimal
                  countermeasures based on the RORI index},
  author = {Granadillo, Gustavo Gonzalez and Jacob, Greagoire
                  and Debar, Herv{\'e} and Coppolino, Luigi},
  booktitle = {Proceedings of the Second International Conference
                  onInnovative Computing Technology (INTECH'2012)},
  pages = {38--45},
  year = 2012,
  month = {September},
  location = {Casablanca, Maroc},
  organization = {IEEE},
  doi = {10.1109/INTECH.2012.6457801},
  url = {http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6457801},
  keywords = {Internet, security of data, RORI index, appropriate
                  attack mitigation, combination approach, complex
                  attack effect mitigation, computer attacks,
                  cost-effective attack mitigation, cost-effectiveness
                  ratio maximization, critical infrastructure process
                  control, individual security solutions, optimal
                  countermeasure selection, return-on-response
                  investment index, Equations, Indexes, Integrated
                  circuits, Investments, Mathematical model, Process
                  control, Security},
  abstract = {As new and more sophisticated computer attacks
                  appear across the Internet, sometimes with unknown
                  dimensions and criticality, the implementation of
                  individual security solutions become less effective
                  and in some cases useless. Instead, a combined
                  approach is required to guarantee an appropriate and
                  cost-effective mitigation of such attacks. Most of
                  the current work suggests the deployment of multiple
                  countermeasures as a single treatment to mitigate
                  the effects of complex attacks. However, the
                  methodology to analyze and evaluate combined
                  solutions is either hardly explained or very
                  complicated to implement. This paper, therefore
                  proposes a simple and well-structured approach to
                  select the optimal combination of countermeasures by
                  maximizing the cost-effectiveness ratio of the
                  countermeasures, this ratio being measured by the
                  Return on Response Investment (RORI) index. A case
                  study is provided at the end of the document to show
                  the applicability of the model over a critical
                  infrastructure process control.}
}
@inproceedings{granadillo2012individual,
  title = {Individual countermeasure selection based on the
                  return on response investment index},
  author = {GRANADILLO, Gustavo Daniel GONZALEZ and DEBAR,
                  Herv{\'e} and Jacob, Gr{\'e}goire and Gaber,
                  Chrystel and Achemlal, Mohamed and others},
  booktitle = {Proceedings of the Sixth International Conference on
                  Mathematical Methods, Models, and Architectures for
                  Computer Network Security (MMM-ACNS'12) },
  pages = {156--170},
  year = 2012,
  month = {October},
  url = {http://link.springer.com/chapter/10.1007%2F978-3-642-33704-8_14},
  location = {St Petersburg, Russia},
  isbn = {978-3-642-33703-1},
  volume = 7531,
  series = {Lecture Notes in Computer Science},
  editor = {Kotenko, Igor and Skormin, Victor},
  doi = {10.1007/978-3-642-33704-8_14},
  publisher = {Springer Berlin Heidelberg},
  keywords = {intrusion response, SIEM},
  abstract = {As the number of attacks, and thus the number of
                  alerts received by Security Information and Event
                  Management Systems (SIEMs) increases, the need for
                  appropriate treatment of these alerts has become
                  essential. The new generation of SIEMs focuses on
                  the response ability to automate the process of
                  selecting and deploying countermeasures. However,
                  current response systems select and deploy security
                  measures without performing a comprehensive impact
                  analysis of attacks and response scenarios. This
                  paper addresses this limitation by proposing a model
                  for the automated selection of optimal security
                  countermeasures. In addition, the paper compares
                  previous mathematical models and studies their
                  limitations, which lead to the creation of a new
                  model that evaluates, ranks and selects optimal
                  countermeasures. The model relies on the
                  optimization of cost sensitive metrics based on the
                  Return On Response Investment (RORI) index. The
                  optimization compares the expected impact of the
                  attacks when doing nothing with the expected impact
                  after applying countermeasures. A case study of a
                  real infrastructure is deployed at the end of the
                  document to show the applicability of the model over
                  a Mobile Money Transfer Service.}
}
@incollection{granadillo2012ontology,
  title = {An ontology-based model for SIEM environments},
  author = {Granadillo, Gustavo Gonzalez and Mustapha, Yosra Ben
                  and Hachem, Nabil and Debar, Herv{\'e}},
  booktitle = {Global Security, Safety and Sustainability \&
                  e-Democracy},
  pages = {148--155},
  year = 2012,
  publisher = {Springer Berlin Heidelberg},
  isbn = {978-3-642-33447-4},
  volume = 99,
  series = {Lecture Notes of the Institute for Computer
                  Sciences, Social Informatics and Telecommunications
                  Engineering},
  editor = {Georgiadis, ChristosK. and Jahankhani, Hamid and
                  Pimenidis, Elias and Bashroush, Rabih and Al-Nemrat,
                  Ameer},
  doi = {10.1007/978-3-642-33448-1_21},
  url = {http://link.springer.com/chapter/10.1007%2F978-3-642-33448-1_21},
  keywords = {SIEM; Ontology; Data Model},
  abstract = {The management of security events, from the analysis
                  of attacks and risk to the selection of appropriate
                  countermeasures, has become a major concern for
                  security analysts and IT
                  administrators. Furthermore, network and system
                  devices are designed to be heterogeneous, with
                  different characteristics and functionalities that
                  increase the difficulty of these tasks. This paper
                  introduces an ontology-driven approach to address
                  the aforementioned problems. The proposed model
                  takes into account the two main aspects of this
                  field, the information that is manipulated by SIEM
                  environments and the operations that are applied to
                  this information, in order to reach the desired
                  goals. We present a case study on Botnets to
                  illustrate the utilization of our model.}
}
@article{granadillo2012ontology-swrl,
  title = {An ontology--driven approach to model SIEM
                  information and operations using the SWRL formalism},
  author = {Granadillo, Gustavo Gonzalez and Mustapha, Yosra Ben
                  and Hachem, Nabil and Debar, Herv{\'e}},
  journal = {International Journal of Electronic Security and
                  Digital Forensics},
  volume = 4,
  number = 2,
  pages = {104--123},
  year = 2012,
  publisher = {Inderscience},
  doi = {10.1504/IJESDF.2012.048412},
  url = {http://www.inderscience.com/info/inarticle.php?artid=48412},
  keywords = {security events, event management, security
                  information, SIEM, ontology, SWRL, semantics, logic
                  rules, data modelling, heterogeneity, reasoning,
                  risk assessment, countermeasures, botnets},
  abstract = {The management of security events, from the risk
                  analysis to the selection of appropriate
                  countermeasures, has become a major concern for
                  security analysts and IT
                  administrators. Furthermore, the fact that network
                  and system devices are heterogeneous, increases the
                  difficulty of these administrative tasks. This paper
                  introduces an ontology-driven approach to address
                  the aforementioned problems. The proposed model
                  takes into account two aspects: the information and
                  the operations that are manipulated by SIEM
                  environments in order to reach the desired
                  goals. The model uses ontologies to provide
                  simplicity on the description of concepts,
                  relationships and instances of the security
                  domain. The semantics web rule languages are used to
                  describe the logic rules needed to infer
                  relationships among individuals and classes. A case
                  study on Botnets is presented at the end of this
                  paper to illustrate a concrete utilisation of our
                  model.}
}
@article{granadillo2013rori,
  title = {RORI-based countermeasure selection using the OrBAC
                  formalism},
  author = {Granadillo, Gustavo Gonzalez and Belhaouane, Malek
                  and Debar, Herv{\'e} and Jacob, Gr{\'e}goire},
  journal = {International Journal of Information Security},
  publisher = {Springer Berlin Heidelberg},
  year = 2014,
  issn = {1615-5262},
  volume = 13,
  number = 1,
  doi = {10.1007/s10207-013-0207-8},
  url = {http://link.springer.com/article/10.1007%2Fs10207-013-0207-8},
  keywords = {Countermeasure selection, Impact analysis,
                  Combination approach, Risk mitigation, Surface
                  coverage, RORI index, OrBAC model},
  pages = {63-79},
  abstract = {Attacks against information systems have grown in
                  sophistication and complexity, making the detection
                  and reaction process a challenging task for security
                  administrators. In reaction to these attacks, the
                  definition of security policies is an effective way
                  to protect information systems from further damages,
                  but it requires a great expertise and knowledge. If
                  stronger security policies can constitute powerful
                  countermeasures, inappropriate policies, on the
                  other hand, may result in disastrous consequences
                  for the organization. The implementation of stronger
                  security policies requires in many cases the
                  evaluation and analysis of multiple
                  countermeasures. Current research promotes the
                  implementation of multiple countermeasures as a
                  strategy to react over complex attacks; however, the
                  methodology is either hardly explained or very
                  complicated to implement. This paper introduces a
                  well-structured approach to evaluate and select
                  optimal countermeasures based on the return on
                  response investment (RORI) index. An implementation
                  of a real case study is provided at the end of the
                  document to show the applicability of the model over
                  a mobile money transfer service. The service,
                  security policies and countermeasures are expressed
                  using the OrBAC formalism.}
}
@inproceedings{hachem2011botnets,
  title = {Botnets: Lifecycle and Taxonomy},
  author = {Hachem, Nabil and Ben Mustapha, Yosra and
                  Granadillo, Gustavo Gonzalez and Debar, Herv{\'e}},
  booktitle = {Network and Information Systems Security (SAR-SSI),
                  2011 Conference on},
  pages = {1--8},
  year = 2011,
  month = {May},
  location = {La Rochelle, France},
  organization = {IEEE},
  url = {http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=5931395},
  doi = {10.1109/SAR-SSI.2011.5931395},
  keywords = {Internet, computer crime, computer network security,
                  computer viruses, fraud, DDoS attack, Internet,
                  Zombies, agents, attack phase, attacker, botnet,
                  fraud, infected computer, large-scale coordinated
                  attack, life cycle, malware, phishing campaign,
                  resilience technique, spam, threat, Computers,
                  Internet, Malware, Protocols, Servers, Topology},
  abstract = {The new threat of the Internet, but little known to
                  the 'general public' is constituted by
                  botnets. Botnets are networks of infected computers,
                  which are headed by a pirate called also 'Attacker'
                  or 'Master'. The botnets are nowadays mainly
                  responsible for large-scale coordinated attacks. The
                  attacker can ask the infected computers called
                  'Agents' or 'Zombies' to perform all sorts of tasks
                  for him, like sending spam, performing DDoS attacks,
                  phishing campaigns, delivering malware, or leasing
                  or selling their botnets to other fraudsters
                  anywhere. In this paper we present a classification
                  that reflects the life cycle and current resilience
                  techniques of botnets, distinguishing the
                  propagation, the injection, the control and the
                  attack phases. Then we study the effectiveness of
                  the adopted taxonomy by applying it to existing
                  botnets to study their main characteristics. We
                  conclude by the upcoming steps in our research.}
}
@inproceedings{hachem2012hadega,
  title = {HADEGA: A novel MPLS-based mitigation solution to
                  handle network attacks},
  author = {Hachem, Nabil and Debar, Herv{\'e} and
                  Garcia-Alfaro, Joaquin},
  booktitle = {Proceedings of the IEEE 31st International
                  Performance Computing and Communications Conference
                  (IPCCC'2012)},
  location = {Austin, Texas},
  pages = {171--180},
  year = 2012,
  month = {December},
  organization = {IEEE},
  url = {http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6407750},
  doi = {10.1109/PCCC.2012.6407750},
  keywords = {telecommunication security, telecommunication
                  standards, HADEGA, MPLS standard, MPLS-based
                  mitigation solution, adaptive mitigation solution,
                  multiprotocol label switching, network attack
                  handling, network detection alerts, IP networks,
                  Multiprotocol label switching, Network topology,
                  Quality of service, Routing, Standards,
                  Multiprotocol Label Switching, Network Attack
                  Mitigation, Network Security, QoS},
  abstract = {We present HADEGA, a novel adaptive mitigation
                  solution to handle the impact of network attacks. By
                  extracting information from network detection
                  alerts, and build upon the Multiprotocol Label
                  Switching (MPLS) standard, the solution assigns
                  labels and quality of service treatments to
                  suspicious flows. As a result, those labeled flows
                  are controlled and properly handled inside the core
                  network of service providers. We conducted
                  simulations in order to evaluate the efficiency of
                  our approach. Results are presented.}
}
@inproceedings{hachem2013adaptive,
  title = {An Adaptive Mitigation Framework for Handling
                  Suspicious Network Flows via MPLS Policies},
  author = {Hachem, Nabil and Garcia-Alfaro, Joaquin and Debar,
                  Herv{\'e}},
  booktitle = {Secure IT Systems - Proceedings of the 18th Nordic
                  Conference (NordSec 2013)},
  location = {Ilulissat, Greenland},
  month = {October},
  pages = {297--312},
  year = 2013,
  publisher = {Springer Berlin Heidelberg},
  isbn = {978-3-642-41487-9},
  volume = 8208,
  series = {Lecture Notes in Computer Science},
  editor = {Riis Nielson, Hanne and Gollmann, Dieter},
  doi = {10.1007/978-3-642-41488-6_20},
  url = {http://link.springer.com/chapter/10.1007%2F978-3-642-41488-6_20},
  keywords = {Network Security, Policy Management, MPLS, OrBAC},
  abstract = {As network attacks become more complex, defence
                  strategies must provide means to handle more
                  flexible and dynamic requirements. The Multiprotocol
                  Label Switching (MPLS) standard is a promising
                  method to properly handle suspicious flows
                  participating in such network attacks. Tasks such as
                  alert data extraction, and MPLS routers
                  configuration present an entailment to activate the
                  defence process. This paper introduces a novel
                  framework to define, generate and implement
                  mitigation policies on MPLS routers. The activation
                  of such policies is triggered by the alerts and
                  expressed using a high level formalism. An
                  implementation of the approach is presented.}
}
@inproceedings{jacob2010formalization,
  title = {Formalization of viruses and malware through process
                  algebras},
  author = {Jacob, Gr{\'e}goire and Filiol, Eric and Debar,
                  Herv{\'e}},
  booktitle = {Proceedings of the International Conference on
                  Availability, Reliability, and Security (ARES'10)},
  pages = {597--602},
  year = 2010,
  month = {February},
  location = {Krakow, Poland},
  organization = {IEEE},
  keywords = {decidability, invasive software, process algebra,
                  Join-Calculus, Turing-equivalent formalisms,
                  abstract virology, detection undecidability, malware
                  formalization, process algebras, process-based
                  malware model, viral models, virus formalization,
                  Algebra, Availability, Calculus, Computer viruses,
                  Concurrent computing, Jacobian matrices, Protection,
                  Security, Steganography, detection, malware,
                  prevention},
  doi = {10.1109/ARES.2010.59},
  abstract = {Abstract virology has seen the apparition of
                  successive viral models, all based on
                  Turing-equivalent formalisms. Considering recent
                  malware, these are only partially covered because
                  functional formalisms do not support interactive
                  computations. This article provides a basis for a
                  unified malware model, founded on the
                  Join-Calculus. In terms of expressiveness, the
                  process-based model supports the fundamental notion
                  of self-replication but also interactions,
                  concurrency and non-termination to cover evolved
                  malware. In terms of protection, detection
                  undecidability and prevention by isolation still
                  hold. Additional results are established: calculus
                  fragments where detection is decidable, definition
                  of a non-infection property, potential solutions to
                  restrict propagation.}
}
@inproceedings{kheir2010ex,
  title = {Ex-SDF: An Extended Service Dependency Framework for
                  Intrusion Impact Assessment},
  author = {Kheir, Nizar and Cuppens-Boulahia, Nora and Cuppens,
                  Fr{\'e}d{\'e}ric and Debar, Herv{\'e}},
  journal = {Security and Privacy--Silver Linings in the Cloud},
  pages = {148--160},
  year = 2010,
  isbn = {978-3-642-15256-6},
  booktitle = {Proceedings of the 25th IFIP TC-11 International
                  Information Security Conference (SEC'2010)},
  location = {Brisbane, Australia},
  month = {September},
  volume = 330,
  series = {IFIP Advances in Information and Communication
                  Technology},
  editor = {Rannenberg, Kai and Varadharajan, Vijay and Weber,
                  Christian},
  doi = {10.1007/978-3-642-15257-3_14},
  url = {http://link.springer.com/chapter/10.1007%2F978-3-642-15257-3_14},
  publisher = {Springer Berlin Heidelberg},
  keyword = {intrusion response, service dependencies},
  abstract = {Information systems are increasingly dependent on
                  highly distributed architectures that include
                  multiple dependencies. Even basic attacks like
                  script-kiddies have drastic effects on target
                  systems as they easily spread through existing
                  dependencies. Unless intrusion effects are
                  accurately assessed, response systems will still be
                  blinded when selecting optimal responses. In fact,
                  using only response costs as a basis to select
                  responses is still meaningless if not compared to
                  intrusion costs. While conventional responses
                  provoke mostly availability impacts, intrusions
                  affect confidentiality, integrity and availability.
                  This paper develops an approach to assess intrusion
                  impacts on IT systems. It uses service dependencies
                  as frames for propagating impacts. It goes beyond
                  existing methods which mostly use dependability
                  analysis techniques. It explores service privileges
                  as being the main targets for attackers, and the
                  tunable parameters for intrusion response. The
                  approach presented in this paper is implemented as a
                  simulation-based framework and demonstrated for the
                  example of a vehicle reservation service.}
}
@inproceedings{kheir2010service,
  title = {A service dependency model for cost-sensitive
                  intrusion response},
  author = {Kheir, Nizar and Cuppens-Boulahia, Nora and Cuppens,
                  Fr{\'e}d{\'e}ric and Debar, Herv{\'e}},
  pages = {626--642},
  year = 2010,
  isbn = {978-3-642-15496-6},
  booktitle = {Proceedings of the 15th European Symposium on
                  Research in Computer Security},
  location = {Athens, Greece},
  month = {September},
  volume = 6345,
  series = {Lecture Notes in Computer Science},
  editor = {Gritzalis, Dimitris and Preneel, Bart and
                  Theoharidou, Marianthi},
  doi = {10.1007/978-3-642-15497-3_38},
  url = {http://link.springer.com/chapter/10.1007%2F978-3-642-15497-3_38},
  publisher = {Springer Berlin Heidelberg},
  keywords = {intrusion detection, intrusion response, cost
                  evaluation, service dependencies},
  abstract = {Recent advances in intrusion detection and
                  prevention have brought promising solutions to
                  enhance IT security. Despite these efforts, the
                  battle with cyber attackers has reached a
                  deadlock. While attackers always try to unveil new
                  vulnerabilities, security experts are bounded to
                  keep their softwares compliant with the latest
                  updates. Intrusion response systems are thus
                  relegated to a second rank because no one trusts
                  them to modify system configuration during runtime.
                  Current response cost evaluation techniques do not
                  cover all impact aspects, favoring availability over
                  confidentiality and integrity. They do not profit
                  from the findings in intrusion prevention which led
                  to powerful models including vulnerability graphs,
                  exploit graphs, etc. This paper bridges the gap
                  between these models and service dependency models
                  that are used for response evaluation. It proposes a
                  new service dependency representation that enables
                  intrusion and response impact evaluation. The
                  outcome is a service dependency model and a complete
                  methodology to use this model in order to evaluate
                  intrusion and response costs. The latter covers
                  response collateral damages and positive response
                  effects as they reduce intrusion costs.}
}
@inproceedings{lacoste2012self,
  title = {Self-Defending Clouds: Myth and Realities},
  author = {Lacoste, Marc and Wailly, Aur{\'e}lien and Debar,
                  Herv{\'e}},
  booktitle = {Proceedings of C\&ESAR 2012},
  month = {November},
  year = {2012},
  keywords = {Cloud Security Supervision, Cloud Security
                  Management, Self- Defending Clouds, Cloud Threats,
                  Autonomic Security, IaaS Infrastructures},
  abstract = {Security is a growing concern as it remains the last
                  barrier to widespread adoption of cloud
                  environments. However, is today’s cloud security
                  Lucy in the Sky with Diamonds? Expected to be
                  strong, flexible, efficient, and simple?  But
                  surprisingly, being neither? A new approach, making
                  clouds self-defending , has been heralded as a
                  possible element of answer to the cloud protection
                  chal- lenge. This paper presents an overview of
                  today’s state and advances in the field of cloud
                  infrastructure self-defense. Four key
                  self-protection principles are iden- tified for IaaS
                  self-protection to be effective. For each layer,
                  mechanisms actually deployed to deliver security are
                  analyzed to see how well they fulfill those prin-
                  ciples. The main remaining research challenges are
                  also discussed to yield truly mature self-defending
                  clouds.}
}
@inproceedings{levillain2012one,
  title = {One Year of Internet SSL measurement},
  author = {Levillain, Olivier and {\'E}balard, Arnaud and
                  Morin, Benjamin and Debar, Herv{\'e} and others},
  booktitle = {Proceedings of the 28th Annual Computer Security
                  Applications Conference (ACSAC'2012)},
  year = 2012,
  isbn = {978-1-4503-1312-4},
  location = {Orlando, Florida},
  pages = {11--20},
  numpages = 10,
  url = {http://doi.acm.org/10.1145/2420950.2420953},
  doi = {10.1145/2420950.2420953},
  acmid = 2420953,
  publisher = {ACM},
  address = {New York, NY, USA},
  keywords = {HTTPS, SSL/TLS, X.509, certificates, internet
                  measure},
  abstract = {Over the years, SSL/TLS has become an essential part
                  of internet security. As such, it should offer
                  robust and state-of-the-art security, in particular
                  for HTTPS, its first application. Theoretically, the
                  protocol allows for a trade-off between secure
                  algorithms and decent performance. Yet in practice,
                  servers do not always support the latest version of
                  the protocol, nor do they all enforce strong
                  cryptographic algorithms.  To assess the quality of
                  HTTPS servers in the wild, we enumerated HTTPS
                  servers on the internet in July 2010 and July
                  2011. We sent several stimuli to the servers to
                  gather detailed information. We then analysed some
                  parameters of the collected data and looked at how
                  they evolved. We also focused on two subsets of TLS
                  hosts within our measure: the trusted hosts
                  (possessing a valid certificate at the time of the
                  probing) and the EV hosts (presenting a trusted,
                  so-called Extended Validation certificate). Our
                  contributions rely on this methodology: the stimuli
                  we sent, the criteria we studied and the subsets we
                  focused on.  Moreover, even if EV servers present a
                  somewhat improved certificate quality over the TLS
                  hosts, we show they do not offer overall high
                  quality sessions, which could and should be
                  improved.}
}
@inproceedings{levillain2014parsifal,
  title = {Parsifal: writing efficient and robust binary
                  parsers, quickly},
  author = {Levillain, Olivier and Debar, Herv{\'e} and Morin,
                  Benjamin},
  booktitle = {Proceedings of the 8th International Conference on
                  Risks and Security of Internet and Systems
                  (CRISIS'2013)},
  year = 2013,
  month = {October},
  pages = {1-6},
  doi = {10.1109/CRiSIS.2013.6766344},
  url = {http://ieeexplore.ieee.org/xpl/mostRecentIssue.jsp?punumber=6749561},
  keywords = {parsers},
  abstract = {Parsers are pervasive software basic blocks: as soon
                  as a program needs to communicate with another
                  program or to read a file, a parser is
                  involved. However, writing robust parsers can be
                  difficult, as is revealed by the amount of bugs and
                  vulnerabilities related to programming errors in
                  parsers. In particular, network analysis tools can
                  be very complex to implement: for example, the
                  Wireshark project regularly publishes security
                  patches on its various dissectors. As security
                  researchers, we need robust tools on which we can
                  depend. The starting point of Parsifal was a study
                  of large amounts of SSL data. The data collected
                  contained legitimate SSL messages, as well as
                  invalid messages and other protocols (HTTP, SSH). To
                  face this challenge and extract relevant
                  information, we wrote several parsers, using
                  different languages, which resulted in Parsifal, an
                  OCaml-based parsing engine. Writing parsers and
                  analysing data not only helped us better understand
                  SSL/TLS, but also X.509 and BGP/MRT. More recently,
                  we have started studying Kerberos messages. The
                  contribution of Parsifal to security is
                  twofold. First we provide sound tools to analyse
                  complex file formats or network protocols. Secondly
                  we implement robust detection/sanitization
                  systems. The goal of this tutorial is to present
                  Parsifal and to use it to write a network protocol
                  parser (DNS) and a file format parser (PNG). The PNG
                  parser will then be used to build a PNG
                  sanitizer. Alternatively, an X.509 certificate
                  signing request validator can be implemented.}
}
@article{me2010new,
  title = {New Directions in Intrusion Detection and Alert
                  Correlation},
  author = {M{\'e}, Ludovic and Debar, Herv{\'e}},
  journal = {Information Interaction Intelligence (I3)},
  volume = 10,
  number = 1,
  pages = {11--31},
  year = 2010,
  publisher = {C{\'e}padu{\`e}s},
  keywords = {intrusion detection, correlation, diagnosis, test},
  abstract = {In this paper, we examine the current state of
                  research and commercial technology in intrusion
                  detection.We derive issues that need to be studied
                  by the research community to make progress in the
                  field and propose 13 possible research directions
                  and solutions to the problems or shortcomings
                  identified. }
}
@inproceedings{mustapha2012limitation,
  title = {Limitation of Honeypot/Honeynet Databases to Enhance
                  Alert Correlation},
  author = {Mustapha, Yosra and D{\'e}bar, Herv{\'e} and Jacob,
                  Gr{\'e}goire},
  pages = {203--217},
  year = 2012,
  booktitle = {Proceedings of the 6th International Conference on
                  Mathematical Methods, Models and Architectures for
                  Computer Network Security (MMM-ACNS'2012)},
  location = {St. Petersburg, Russia},
  month = {October},
  isbn = {978-3-642-33703-1},
  volume = 7531,
  series = {Lecture Notes in Computer Science},
  editor = {Kotenko, Igor and Skormin, Victor},
  doi = {10.1007/978-3-642-33704-8_18},
  url = {http://dx.doi.org/10.1007/978-3-642-33704-8_18},
  publisher = {Springer Berlin Heidelberg},
  keywords = {intrusion detection, alert correlation, honeypots},
  abstract = {In SIEM environments, security analysts process
                  massive amount of alerts often imprecise. Alert
                  correlation has been designed to efficiently analyze
                  this large volume of alerts. However, a major
                  limitation of existing correlation techniques is
                  that they focus on the local knowledge of alerts and
                  ignore the global view of the threat landscape. In
                  this paper, we introduce an alert enrichment
                  strategy that aims at improving the local domain
                  knowledge about the event with relevant global
                  information about the threat in order to enhance the
                  security event correlation process.  Today, the most
                  prominent sources of information about the global
                  threat landscape are the large honeypot/honeynet
                  infrastructures which allow us to gather more
                  in-depth insights on the modus operandi of attackers
                  by looking at the threat dynamics. In this paper, we
                  explore four honeypot databases that collect
                  information about malware propagation and security
                  information about web-based server profile. We
                  evaluate the use of these databases to correlate
                  local alerts with global knowledge. Our experiments
                  show that the information stored in current honeypot
                  databases suffers from several limitations related
                  to: the interaction level of honeypots that
                  influences their coverage and their analysis of the
                  attacker’s activities, collection of raw data which
                  may include imprecise or voluminous information, the
                  lack of standardization in the information
                  representation which hinder cross-references between
                  different databases, the lack of documentation
                  describing the available information.}
}
@incollection{mustapha2013service,
  title = {Service Dependencies-Aware Policy Enforcement
                  Framework Based on Hierarchical Colored Petri Net},
  author = {Mustapha, Yosra Ben and Debar, Herv{\'e}},
  booktitle = {Proceedings of the International Symposium on
                  Security in Computing and Communications
                  (SSCC'2013)},
  location = {Mysore, India},
  month = {August},
  pages = {313--321},
  year = 2013,
  publisher = {Springer Berlin Heidelberg},
  isbn = {978-3-642-40575-4},
  volume = 377,
  series = {Communications in Computer and Information Science},
  editor = {Thampi, SabuM. and Atrey, PradeepK. and Fan, Chun-I
                  and Perez, Gregorio-Martinez},
  doi = {10.1007/978-3-642-40576-1_31},
  url = {http://dx.doi.org/10.1007/978-3-642-40576-1_31},
  keywords = {intrusion detection, alert correlation, intrusion
                  response},
  abstract = {As computer and network security threats become more
                  sophisticated and the number of service dependencies
                  is increasing, optimal response decision is becoming
                  a challenging task for security administrators. They
                  should deploy and implement proper network security
                  policy enforcement mechanisms in order to apply the
                  appropriate countermeasures and defense strategy.
                  In this paper, we propose a novel modeling framework
                  which considers the service dependencies while
                  identifying and selecting the appropriate Policy
                  Enforcement Points during an intrusion response
                  process. First, we present the security implications
                  of the service dependencies that have been developed
                  in the literature. Second, we give an overview of
                  Colored Petri Nets (CPN) and Hierarchical CPN (HCPN)
                  and its application on network security. Third, we
                  specify our Service Dependencies-aware Policy
                  Enforcement Framework which is based on the
                  application of HCPN. Finally and to illustrate the
                  advantage of our approach, we present a webmail
                  application use case with the integration of
                  different Policy Enforcement Points.}
}
@inproceedings{rieke2012challenges,
  title = {Challenges for Advanced Security Monitoring--The
                  MASSIF Project},
  author = {Rieke, Roland and Prieto, Elsa and Diaz, Rodrigo and
                  Debar, Herv{\'e} and Hutchison, Andrew},
  booktitle = {Proceedings of the 9th International on Conference
                  Trust, Privacy and Security in Digital Business
                  (TrustBus 2012)},
  location = {Vienna, Austria},
  month = {September},
  pages = {222--223},
  year = 2012,
  publisher = {Springer Berlin/Heidelberg},
  isbn = {978-3-642-32286-0},
  volume = 7449,
  series = {Lecture Notes in Computer Science},
  editor = {Fischer-Hübner, Simone and Katsikas, Sokratis and
                  Quirchmayr, Gerald},
  doi = {10.1007/978-3-642-32287-7_23},
  url = {http://dx.doi.org/10.1007/978-3-642-32287-7_23},
  keywords = {security information and event management, SIEM,
                  intrusion detection},
  abstract = {The vision of creating a next-generation Security
                  Information and Event Management environment drives
                  the development of an architecture which provides
                  for trustworthy and resilient collection of security
                  events from source systems, processes and
                  applications.  A number of novel inspection and
                  analysis techniques are applied to the events
                  collected to provide high-level situational security
                  awareness, not only on the network level but also at
                  the service level where high-level threats such as
                  money laundering appear. An anticipatory impact
                  analysis will predict the outcome of threats and
                  mitigation strategies and thus enable proactive and
                  dynamic response.}
}
@article{schoo2011challenges,
  title = {Challenges for Cloud Networking Security},
  author = {Schoo, Peter and Fusenig, Volker and Souza, Victor
                  and Melo, M{\'a}rcio and Murray, Paul and Debar,
                  Herv{\'e} and Medhioub, Houssem and Zeghlache,
                  Djamal},
  journal = {Mobile Networks and Management - Revised Selected
                  Papers of the Second International ICST Conference
                  (MONAMI'2010)},
  location = {Santander, Spain},
  pages = {298--313},
  year = 2011,
  isbn = {978-3-642-21443-1},
  volume = 68,
  series = {Lecture Notes of the Institute for Computer
                  Sciences, Social Informatics and Telecommunications
                  Engineering},
  editor = {Pentikousis, Kostas and Agüero, Ramón and
                  García-Arranz, Marta and Papavassiliou, Symeon},
  doi = {10.1007/978-3-642-21444-8_26},
  url = {http://dx.doi.org/10.1007/978-3-642-21444-8_26},
  publisher = {Springer Berlin Heidelberg},
  keywords = {Cloud Networking, Cloud Computing, Network
                  Virtualisation, Security},
  abstract = {Cloud computing is widely considered as an
                  attractive service model since the users commitments
                  for investment and operations are minimised, and
                  costs are in direct relation to usage and
                  demand. However, when networking aspects for
                  distributed clouds are considered, there is little
                  support and the effort is often underestimated. The
                  project SAIL is addressing cloud networking as the
                  combination of management for cloud computing and
                  vital networking capabilities between distributed
                  cloud resources involved to improve the management
                  of both. This position paper presents new security
                  challenges as considered in SAIL for ensuring
                  legitimate usage of cloud networking resources and
                  for preventing misuse.}
}
@inproceedings{wailly2011towards,
  title = {Towards Multi-Layer Autonomic Isolation of Cloud
                  Computing and Networking Resources},
  author = {Wailly, Aur{\'e}lien and Lacoste, Marc and Debar,
                  Herv{\'e}},
  booktitle = {Proceedings of the 2011 Conference on Network and
                  Information Systems Security (SAR-SSI'2011)},
  pages = {1--9},
  year = 2011,
  organization = {IEEE},
  url = {http://aurelien.wail.ly/publications/sarssi-2011.pdf},
  keywords = {cloud computing, computer network security, IaaS
                  infrastructure, administration, cloud computing,
                  cloud resource isolation, flexible approach,
                  multilayer autonomic isolation, networking
                  resources, reconciling computing, security
                  components, Cloud computing, Complexity theory,
                  Computer architecture, Data privacy, Security,
                  Virtual machine monitors, Virtual private networks},
  abstract = {This paper describes a flexible approach to manage
                  autonomically cloud resource isolation between
                  different layers of an IaaS infrastructure,
                  reconciling computing and network views. The
                  corresponding framework overcomes fragmentation of
                  security components and automates their
                  administration by orchestrating different autonomic
                  loops, vertically (between layers) and horizontally
                  (between views).}
}
@inproceedings{wailly2012kungfuvisor,
  title = {KungFuVisor: enabling hypervisor self-defense},
  author = {WAILLY, Aurelien and Lacoste, Marc and DEBAR,
                  Herv{\'e}},
  booktitle = {EuroDW'12: The 6th EuroSys Doctoral Workshop},
  year = 2012,
  location = {Bern, Switzerland},
  url = {http://aurelien.wail.ly/publications/eurodw-2012.pdf},
  abstract = {Recently, some of the most potent attacks against
                  cloud computing infrastructures target their very
                  foundation: the hypervisor or Virtual Machine
                  Monitor (VMM). In each case, the main attack vector
                  is a poorly confined device driver in the
                  virtualization layer, enabling to bypass resource
                  isolation and take complete infrastructure
                  control. Current architectures offer no protection
                  against such attacks. At best, they attempt to
                  contain but do not eradicate the detected threat,
                  usually with static, hard-to-manage defense
                  strategies.  This paper proposes an altogether
                  different approach by presenting KungFuVisor, a
                  framework to build self-defending hypervisors.  The
                  framework regulates hypervisor protection through
                  several coordinated autonomic security loops which
                  supervise different VMM layers through well-defined
                  hooks. Thus, interactions between a device driver
                  and its VMM environment may be strictly monitored
                  and controlled automatically. The result is a very
                  flexible self-protection architecture, enabling to
                  enforce dynamically a rich spectrum of remediation
                  actions over different parts of the VMM, also
                  facilitating defense strategy administration.}
}
@inproceedings{wailly2012vespa,
  title = {VESPA: multi-layered self-protection for cloud
                  resources},
  author = {Wailly, Aur{\'e}lien and Lacoste, Marc and Debar,
                  Herv{\'e}},
  booktitle = {Proceedings of the 9th International Conference on
                  Autonomic Computing (ICAC '12)},
  pages = {155--160},
  year = 2012,
  isbn = {978-1-4503-1520-3},
  location = {San Jose, California, USA},
  numpages = 6,
  url = {http://doi.acm.org/10.1145/2371536.2371564},
  doi = {10.1145/2371536.2371564},
  acmid = 2371564,
  publisher = {ACM},
  address = {New York, NY, USA},
  keywords = {autonomic computing, cloud security, iaas,
                  self-protection},
  abstract = {Self-protection has recently raised growing interest
                  as possible element of answer to the cloud computing
                  infrastructure protection challenge. Faced with
                  multiple threats and heterogeneous defense
                  mechanisms, the autonomic approach proposes simpler,
                  stronger, and more efficient cloud security
                  management. Yet, previous solutions fall at the last
                  hurdle as they overlook key features of the cloud,
                  by lack of flexible security policies, cross-layered
                  defense, multiple control granularities, and open
                  security architectures. This paper presents VESPA, a
                  self-protection architecture for cloud
                  infrastructures overcoming such limitations. VESPA
                  is policy-based, and regulates security at two
                  levels, both within and across infrastructure
                  layers. Flexible coordination between
                  self-protection loops allows enforcing a rich
                  spectrum of security strategies such as cross-layer
                  detection and reaction. A multi-plane extensible
                  architecture also enables simple integration of
                  commodity detection and reaction
                  components. Evaluation of a VESPA implementation
                  shows that the design is applicable for effective
                  and flexible self-protection of cloud
                  infrastructures.}
}
@inproceedings{waillyretrovisor,
  title = {RetroVisor: Nested Virtualization for Multi IaaS VM},
  author = {Wailly, Aur{\'e}lien and Lacoste, Marc and Debar,
                  Herv{\'e}},
  booktitle = {Conf\'erence d'informatique en Parall{\'e}lisme,
                  Architecture et Syst{\`}eme},
  year = 2013,
  url = {http://aurelien.wail.ly/publications/compas-2013.pdf},
  abstract = {Nested virtualization provides an extra layer of
                  virtualization to enhance security with fairly
                  reasonable performance impact. Usercentric vision of
                  cloud computing gives a high-level of control on the
                  whole infrastructure, such as untrusted dom0.  This
                  paper introduces RetroVisor, a security architecture
                  to seamlessly run a virtual machine (VM) on multiple
                  hypervisors simultaneously.  We argue that this
                  approach delivers high-availability and provides
                  strong guarantees on multi IaaS infrastructures. The
                  user can perform detection and remediation against
                  potential hypervisors weaknesses, unexpected
                  behaviors and exploits.}
}
@inproceedings{wazan2013attribute,
  title = {Attribute-based Mining Process for the
                  Organization-Based Access Control Model},
  author = {Wazan, Ahmad Samer and Blanc, Gregory and Debar,
                  Herv{\'e} and Garcia-Alfaro, Joaquin},
  booktitle = {Proceedings of the 12th IEEE International
                  Conference on Trust, Security and Privacy in
                  Computing and Communications (TrustCom'2013 },
  pages = {421--430},
  year = 2013,
  organization = {IEEE},
  doi = {10.1109/TrustCom.2013.53},
  month = {July},
  keywords = {authorisation, data mining, OrBAC model, abstract
                  concepts, abstraction objective, attribute-based
                  mining process, organization-based access control
                  model, security access control models, security
                  policies, Abstracts, Access control, Concrete,
                  Context, Organizations, Permission, Access Control,
                  Policy Management, Role Mining, Security},
  abstract = {Since the late 60's, different security access
                  control models have been proposed. Their rationale
                  is to conceive high level abstract concepts that
                  permit to manage the security policies of
                  organizations efficiently. However, enforcing these
                  models is not a straightforward task, especially
                  when they do not consider the reality of
                  organizations which may have ad-hoc security
                  policies already deployed. Another issue is the
                  vagueness of their abstract concepts. We propose to
                  bridge the gap between the theory of access control
                  models and the reality of organizations by defining
                  an attribute-based mining process that deduce the
                  abstract concepts starting from the attribute
                  level. Additionaly, the attributes allow us to
                  semantically enrich the obtained results. We have
                  selected the Organization-Based Access Control
                  (OrBAC) model as the abstraction objective of our
                  study.}
}