Adel Bouhoula

2papers

2 Papers

CVOct 15, 2016
Incremental One-Class Models for Data Classification

Takoua Kefi, Riadh Ksantini, M. Becha Kaaniche et al.

In this paper we outline a PhD research plan. This research contributes to the field of one-class incremental learning and classification in case of non-stationary environments. The goal of this PhD is to define a new classification framework able to deal with very small learning dataset at the beginning of the process and with abilities to adjust itself according to the variability of the incoming data which create large scale datasets. As a preliminary work, incremental Covariance-guided One-Class Support Vector Machine is proposed to deal with sequentially obtained data. It is inspired from COSVM which put more emphasis on the low variance directions while keeping the basic formulation of incremental One-Class Support Vector Machine untouched. The incremental procedure is introduced by controlling the possible changes of support vectors after the addition of new data points, thanks to the Karush-Kuhn-Tucker conditions, that have to be maintained on all previously acquired data. Comparative experimental results with contemporary incremental and non-incremental one-class classifiers on numerous artificial and real data sets show that our method results in significantly better classification performance.

CRJul 16, 2012
Formal Checking of Multiple Firewalls

Nihel Ben Youssef Ben Souayeh, Adel Bouhoula

When enterprises deploy multiple firewalls, a packet may be examined by different sets of firewalls. It has been observed that the resulting complex firewall network is highly error prone and causes serious security holes. Hence, automated solutions are needed in order to check its correctness. In this paper, we propose a formal and automatic method for checking whether multiple firewalls react correctly with respect to a security policy given in a high level declarative language. When errors are detected, some useful feedback is returned in order to correct the firewall configurations. Furthermore, we propose a priority-based approach to ensure that no incoherencies exist within the security policy. We show that our method is both correct and complete. Finally, it has been implemented in a prototype of verifier based on a satisfiability solver modulo theories. Experiment conducted on relevant case studies demonstrates the efficiency of our approach.