Measuring inconsistency in a network intrusion detection rule set based on Snort

In this preliminary study, we investigate how inconsistency in a network intrusion detection rule set can be measured. To achieve this, we first examine the structure of these rules which are based on Snort and incorporate regular expression (Regex) pattern matching. We then identify primitive elements in these rules in order to translate the rules into their (equivalent) logical forms and to establish connections between them. Additional rules from background knowledge are also introduced to make the correlations among rules more explicit. We measure the degree of inconsistency in formulae of such a rule set (using the Scoring function, Shapley inconsistency values and Blame measure for prioritized knowledge) and compare the *This is a revised and significantly extended version of [1]

MUS-Based Partitioning for Inconsistency Measures

National audienceMesurer le degré d'incohérence des bases de connaissances permet aux agents une meilleur compréhension de leur environnement. Différentes approches sémantiques et syntaxiques ont été proposées pour quantifier l'incohérence. Dans ce papier, nous proposons d'analyser les limites des approches existantes. Tout d'abord, nous explorons la propriété logique d'additivité en considérant les composantes connexes du graphe représentant les bases de connaissances. Ensuite, nous montrons comment la structure de ce graphe peut être prise en compte pour identifier d'une manière plus fine la responsabilité de chaque formule dans l'incohérence. Finalement, nous étendons notre approche pour fournir une mesure d'incohérence de la base entière en satisfaisant des propriétés définies

Inconsistency Measurement based on Variables in Minimal Unsatisfiable Subsets

International audienceMeasuring inconsistency degrees of knowledge bases (KBs) provides important context information for facilitating inconsistency handling. Several semantic and syntax based measures have been proposed separately. In this paper, we propose a new way to define inconsistency measurements by combining semantic and syntax based approaches. It is based on counting the variables of minimal unsatisfiable subsets (MUSes) and minimal correction subsets (MCSes), which leads to two equivalent inconsistency degrees, named IDMUS and IDMCS. We give the theoretical and experimental comparisons between them and two purely semantic-based inconsistency degrees: 4-valued and the Quasi Classical semantics based inconsistency degrees. More- over, the computational complexities related to our new inconsistency measurements are studied. As it turns out that computing the exact inconsistency degrees is intractable in general, we then propose and evaluate an anytime algorithm to make IDMUS and IDMCS usable in knowledge management applications. In particular, as most of syntax based measures tend to be difficult to compute in reality due to the exponential number of MUSes, our new inconsistency measures are practical because the numbers of variables in MUSes are often limited or easily to be approximated. We evaluate our approach on the DC benchmark. Our encourag- ing experimental results show that these new inconsistency measure- ments or their approximations are efficient to handle large knowledge bases and to better distinguish inconsistent knowledge bases

Revisiting Postulates for Inconsistency Measures

Postulates for inconsistency measures are examined, the set of postulates due to Hunter and Konieczny being the starting point. Objections are raised against a few individual postulates. More general shortcomings are discussed and a new series of postulates is introduced

A compromise-negotiation framework based on Game theory for eliminating requirements inconsistency

Za bilo koji predloženi projekt razvoja softvera, neizbježno je suočiti se s promjenama zahtjeva tijekom razvoja softvera. Nekontrolirane promjene mogu dovesti do loše specifikacije zahtjeva, što čak može rezultirati propadanjem projekta. Rezultat toga je potreba za osiguranjem učinkovitog i fleksibilnog upravljanja promjenama zahtjeva i jedan od osnovnih zadataka je uklanjanje nedosljednosti u zahtjevima izazvanim promjenama. U ovom radu razmatramo postupak pregovora o specifikaciji novih i starih zahtjeva primjenom Teorije igara. Obje strane čine ustupke tijekom igre dok se ne postigne Nashova ravnoteža, tj. dok obje strane ne budu zadovoljne rezultatom pregovora. Točnije, najprije se niz zahtjeva predstavlja logičnom formulom. Tada se odvojeno predlaže metoda pregovora oko zahtjeva, utemeljena na miješanoj strategiji i čistoj strategiji Nashove ravnoteže, a također i okvirno načelo za postizanje kompromisa na temelju Teorije igara. Daje se i analiza slučaja u svrhu provjere učinkovitosti naše metode. Na kraju se daju usporedbe i zaključak.For any proposed software development project, it is inevitable to confront requirements changes during the software development life cycle. Uncontrolled changes may cause bad requirements specification, which even further leads to project’s failure. As a result, it is necessary to provide effective and flexible requirements change management. One of the kernel tasks of requirement change management is to eliminate requirement inconsistency caused by changes. In this paper, we consider negotiation process of the new and the old requirements specifications under Game theory. Both sides concession during the game process until the game achieves Nash equilibrium, i.e. both sides gain satisfied negotiation results. To be specific, firstly, the requirement set is represented in logical formula. Then a requirement conflict negotiation method based on mixed strategy and pure strategy Nash equilibrium is proposed separately, and a Compromise-Negotiation framework based on Game theory is presented as well. A case study will be given in the following part to verify our method’s effectiveness. Finally, it comes to a comparison and conclusion