Neighborhood Detection in Mobile Ad-Hoc Network Using Colored Petri Net

Colored Petri Nets (CPNs) [2] is a language for the modeling and validation of systems in which concurrency, communication [6], and synchronization play a major role. Colored Petri Nets is a discrete-event modeling language combining Petri nets with the functional programming language Standard ML. Petri nets provide the foundation of the graphical notation and the basic primitives for modeling concurrency, communication, and synchronization. Standard ML provides the primitives for the definition of data types, describing data manipulation, and for creating compact and parameterizable models. A CPN model of a system is an executable model representing the states of the system and the events (transitions) that can cause the system to change state [4]. The CPN language makes it possible to organize a model as a set of modules, and it includes a time concept for representing the time taken to execute events in the modeled system. In a mobile ad-hoc network(MANET) mobile nodes directly send messages to each other via wireless transmission. A node can send a message to another node beyond its transmission range by using other nodes as relay points, and thus a node can function as a router [1]. Typical applications of MANETS include defense systems such as battlefield survivability and disaster recovery. The research on MANETs originates from part of the Advanced Research Projects Agency(ARPA) project in the 1970s [1]. With the explosive growth of the Internet and mobile communication networks, challenging requirements have been introduced into MANETs and designing routing protocols has become more complex. One approach for ensuring correctness of an existing routing protocol is to create a formal model for the protocol and analyze the model to determine if indeed the protocol provides the defined service correctly. Colored Petri Nets are a suitable modeling language for this purpose as it can conveniently express non-determinism, concurrency and different levels of abstraction that are inherent in routing protocols. However, it is not easy to build a CPN model of a MANET because a node can move in and out of its transmission range and thus the MANET‟s topology dynamically changes. In this paper we propose an algorithm for addressing such mobility problem of a MANET [1]. Using this algorithm a node can find its neighbors ,which are dynamically changing, at any instant of time

Ontology-Based Workflow Validation

International audienceIn order to ensure a workflow to be executed correctly, many approaches were introduced. But not many of them consider the semantic correctness of the workflow in the design time and the run time. In this paper, a solution to check the semantic correctness of the workflow automatically is presented. To do that, the workflow must be represented in a machine understandable form, an ontology-based approach to represent a workflow is proposed. In addition, we also provide a set of changed operations allowing the users to customize a workflow for using in their organizations. Their change can be made while ensuring the correctness of the workflow. Moreover, a verification method is proposed for checking the semantic correctness of workflow

Optimiranje pakiranja paleta u distribucijskom centru pomoću obojenih Petrijevih mreža

The pallet packing process is a critical supply chain component for many distribution centers. Most pallet loading optimization tools provide very good solutions when boxes’ dimensions are practically quite uniform, which is the case of most production industrial systems, since they are used to work with a reduced number of master boxes. However, there are other systems such as distribution centers characterized by a high diversity of boxes to be fitted altogether in the same pallet. In this paper a Coloured Petri Net model that formalizes the Pallet Loading problem and its optimization by integrating evaluation methods with search methods will be presented. The model developed provides very good results by using certain heuristics that avoids the analysis of the whole search space, simulating only the best scenarios. The proposed approach can be used to integrate warehouse layout configuration, storage policy, distribution policy together with picking policy. As a result of the proposed strategy, considerable savings on transport resource costs can be achieved.Proces pakiranja paleta kritična je faza opskrbnog lanca u distribucijskim centrima. Većina alata za optimiranje pakiranja paleta daje vrlo dobre rezultate kada su dimenzije kutija ujednačene, što je često slučaj u industrijskim distribucijskim centrima, ali ne daju dobre rezultate u distribucijskim centrima s velikom neujednačenošću dimenzija kutija koje treba upakirati u jednu paletu. U radu su primijenjene obojene Petrijeve mreže, koje formaliziraju proces pakiranja palete i njegovu optimizaciju integracijom evaluacijskih metoda i metoda pretraživanja. Razvijeni model daje vrlo dobre rezultate uz primjenu određene heuristike kojom se pretraživanje svodi samo na najbolje scenarije umjesto pretraživanja čitavog prostora. Predloženi pristup može se koristiti za integraciju organizacije skladišta, strategije spremanja, strategije distribucije i strategije pakiranja, čime se mogu postići značajne uštede u transportnim troškovima

Validation of Routing Protocol for Mobile Ad Hoc Networks using Colored PetriNets

In a Mobile Ad Hoc Network (MANET), mobile nodes directly send messages to each other via other nodes in a wireless environment. A node can send a message to a destination node beyond its transmission range by using other nodes as relay points, and thus a node can function as a router. With the explosive growth of the Internet and mobile communication networks, challenging requirements have been introduced into MANETs and designing routing protocols has become more complex. For a successful application of MANETS, it is very important to ensure that a routing protocol is unambiguous, complete and functionally correct. One approach to ensuring correctness of an existing routing protocol is to create a formal model for the protocol, and analyze the model to determine if needed the protocol provides the defined service correctly. Colored Petri Nets (CPNs) are a suitable modeling language for this purpose, as it can conveniently express non-determinism , concurrency and different levels of abstraction that are inherent in routing protocols. However it is not easy to build a CPN model of a MANET because a node can move in and out of its transmission range and thus the MANET’s topology dynamically changes. So a topology approximation (TA) mechanism has been proposed to address this problem of mobility and perform simulations of routing protocol called Ad Hoc On demand Distance Vector Routing (AODV) and Distance Source Routing(DSR) and to perform comparison based on the simulation results

Third Workshop and Tutorial on Practical Use of Coloured Petri Nets and the CPN Tools, Aarhus, Denmark, August 29-31, 2001

This booklet contains the proceedings of the Third Workshop on Practical Use of Coloured Petri Nets and the CPN Tools, August 29-31, 2001. The workshop is organised by the CPN group at Department of Computer Science, University of Aarhus, Denmark. The papers are also available in electronic form via the web pages: http://www.daimi.au.dk/CPnets/workshop01

Feature interaction in composed systems. Proceedings. ECOOP 2001 Workshop #08 in association with the 15th European Conference on Object-Oriented Programming, Budapest, Hungary, June 18-22, 2001

Feature interaction is nothing new and not limited to computer science. The problem of undesirable feature interaction (feature interaction problem) has already been investigated in the telecommunication domain. Our goal is the investigation of feature interaction in componet-based systems beyond telecommunication. This Technical Report embraces all position papers accepted at the ECOOP 2001 workshop no. 08 on "Feature Interaction in Composed Systems". The workshop was held on June 18, 2001 at Budapest, Hungary

Second Workshop on Practical Use of Coloured Petri Nets and Design/CPN.

This report contains the proceedings of the Second Workshop on Practical Use of Coloured Petri Nets and Design/CPN, October 13-15, 1999. The workshop was organised by the CPN group at the Department of Computer Science at the University of Aarhus, Denmark. The individual papers are available in electronic form via the web pages: http://www.daimi.au.dk/CPnets/workshop99

A novel approach to emergency management of wireless telecommunication system

The survivability concerns the service continuity when the components of a system are damaged. This concept is especially useful in the emergency management of the system, as often emergencies involve accidents or incident disasters which more or less damage the system. The overall objective of this thesis study is to develop a quantitative management approach to the emergency management of a wireless cellular telecommunication system in light of its service continuity in emergency situations – namely the survivability of the system. A particular wireless cellular telecommunication system, WCDMA, is taken as an example to ground this research.The thesis proposes an ontology-based paradigm for service management such that the management system contains three models: (1) the work domain model, (2) the dynamic model, and (3) the reconfiguration model. A powerful work domain modeling tool called Function-Behavior-Structure (FBS) is employed for developing the work domain model of the WCDMA system. Petri-Net theory, as well as its formalization, is applied to develop the dynamic model of the WCDMA system. A concept in engineering design called the general and specific function concept is applied to develop a new approach to system reconfiguration for the high survivability of the system. These models are implemented along with a user-interface which can be used by emergency management personnel. A demonstration of the effectiveness of this study approach is included.There are a couple of contributions with this thesis study. First, the proposed approach can be added to contemporary telecommunication management systems. Second, the Petri Net model of the WCDMA system is more comprehensive than any dynamic model of the telecommunication systems in literature. Furthermore, this model can be extended to any other telecommunication system. Third, the proposed system reconfiguration approach, based on the general and specific function concept, offers a unique way for the survivability of any service provider system.In conclusion, the ontology-based paradigm for a service system management provides a total solution to service continuity as well as its emergency management. This paradigm makes the complex mathematical modeling of the system transparent to the manager or managerial personnel and provides a feasible scenario of the human-in-the-loop management

A model to study cyber attack mechanics and denial-of-service exploits over the internet\u27s router infrastructure using colored petri nets

The Internet‟s router infrastructure, a scale-free computer network, is vulnerable to targeted denial-of-service (DoS) attacks. Protecting this infrastructure‟s stability is a vital national interest because of the dependence of economic and national security transactions on the Internet. Current defensive countermeasures that rely on monitoring specific router traffic have been shown to be costly, inefficient, impractical, and reactive rather than anticipatory. To address these issues, this research investigation considers a new paradigm that relies on the systemic changes that occur during a cyber attack, rather than individual router traffic anomalies. It has been hypothesized in the literature that systemic knowledge of cyber attack mechanics can be used to infer the existence of an exploit in its formative stages, before severe network degradation occurs. The study described here targeted DoS attacks against large-scale computer networks. To determine whether this new paradigm can be expressed though the study of subtle changes in the physical characteristics of the Internet‟s connectivity environment, this research developed a first of its kind Colored Petri Net (CPN) model of the United States AT&T router connectivity topology. By simulating the systemic affects of a DoS attack over this infrastructure, the objectives of this research were to (1) determine whether it is possible to detect small subtle changes in the connectivity environment of the Internet‟s router connectivity infrastructure that occur during a cyber attack; and (2) if the first premise is valid, to ascertain the feasibility of using these changes as a means for (a) early infrastructure attack detection and (b) router infrastructure protection strategy development against these attacks. Using CPN simulations, this study determined that systemic network changes can be detected in the early stages of a cyber attack. Specifically, this research has provided evidence that using knowledge of the Internet‟s connectivity topology and its physical characteristics to protect the router infrastructure from targeted DoS attacks is feasible. In addition, it is plausible to use these techniques to detect targeted DoS attacks and may lead to new network security tools