Work in Progress: Scan Surveillance in Internet Networks

Abstract. In recent years, many measurement studies have shown the ubiquity of scanning activities in the Internet and the growing sophistication of probing techniques that became more stealthy by stretching slowly over time or using spoofed source IP addresses. Scans are mainly generated by attackers trying to map the configuration of a target network and by computer worms trying to spread over the Internet. Although, the problem of scan detection has been given a lot of attention by network security researchers, current state-of-the-art methods still suffer from high percentage of false alarms or low ratio of scan detection. In this paper, we propose to detect changes in scanning patterns, by monitor variation of the distribution of scan features in a space spanned by IP source address, IP destination address, source port number, and destination port number. This gives insight on characteristics of scanning activities and exposes the presence of emerging scanning attacks and worms. For that, we propose to use an information theoretic-based approach to detect changes in distributions

Traffic anomaly detection and characterization in the tunisian national university network

Abstract. Traffic anomalies are characterized by unusual and significant changes in a network traffic behavior. They can be malicious or unintentional. Malicious traffic anomalies can be caused by attacks, abusive network usage and worms or virus propagations. However unintentional ones can be caused by failures, flash crowds or router misconfigurations. In this paper, we present an anomaly detection system derived from the anomaly detection schema presented by Mei-Ling Shyu i

Transmission applicative multipoint pour les réseaux ad-hoc

AOMP (Ad-hoc Overlay Multicast Protocol) est une nouvelle approche pour la transmission applicative multipoint dans les réseaux ad-hoc mobiles. En exploitant les propriétés de routage IP, nous introduisons, dans une première étape, un algorithme distribué de correspondance des chemins permettant d'extraire des informations sur la topologie physique. Dans une seconde étape, nous construisons un arbre de transmission efficace à moindre coûts et s'adaptant à la mobilité des noeuds ad-hoc. Nous mettons en place un algorithme de raffinement pour améliorer les performances globales de la structure AOMP en cours de transmission. Les résultats de simulations montrent que AOMP, comparé à de récents protocoles multipoints applicatifs, diminue le délai de transmission, évite les redondances de paquets sur un même lien physique avec peu de pertes, en particulier en cas de mobilité des noeuds ad-hoc

Benchmarking national communications regulatory authority websites, 2010

Out of a total of 54 countries in Africa, 30 had regulatory institutions that could be classified as independent with websites. The analysis provides a summarized overview, ranking the online component of information provision and facilitation of regulatory processes. Benchmarking documents the incidence of aspects that are important for a regulator’s web presence across the categories of providing basic information and responsiveness; factual information about the national telecom sector; consumer and citizen information including universal service and complaints procedures; business related information and forms; and information about the regulator and regulatory processes

Revue de performance du secteur des TIC Tunisie, 2009/2010

Version anglaise disponible dans la Bibliothèque numérique du CRDI: Tunisia ICT sector performance review, 2009/201

Tunisia ICT sector performance review, 2009/2010

French version available in IDRC Digital Library: Revue de performance du secteur des TIC Tunisie, 2009/2010This analysis aims to enable telecom sector development. In 2010 the competitive landscape is characterized by a duopoly situation on the fixed-line level, a one-year monopoly for services linked to 3G, the intervention of three operators on the mobile level, and five private ISPs with one operator. Despite the fact that the liberalization experience is relatively young (dating from the beginning of 2000), gains have been remarkable, particularly in the fields of skills development and job creation. With the entrance of a third operator, the telecom sector advances towards a new development stage with diversification and innovative services

Hierarchical Routing for Large Networks -- Performance evaluation and optimization

... This paper deals with the specification, analysis and evaluation of some hierarchical routing procedures which are effective for large store-and-forward packet-switched computer networks. The procedures studied ate an extension of present techniques and rely on a hierarchical clustering of the network nodes. In particular, optimal clustering structures are determined so as to minimize the length of the routing tables required. A price for reducing the table length is the increase in the average message path length in the network. Bounds are derived to evaluate the maximum increase in path length for a given table length. From this we obtain our key result, namely, that in the limit of a very large network, enormous table reduction may be achieved with essentially no increase in network path length