1,721,091 research outputs found
Real-Time Communications in the Web: Issues, Achievements, and Ongoing Standardization Efforts
No full textWeb Real-Time Communication (WebRTC) is an upcoming standard that aims to enable real-time communication among Web browsers in a peer-to-peer fashion. The IETF RTCWeb and W3C WebRTC working groups are jointly defining both the APIs and the underlying communication protocols for setting up and managing a reliable communication channel between any pair of next generation Web browsers
On the effective exploitation of distributed information for cooperative network security and routing optimization.
No full textThe wide deployment of more and more sophisticated services and application over Internet imposes to careful project solutions for face the threats that this spreading involved. Unfortunately, the computer networks were de- signed neglecting the problem of security, since they ware thinking as "open systems" where anyone could use them as it liked, and malicious users was not considered. The lack of security requires to study alternative solutions that integrate the existing network technologies. The interest in computer network security is growing in the last year and new ideas have been proposed. In this thesis we present a cooperative approach to network security. By sharing information about evidence of anomalous user's activities it is possible to improve the effectiveness of the overall system by a careful prevention and detection of attacks. In this way the cooperation is able to overcome the intrinsic design limits of existing computer networks. By analyzing several collaborative systems, we de ne a general framework for the design and implementation of a reliable cooperative solution. Based on this framework, we implement two systems that share common project's principles: a cooperative DoS detection system and a new secure routing protocol for wireless networks. The results prove the goodness of design and the capability of framework proposed to be extended to several problems of network security
Multiple classifier systems for network security: from data collection to attack detection.
No full textSince the Internet started developing, hosts and provided services have always been targeted with attacks trying to disrupt them. Trends show that, throughout the years, the number of hosts, as well as the degree of dependency of the whole society on the services provided through the Internet, increased dramatically, whereas the skills and knowledge required to interfere with normal network operation, and eventually to abruptly interrupt it, decreased accordingly. This considerations urge the requirement for effective tools, aimed at granting security to Internet users. The need for systems capable of detecting attacks, and reacting in order to prevent them from occurring again, is nowadays undeniable. In this thesis we propose methods based on multiple classifier systems for intrusion detection. We use such systems for automated data collection, also taking privacy issues into account. Some approaches to traffic classification are presented too, together with a proposal for the practical deployment of multiple classifiers in a real network environment
A Link Weight Assignment Algorithm for Traffic-Engineered Networks
No full textIn this paper we address issues related to the definition of effective metrics for the application of load-balancing techniques inside providers’ core networks. We will present an original approach to the problem of assigning appropriate weights to the network links. The main contribution of our work resides in having devised a solution relying on a cost function which depends on link utilization in a non-linear fashion. The paper discusses the rationale behind the choice of such a cost function and provides some experimental results and preliminary performance analysis
An engineering approach to QoS provisioning over the Internet
No full textExisting communications systems are rapidly converging into an ubiquitous information infrastructure that does not distinguish between computing and communications, but rather provides a set of distributed services to the user. The research community must be prepared to foresee these changes and to deal with them, enlarging the space of technical possibilities so as to make available to society's needs new valuable choices. In this scenario the capability of the network to provide the applications with end-to-end Quality of Service (QoS) becomes a central issue. An engineering approach is needed in this research field in order to incrementally build the next-generation network. This paper focuses on some of the hot topics related to end-to-end QoS provisioning over the Internet and aims at exploiting the current proposals of the research community, while looking at them from a critical point of view and providing actual implementation of some of the discussed ideas. Thus, we propose a QoS-capable architecture aiming at providing flexible and effective implementation of the Integrated Services model via a Weighted Fair Queueing scheduling mechanism, while defining a new service class capable of giving long-term rate guarantees to Internet flows
REFACING: An autonomic approach to network security based on multidimensional trustworthiness
No full textSeveral research efforts have recently focused on achieving distributed anomaly detection
in an effective way. As a result, new information fusion algorithms and models have been
defined and applied in order to correlate information from multiple intrusion detection
sensors distributed inside the network. In this field, an approach which is gaining momentum
in the international research community relies on the exploitation of the Dempster–
Shafer (D–S) theory. Dempster and Shafer have conceived a mathematical theory of
evidence based on belief functions and plausible reasoning, which is used to combine separate
pieces of information (evidence) to compute the probability of an event.
However, the adoption of the D–S theory to improve distributed anomaly detection efficiency
generally involves facing some important issues. The most important challenge definitely
consists in sorting the uncertainties in the problem into a priori independent items
of evidence. We believe that this can be effectively carried out by looking at some of the
principles of autonomic computing in a self-adaptive fashion, i.e. by introducing support
for self-management, self-configuration and self-optimization functionality.
In this paper, we intend to tackle some of the above mentioned issues by proposing the
application of the D–S theory to network information fusion. This will be done by proposing
a model for a self-management supervising layer exploiting the innovative concept of
multidimensional reputation, which we have called REFACING (RElationship–FAmiliarity–Confidence–
INteGrity)
Optimised balancing algorithm for content delivery networks
No full textIn this study the authors present the ‘fictitiously starred optimised balancing’ (FSOB), a novel algorithm for load
balancing in a content delivery network (CDN) scenario. FSOB exploits the multiple redirection mechanism of the HTTP
protocol to optimally redistribute clients requests among the servers which build up the CDN. Load redistribution is aimed at
equalising the level of occupancy of the server queues and is achieved through the periodical exchange of information
computed locally at each node. The algorithm initially makes a fictitious assumption about the local topology of the network,
as it is seen by each single server node, which looks at itself as the centre (i.e. the master) of a star made up of all of its
neighbours (i.e. the slaves). Load redistribution is performed by the master which, if needed, appropriately redirects incoming
requests to its slaves. The authors show how FSOB outperforms most of its competitors under a number of fundamental
aspects, at the price of an increased overhead owing to the adoption of the multiple redirections mechanism for the
redistribution phase. Finally, they study the scalability properties of FSOB and perform a comparative evaluation of its
performance with respect to the most interesting existing solutions
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