Search results for "Network service"
showing 10 items of 10 documents
Energy efficient resource allocation in heterogeneous software defined network: A reverse combinatorial auction approach
2015
In this paper, resource allocation for energy effi- ciency in heterogeneous Software Defined Network (SDN) with multiple network service providers (NSPs) is studied. The considered problem is modeled as a reverse combinatorial auction game, which takes different quality of service (QoS) requirements into account. The heterogeneous network selection associated with power allocation problem is optimized by maximizing the energy efficiency of data transmission. By exploiting the properties of fractional programming, the resulting non-convex Winner Determination Problem (WDP) is transformed into an equivalent subtractive convex optimization problem. The proposed reverse combinatorial auction ga…
UML-Based Reliability Modeling of Network Services, a UDP Echo Service Case Study
2009
In the paper, we discuss state space reliability modeling formalism of distributed systems and services compliant with UML metamodel. Behavior of modeled application system we describe in terms of states. Service generation process we represent as a sequence of application system states. State space approach allows us to define dependence between application system components via dependence between components states and states input, output parameters. Reliability of application system component we define for each simply action state. Reliability of a service we express by components reliability in states determined by service generation process. As an example, we analyze reliability of cli…
A New Multicast Technique for Video Transmission over ABR Services in ATM Networks
2000
Multicast techniques are the only way to simultaneously provide flows of information from one source to several destinations. The intention of this paper is to study and to evaluate different multicast techniques using a video coder based on an adaptive video compression algorithm with subband coding and a best effort network service like ATM with the Available Bit Rate (ABR) service. This video transmission can adapt faster and easily to changing network conditions. In this way, we present an evaluation process for a determined network configuration. Thereafter we discuss the results obtained by simulation and propose for this video transmission a trade-off between these multicast techniqu…
Anomaly Detection Algorithms for the Sleeping Cell Detection in LTE Networks
2015
The Sleeping Cell problem is a particular type of cell degradation in Long-Term Evolution (LTE) networks. In practice such cell outage leads to the lack of network service and sometimes it can be revealed only after multiple user complains by an operator. In this study a cell becomes sleeping because of a Random Access Channel (RACH) failure, which may happen due to software or hardware problems. For the detection of malfunctioning cells, we introduce a data mining based framework. In its core is the analysis of event sequences reported by a User Equipment (UE) to a serving Base Station (BS). The crucial element of the developed framework is an anomaly detection algorithm. We compare perfor…
An efficient distributed algorithm for generating and updating multicast trees
2006
As group applications are becoming widespread, efficient network utilization becomes a growing concern. Multicast transmission represents a necessary lower network service for the wide diffusion of new multimedia network applications. Multicast transmission may use network resources more efficiently than multiple point-to-point messages; however, creating optimal multicast trees (Steiner Tree Problem in networks) is prohibitively expensive. This paper proposes a distributed algorithm for the heuristic solution of the Steiner Tree Problem, allowing the construction of effective distribution trees using a coordination protocol among the network nodes. Furthermore, we propose a novel distribut…
Exploring social media network landscape of post-Soviet space
2019
The “post-Soviet space” consists of countries with a substantial fraction of the world’s population; however, unlike many other regions, its social media network landscape is still somewhat under-explored. This paper aims at filling this gap. To this purpose, we use anonymized data on user friendships at VK.com (also known as VKontakte and, informally, as “Russian Facebook”), which is the largest and most popular social media portal in the post-Soviet space with hundreds of millions of user accounts. Using the VK network snapshots from October 2015 to December 2016, we conduct a “multiscale” empirical study of this network by considering conn…
Personal branding or employee advocacy : expert's use of social networking site
2017
This paper deals with social media in building experts’ professional images. In the theoretical part, online communities are discussed in the light of the paper’s topic. The study relies on technological adoption models, and in particular, the UTAUT (Unified Theory of Acceptance and Use of Technology) 2 model. In the empirical part, the use of LinkedIn was analyzed as the major tool for professional networking. Our research results suggest that the use of LinkedIn has been initiated mostly by invitation or encouragement of another user. Only in rare occasions, self-branding was reported as the primary motivation to register into LinkedIn. Self-presentation was improved in the process of usi…
Deployment of a WLCG network monitoring infrastructure based on the perfSONAR-PS technology
2014
The WLCG infrastructure moved from a very rigid network topology, based on the MONARC model, to a more relaxed system, where data movement between regions or countries does not necessarily need to involve T1 centres. While this evolution brought obvious advantages, especially in terms of flexibility for the LHC experiment's data management systems, it also opened the question of how to monitor the increasing number of possible network paths, in order to provide a global reliable network service. The perfSONAR network monitoring system has been evaluated and agreed as a proper solution to cover the WLCG network monitoring use cases: it allows WLCG to plan and execute latency and bandwidth te…
Application of Zero Exclusion Condition to Stability Analysis of Computer Networks
2016
Stability, or robust [Dscr ]-stability analysis of computer network considered as a dynamic system, relies on increasing the speed of data transmission while minimizing the queuing time delays of its packets in the router buffers that can affect the overall data flow of the network traffic. We consider a zero exclusion condition as an effective method for testing and analyzing the computer networks stability. Our findings indicate that keeping control over the queuing time delays as well as including some factors of the RED algorithm and its variants, which we present in this paper, can improve the quality of network services significantly. Our method can be applicable both to single-loop a…
An analytical model of a new packet marking algorithm for TCP flows
2005
In Differentiated Services networks, packets may receive a different treatment according to their Differentiateo Services Code Point (DSCP) label. As a consequence, packet marking schemes can also be devised to differentiate packets belonging to a same TCP flow, with the goal of improving the performance experienced. This paper presents an analytical model for an adaptive packet marking scheme proposed in our previous work. The model combines three specific sub-models aimed at describing (i) the TCP sources aggregate, (ii) the marker, and (iii) the network status. Preliminary simulation results show quite accurate predictions for throughput and average queue occupancy. Besides, the research…