The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
To make full use of space/air resources, a Space-Air Integrated Network (SAIN) which is a hierarchical network with satellites, airships and hovering Unmanned Aerial Vehicles (UAVs) is constructed. Nowadays, Free Space Optical (FSO) links have been widely applied in SAINs since they provide high-rate and large-capacity data transmission. Unfortunately, the FSO links across the atmosphere would perform...
Determining an optimal placement for active measurement points in an arbitrary network topology is challenging. Software-defined infrastructure and the virtualization of network functions imply that re-optimized placement is needed frequently to keep up with dynamic changes in the infrastructure. We present a novel genetic algorithm that was defined for optimizing the placement of active measurement...
Network Function Virtualization (NFV) is promising to lower the network operator's capital expenditure and operational expenditure by replacing proprietary hardware-based network equipment with software-based virtual network functions that can be consolidated into telecom clouds. In particular, NFV provides an efficient way to deploy network services using service function chains that consist of a...
Load-balancing and network optimization in SDN networks require efficient flow splitting during the path computation phase. The way flow splitting is typically implemented in switches is to map the output of an hash function computed on the headers of incoming flows to the content stored in a Ternary Content Addressable Memory (TCAM), a very efficient but scarce resource. Although a large TCAM budget...
In fat-tree data center networks, routing a packet from its source to destination includes two phases, upstream (i.e. from source to watershed switch) and downstream (i.e. from watershed switch to destination). The throughput/non-blocking performance of networks hinges much on the effects of two phases above. In this paper, we propose a new routing algorithm called Global Round Robin (GRR) for fat-tree...
In recent years a large number of LEO (Low Earth Orbit) satellites have been launched into space for various applications, such as weather forecast, environment monitoring and military surveillance. One important task of these satellites is to collect data and download them to Earth Stations (ESs) for further processing. Since LEO satellites fly at high speeds and have very limited contact time with...
This work provides an analysis of topological uncertainty in wireless networks. Here, we model a wireless network as a random geometric graph (RGG) and quantify topological uncertainty in terms of the Shannon entropy of the underlying graph model. Direct pairwise connections between nodes are probabilistic in general, and thus our analysis covers cases where channel randomness contributes to uncertainty...
Betweenness centrality is a popular metric in social science, and recently it was adopted also in computer science. Betweenness identifies the node, or the nodes, that are most suitable to perform critical network functions, such as firewalling and intrusion detection. However, computing centrality is resource-demanding, we can not give for granted that it can be computed in real time at every change...
Link capacity dimensioning is the periodic task where ISPs have to make provisions for sudden traffic bursts and network failures to assure uninterrupted operations. This provision comes in the form of link working capacities with noticeable amounts of headroom, i.e., spare capacities that are used in case of congestions or network failures. Distributed routing protocols like OSPF provide convergence...
This paper proposes the Topology-aware Virtual Machine Selection (TAVMS) algorithm to choose sets of communicating groups of virtual machines (VMs) to be migrated to other data centers, aiming at global energy savings. It considers the migration of groups of VMs as well as the data center network topology, selecting VM groups with network proximity in order to increase the potential number of equipments...
As faster storage devices become commercially viable alternatives to disk drives, the network is increasingly becoming the bottleneck in achieving good performance in distributed storage systems. This is especially true for erasure coded storage, where the reconstruction of lost data can significantly encumber the system. Thus, a significant amount of research has focused on reducing the amount of...
As online social networks grow in both size and connectivity, epidemic information dynamics in such networks is attracting considerable research interests, due to its impact on both the network and individuals. This paper studies control of malicious information (virus) epidemic with replicable antidote information, taking topological characteristics of the underlying graph into consideration. Specifically,...
With the proliferation of cloud computing and the expected requirements of future Internet of Things (IoT) and 5G network scenarios, more efficient and scalable Data Centers (DCs) will be required, offering very large pools of computational resources and storage capacity cost-effectively. Looking at todays' commercial DCs, they tend to rely on well-defined leaf-spine Data Center Network (DCN) topologies...
The routing and spectrum assignment (RSA) problem has emerged as the key design and control problem in elastic optical networks. Distance adaptive spectrum allocation exploits the tradeoff between spectrum width and reach to improve resource utilization by tailoring the modulation format to the level of impairments along the path. In this paper, we consider the distance-adaptive RSA (DA-RSA) problem...
Multipath routing, which is increasingly common in today's Internet, can lead two end-hosts to own multiple routing paths. This will impose adverse effects on most of the current network measurement methods, as they generally need to assume a single active path between any pair of end-hosts at any given time. In this paper, we attempt to identify whether multipath routing exists between two end-hosts...
Software Defined Networking (SDN) is an emerging paradigm for network design and management. By providing network programmability and separation of control and data planes, SDN offers salient features such as simplified and centralized management and control, reduced complexity and accelerated innovation. However, SDN introduces new challenges that should be addressed properly in order to benefit...
With the increasing popularity of cloud computing, the huge amount of energy consumed by data centers has gained much attention. Current proposals address the energy efficiency problem by two major methods: optimizing the allocation of physical servers and network elements (routers or switches). In order to improve resource utilization and minimize the energy consumption, the former method focuses...
Being considered as a key enabler for beyond 4G networks, Cloud-RAN (CRAN) offers advanced cooperation and coordinated processing capabilities and brings multiplexing gains. The high capacity and low latency fronthaul (FH) links requirement in the CRAN architecture can be reduced by a ?exible functional split of baseband processing between remote radio units (RRUs) and Baseband units (BBUs). Under...
Traffic engineering (TE) has long been used by network providers to reduce network congestion and improve resource utilization. Due to its significance, several traffic engineering algorithms have been proposed in literature. However, most of these algorithms optimize maximum link utilization (MLU) in network, and/or assume that network has the capability to route demands on arbitrary paths. Optimizing...
Abstract-In this paper, we develop a flexible and accurate analytical model of large networks with random base station (BS) placement, in order to understand the impact of key network parameters like BS density and load on the network performance. The main goal is to understand the flow level dynamics of such a system, assuming non-saturated users and studying the congestion statistics for BSs and...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.