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.
We consider the problem of dimensioning resilient backbone networks for cloud-like scenarios where demand is to be served at one among several candidate data centers (DCs), and where that demand varies over time, which we assume to be slotted. We thus consider multi-period traffic, for which we need to find routes to both a primary DC and a backup DC (in case the primary, or the network connection...
This paper proposes a new model that can represent the slot usage and the status of each possible slot groups in a flexible-grid optical network. This model facilitates visualizing the current network state in a graphical form as well as a proper data structure in the memory. It also promotes the design of new approaches for dynamic connection provisioning. The basic concepts of the model is illustrated...
Multicast is designed to jointly deliver content from a single source to a set of destinations. It can efficiently save the bandwidth consumption and reduce the load on the source. The appearance of SDN provides opportunities to deploy flexible protocols, including multicast and its variants. However, in many important applications, it is not necessary that the source of a multicast transfer has to...
In data storage systems, data are typically stored in redundant storage nodes to ensure storage reliability. When storage nodes fail, with the help of the redundant nodes, the lost data can be restored in new storage nodes. Such a regeneration process may be aborted, since storage nodes may fail during the process. Therefore, reducing the time of regeneration process is a well-known challenge to improve...
Big data processing applications have been migrated into cloud gradually, due to the advantages of cloud computing. Hadoop Distributed File System (HDFS), is one of the fundamental support systems for big data processing on MapReduce-like frameworks, such as Hadoop and Spark. However, the default block allocation scheme of HDFS doesn't fit well in the cloud environments behaving in two aspects: data...
The Secure Autonomous Response Networks (SARNET) framework introduces a mechanism to respond autonomously to security attacks in Software Defined Networks (SDN). Still the range of responses possible and their effectiveness need to be properly evaluated such that the decision making process and the self-learning capability of such systems are optimized. To this purpose we developed a touch-table driven...
In this paper, we introduce Mayflower, a new distributed filesystem that is co-designed from the ground up to work together with a network control plane. In addition to the standard distributed filesystem components, Mayflower has a flow monitor and manager running alongside a software-defined networking controller. This tight coupling with the network controller enables Mayflower to make intelligent...
Deploying cache has been generally adopted by Internet service providers (ISPs) to mitigate P2P traffic in recent years. Most traditional caching algorithms are designed for locality-unaware P2P networks, which mainly consider the requested frequency of contents as the principle of caching policies. However, in more prevalent locality-aware conditions with biased neighbor-selection policies, the existing...
As network complexity and heterogeneity have increased dramatically in the last decade, modern policy-based management techniques for adaptive routing decisions regarding path selection optimization and intelligent path control are necessary. In this paper, we analyze the application performance requirements, and the event-based management options for adaptive routing. Then, we propose an innovative...
In this paper, the performance of HTTP protocol and FTP Protocol is analyzed by using OPNET-based simulation. Firstly, related scenarios are modeled with OPNET Simulator. Furthermore, two case studies are conducted by choosing average queuing delay and TCP delay as performance indices respectively. In the case of HTTP protocol's performance, the changing trend with the increase of the number of clients...
This paper presents the experimental evaluation of an SDN-based orchestration system enabling the automated and coordinated arrangement of both computing and network resources in cloud Data Centers. The testbed has been set-up in the Fed4FIRE virtual experimental environment that allows for extensive, large-scale and cross-functional tests to be carried out. Results show that the selection of servers...
Geometric models are a proven aid for calculating the CapEx needed for a network deployment and used widely by telecommunication network operators for their access networks. However, for the economic viability an accurate estimation of the delivered bandwidth is important as well. In this paper a method is described to calculate a bandwidth profile for an area under investigation, given a single topology...
This paper demonstrates the physical and logical topological slicing in computer networks through Software Defined Networks (SDN) with the added benefit of data privacy. To deal with the complex requirements of the modern networks, a sudden re-configuration of a network is often required. Modern applications require the configuration of networks on a fly and according to dynamically changing requirements,...
In this paper, we study the reliable virtual network mapping (RVNM) problem for allocating virtual machines (VMs) from multiple data centers (DCs) with the objective of maximizing the total reliability of a virtual network under two capacity constraints: computing capacity constraint at each DC and bandwidth capacity constraint on each link. We first describe graph models of RVNM, formulate the RVNM...
Network visualization enables coexistence of multiple virtual networks on a shared infrastructure without requiring unified protocols, applications, and control and management planes. Recent approaches such as Software Defined Networking have enabled cloud service providers to offer virtualized network services that require embedding virtual network requests in data centers. In this paper, we employ...
Application performance data accounting for resource contention and other external influences is highly coveted and extremely difficult to obtain. "Why did my application's performance change from the last time it ran?" is a question shared by application developers, program analysts, and system administrators. The answer to this question impacts nearly all programmatic and R&D efforts...
A well-known technique for enhancing the performance and stability of content distribution is the use of multiple dissemination flows. Multipath TCP (MPTCP), the most popular multiflow protocol on the Internet, allows receivers to exploit multiple paths towards a single sender. Nevertheless, MPTCP cannot fully exploit the potential gains of multipath connectivity, as it must fairly share resources...
This paper proposes a linear formulation and an iterative heuristic, both with traffic grooming capability, which can maximize the number of remaining available routes and minimize the number of transceivers in Elastic Optical Networks (EON). The aim of the proposal is to preserve the open capacity for the accommodation of future unknown demands. Case studies are carried out in order to analyze the...
Multipath TCP is an extension to TCP protocol that allows a single connection to be split across multiple paths. MPTCP overcomes few limitations of TCP thereby offering added benefits like increased throughput and network resource utilization and resilience to possible link failures. Different data paths over the network face different end-to-end path delay. The performance of MPTCP is affected not...
Cloud-RAN (CRAN) is considered as one key en-abler for beyond 4G networks, offering multiplexing gains, and advanced cooperation and coordinated signal processing. However, a key obstacle in the adoption of the CRAN architecture is that it requires very high capacity and low latency fronthaul (FH) links to carry raw I/Q samples between remote radio heads (RRH) and the baseband units (BBUs). These...
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.