3,698 research outputs found
Viability approach to Hamilton-Jacobi-Moskowitz problem involving variable regulation parameters
No full textInternational audienceA few applications of the viability theory to the solution to the Hamilton-Jacobi-Moskowitz problems are presented. In the considered problem the Hamiltonian (fundamental diagram) depends on time, position and/or some regulation parameters. We study such a problem in its equivalent variational formulation. In this case, the corresponding lagrangian depends on the state of the characteristic dynamical system. As the Lax-Hopf formulae that give the solution in a semi-explicit form for an homogeneous lagrangian do not hold, a capture basin algorithm is proposed to compute the Moskowitz function as a viability solution of the Hamilton-Jacobi-Moskowitz problem with general conditions (including initial, boundary and internal conditions). We present two examples of applications to traffic regulation problems
Distributed IP mobility management for hosts and networks
No full textIncludes bibliographical references.The Internet was originally designed for stationary nodes. With the advancement of mobile nodes (such as smartphones and tablets) that have wireless Internet access capability, the original design of the Internet is no longer sufficient. These mobile nodes are capable of communicating while moving and changing their point of attachment in the Internet. To maintain communication session(s) continuity for these mobile nodes, the Internet needs mobility management mechanisms. The main mobility management protocols standardised by the Internet Engineering Task Force (IETF) are mobile IP (MIPv6 and MIPv4) and their numerous extensions and variants, including proxy MIP (PMIPv6 and PMIPv4). The architectural structures of these protocols employ a centralized mobility anchor to manage the mobility of the mobile nodes in the control and data planes. The mobility anchor manages the mobility binding information and the forwarding of data packets for all mobile nodes registered in the network. However, in the context of the rapid growth in the number of mobile users and the data traffic volume, as well as the trend towards a flat architecture in mobile networks, the centralized mobility management approach provides insufficient mobility support to the mobile nodes. For example, to manage the demand for increased mobile users, a huge amount of data traffic will be pushed to the centralized mobility anchor. Yet, routing huge volumes of traffic via the centralized mobility anchor can be non-optimal in terms of routing efficiency. Thus, the centralised mobility anchor can be a potential bottleneck, and a single point of failure. Consequently, failure of the mobility anchor may lead to a service outage for a large number of mobile nodes. Ultimately, the centralized mobility management approach does not scale well with the increase in number of mobile users and the data traffic volume. These problems are also costly to resolve within the centralized mobility management approach and its related centralized network architecture. Distributed mobility management (DMM) is one recent approach that can efficiently address the shortcomings of centralized mobility management. It provides an alternative paradigm for developing IP mobility management – without employing centralized mobility anchors. In this paradigm, either the mobility anchors, or their mobility management functions, are distributed to different networks/elements. The mobility anchors, or the mobility management functions, are brought to the edge of the networks, which is closer to the mobile nodes. Distributed mobility management also offers dynamic mobility features that allow a mobile node to anchor traffic at different mobility anchors. However, to date, mobility management schemes that have been developed based on the DMM approach are still in the preliminary stages, and there is no current standard in place. These developed DMM schemes are still experiencing problems, such as long routing paths, especially for long-lasting data traffic, a lack of route optimization for ongoing communication, and a lack of synchronization of the mobile nodes‟ location in different networks. Moreover, the majority of these proposed schemes still need to be analysed, in order to quantify their feasibility. The thesis proposes three novel network-based distributed mobility management schemes, which are based on the DMM approach. The schemes enhance PMIPv6 to work in a distributed manner, in order to address the problems of centralized mobility management. Furthermore, the schemes address the following issues: (1) the lack of route optimization for ongoing communication; (2) the lack of synchronization of the mobile nodes‟ location in different networks; and (3) the long end-to-end packet delivery delay problems in recently proposed DMM schemes. The first scheme, called the network-based distributed mobility management scheme with routing management function at the gateways (DM-RMG), decomposes the logical mobility management functions of the Local Mobility Anchor (LMA) in PMIPv6 into internetwork location management (LM), routing management (RM), and home network prefix allocation (HNP) functions. After the decomposition, the RM function is collocated at the gateways of different networks. In this way, the data-plane routing function of the respective mobile nodes is served by the corresponding local RM function at the network gateway. The DM-RMG scheme offers distributed mobility management for individual mobile nodes (i.e., mobile hosts) during mobility events. DM-RMG also implements a mechanism to optimize the handover delay. The results obtained from analytical modelling and simulation show that the DM-RMG scheme outperforms the centralized mobility management schemes, as well as currently proposed distributed mobility management schemes in terms of the end-to-end packet delivery delay under different network load conditions. The optimized handover performance of the DM-RMG scheme, investigated under different traffic patterns and mobile node speeds, shows that the scheme also mitigates the internetwork handover delay and packet loss. The second proposed scheme, called network-based distributed mobility management for the network mobility (NDM-RMG), uses a similar approach to DM-RMG. However, it proposes a network-based DMM scheme for Network Mobility (NEMO). The main goal of the NDMRMG scheme is to address the problems of centralized mobility management protocols for NEMO, including the pinball routing problem in nested NEMO. NDM-RMG is compared with centralized mobility management schemes for NEMO, and recently proposed distributed IP mobility management schemes for NEMO by means of analytical modelling and simulation evaluations. NDM-RMG shows better performance in terms of reducing the packet delivery latency, the size of the packet header, and the packet overhead experienced over the wireless link. The third proposed scheme, called network-based distributed mobility management scheme with RM and HNP allocation functions distributed to the access routers (DM-RMA), distributes the RM and the HNP allocation functions at the access routers with the mobility client function. This brings the mobility-related functions closer to the mobile nodes, that is, to the edge of the network. An analytical model is developed to investigate the mobility cost performance of the scheme, due to signalling, packet delivery, and tunnelling. The analytical results indicate that DM-RMA performs better than the previous DMM schemes in terms of packet delivery, tunnelling and total costs. Network simulator-2 (ns-2) is used to model the DM-RMA scheme. The simulated scenarios confirm that DM-RMA performs better than other proposed DMM schemes in terms of reducing the location update latency at the location managers, end-to-end packet delivery delay, handover delay, and packet loss. In addition to the three proposed DMM schemes, this thesis proposes a routing optimization scheme for PMIPv6. The main goal of this scheme is to enable PMIPv6 to offer route optimization to mobile nodes in a PMIPv6 domain. The scheme reduces the route optimization-establishment latency, the packet delivery latency, and the packet loss. Using ns-2 simulations and considering different simulated scenarios, the results show that the scheme reduces route optimization-establishment latency and delayed packets during the route optimization operation, as compared to previously proposed PMIPv6 route optimization schemes. The results also show that the scheme reduces packet loss when a mobile node undergoes handover in the PMIPv6 domain
IMS: The New Generation of Internet-Protocol-Based Multimedia Services
No full textLegacy networks, both fixed and mobile, which were originally designed for voice communications, are progressively migrating to new infrastructures that promise to revolutionize the services offered. In this paper, we will cover this new generation of personal communication services, with an emphasis on the family of Internet protocol (IP)-based multimedia subsystem (IMS)-aided infrastructure that relies on the session initiation protocol (SIP). As a benefit, the end users will enjoy a new generation of personal communications services that are accessible anywhere and anytime. These services are timedia subsystem (IMS)-aided infrastructure that relies on the directly related to the end users rather than to their diverse devices. It is anticipated that the new deployments of next-of the IMS technology. generation networks (all-IP based) will accelerate the adoptio
Perceptions of intellectual property: a review
No full textIn “The right to good ideas: patents and the poor”, The Economist depicts two driving forces in the contemporary discourse on IP and globalization. The one is interested in advancing the knowledge economy, an approach based on the belief that knowledge is the driving factor behind economic growth. The other resides on a belief that IP is a major means to advance the process of globalization. While the former is strongly motivated by new economic growth theory, as for example advanced by Stanford professor Paul Romer, the latter is based on typical anti-globalization arguments, such as for example the position that the IP system helps multinational companies to build up monopolies to the detriment of the poor, drives small and medium-sized enterprises (SMEs) and local business in developing countries out of business and increases prices for consumer products, be they pharmaceuticals or software. The purpose of this review is to help understand the current discourse on intellectual property, to grasp underlying themes, assumptions and connotations associated with the term “IP”, so as to identify paths leading to a more comprehensive understanding of IP and the opportunities and pitfalls it may provide
Author Correction: Identifying genetic factors that contribute to the increased risk of congenital heart defects in infants with Down syndrome (Scientific Reports, (2020), 10, 1, (18051), 10.1038/s41598-020-74650-4)
No full text\ua9 2021, The Author(s).Ivan P. Moskowitz was omitted from the author list in the original version of this Article
Efficient Learning of Communication Profiles from IP Flow Records
No full textThe task of network traffic monitoring has evolved drastically with the ever-increasing amount of data flowing in large scale networks. The automated analysis of this tremendous source of information often comes with using simpler models on aggregated data (e.g. IP flow records) due to time and space constraints. A step towards utilizing IP flow records more effectively are stream learning techniques. We propose a method to collect a limited yet relevant amount of data in order to learn a class of complex models, finite state machines, in real-time. These machines are used as communication profiles to fingerprint, identify or classify hosts and services and offer high detection rates while requiring less training data and thus being faster to compute than simple models.Accepted author manuscriptCyber Securit
Scalable QoS-aware Mobility for Future Mobile Operators
No full textTelecom operators and Internet service providers
are heading for a new shift in communications
paradigms. The forthcoming convergence
of cellular and wireless data networks is often
manifested in an “all IP approach” in which all
communications are based on an end-to-end IP
protocol framework. The approach to network
design becomes user and service-centered, so
that continuous reachability of mobile users and
sustained communication capabilities are default
requirements for a prospective architecture. In
this article, we describe a network architecture
which is able to provide seamless communication
mobility, triggered either by the user or by the
network, across multiple technologies. The architecture
allows for media independent handovers
and supports optimized mobility and resource
management functions. The main focus of the
article is on major technical highlights of mobility
and quality-of-service (QoS) management subsystems
for converged networks.Publicad
Malicious IP Address Prediction
No full textabstract: IP blacklisting is a popular technique to bolster an enterprise's security, where access to and from designated IP addresses is explicitly restricted. The fundamental idea behind blacklists is to continually add IP addresses that reputable entities, such as security researchers, have labeled as malicious to the list. Currently IP blacklisting is a reactive method, where malicious IP addresses are identified after their engagement in malicious activities is detected (e.g. hosting malware samples or sending spam emails). This thesis project aims to address this issue, by laying the groundwork for a machine learning tool that proactively identifies malicious IP address. The ground truth data derives from VirusTotal, a company that synthesizes security knowledge from prominent sources, such as Symantec, Fortinet, and ESET. I passed 307,621 IP addresses found in posts on the D2web (deep and dark web) through VirusTotal. If at least one detected URL associates with the IP address and VirusTotal deems it positive, I accordingly label the IP address as positive (malicious), and negative (non-malicious) otherwise. To give some insight into the ground truth, 6,147 IP addresses were identified as positive from the original 307,621. Furthermore, in order to quantify the prediction capabilities of our models, I introduce a metric called lead time. Lead time represents the difference between the date an IP address was first seen on the D2web and its earliest date on VirusTotal. For example, if an IP address was mentioned on the D2web on 1/5/2017 and mentioned on VirusTotal on 1/25/2017, then its lead time is 20 days. After feature selection, where I handpicked features from the data mined from the D2web, I attempted various combinations of classifiers and feature sets in order to create the best model. The final machine learning models implement temporal cross validation - where I train a model on data from 1/1/2016 up until a testing month in 2017, and test on data from the testing month - with a Random Forest classifier. The following are results from a model that was tested on January 2017, which exhibits median performance among the final models. The true positive rate is 0.2558, the false positive rate is 0.3612, and the average lead time (for leading true positives) is 193 days, where the model picks up 33.33% of all leading true positives. Although the model finds a respectable number of true positives, it picks up too many false positives. Thus, my approach is ineffective at predicting malicious IP addresses in their current state, meaning additional efforts will be required to transform the current work into a viable too
The Usage of MPLS in Voice over IP Network
No full textAbstract: The article focused on the usage of Multiprotocol Label Switching (MPLS) over VOIP network. One of the features that MPLS has is Traffic Engineering (TE) which can help overcome potential pot holes in the network or to circumvent sub-optimal paths, especially in a network consisting of a diverse geographical terrain. The prevalence of MPLS IP VPN networks make them the de facto transport for inter-connecting IMS based VoIP devices. Inevitably, this creates the need for a fundamental set of guidelines, which can ensure that the quality of service for real time traffic is acceptable. To that end, a systematic approach was taken to implement traffic engineering LSPs which enabled the real time multimedia traffic to be delivered with highest priority and minimal loss and delay. This helped provide tangible network operations benefits such as, early detection of service disruption because of faults in the desired end to end label switched paths, reduction of the Mean Time to Resolve (MTTR) and lead to proposals for further improvements which could produce a more intelligent re-routing of the LSPs
Keywords: Multiprotocol Label Switching (MPLS), Traffic Engineering (TE), Voice over Internet Protocol (VoIP), Internet Protocol (IP), Label Switched Path (LSP).
Title: The Usage of MPLS in Voice over IP Network
Author: Kashif R. Khawaja, Hulaiyel M. Khaldi, Majed I. Shukri, Baraka H. Mutairi, Fahad Nasser Al-Khaldi
International Journal of Engineering Research and Reviews
ISSN 2348-697X (Online)
Vol. 10, Issue 3, July 2022 - September 2022
Page No: 6-10
Research Publish Journals
Website: www.researchpublish.com
Published Date: 12-August-2022
DOI: https://doi.org/10.5281/zenodo.6985144
Paper Download Link (Source)
https://www.researchpublish.com/papers/the-usage-of-mpls-in-voice-over-ip-networkInternational Journal of Engineering Research and Reviews, ISSN 2348-697X (Online), Research Publish Journals, Website: www.researchpublish.co
Design and Experimental Evaluation of a Route Optimisation Solution for NEMO
No full textAn important requirement for Internet protocol (IP)
networks to achieve the aim of ubiquitous connectivity is network
mobility (NEMO). With NEMO support we can provide Internet
access from mobile platforms, such as public transportation vehicles,
to normal nodes that do not need to implement any special
mobility protocol. The NEMO basic support protocol has been
proposed in the IETF as a first solution to this problem, but this
solution has severe performance limitations. This paper presents
MIRON: Mobile IPv6 route optimization for NEMO, an approach
to the problem of NEMO support that overcomes the limitations
of the basic solution by combining two different modes of operation:
a Proxy-MR and an address delegation with built-in routing
mechanisms. This paper describes the design and rationale of the
solution, with an experimental validation and performance evaluation
based on an implementation.Publicad
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