Network Services (network + services)

Distribution by Scientific Domains

Selected Abstracts

GSn: A new service type for integrated services on the internet,

Enrico Gregori
Network services with deterministic guarantees are based on a worst,case description of user,generated traffic. When designing a policing and scheduling algorithm for guaranteed services on the Internet, accuracy of description of the traffic profile has to be traded with simplicity of implementation. The result of this trade off is often expressed as the number of token buckets required by the service along with the choice of their parameters. The GS type of service proposed by the IETF uses two token buckets both for characterizing the traffic and for policing it. The choice of using only two token buckets is primarily driven by policing costs. In this paper we propose a method that allows the number of token buckets used for characterizing the traffic to be greater than what is actually needed to police it. This means we can obtain an accurate profile of the traffic while keeping policing simple. The method consists of computing a profile of the traffic which involves a number of token buckets of the order of ten, and then doing the policing using only the first token bucket, plus another one which is chosen depending on the delay requirements of the receivers. This paper shows that with this simple enhancement we obtain a guaranteed service whose performance closely approaches the theoretical limits of services with deterministic guarantees. [source]

TouchTone: Interactive Local Image Adjustment Using Point-and-Swipe

Chia-Kai Liang
Recent proliferation of camera phones, photo sharing and social network services has significantly changed how we process our photos. Instead of going through the traditional download-edit-share cycle using desktop editors, an increasing number of photos are taken with camera phones and published through cellular networks. The immediacy of the sharing process means that on-device image editing, if needed, should be quick and intuitive. However, due to the limited computational resources and vastly different user interaction model on small screens, most traditional local selection methods can not be directly adapted to mobile devices. To address this issue, we present TouchTone, a new method for edge-aware image adjustment using simple finger gestures. Our method enables users to select regions within the image and adjust their corresponding photographic attributes simultaneously through a simple point-and-swipe interaction. To enable fast interaction, we develop a memory- and computation-efficient algorithm which samples a collection of 1D paths from the image, computes the adjustment solution along these paths, and interpolates the solutions to entire image through bilateral filtering. Our system is intuitive to use, and can support several local editing tasks, such as brightness, contrast, and color balance adjustments, within a minute on a mobile device. [source]

The end-user application toolkit: a QoS portal for the next generation Internet

Charilaos A. Tsetsekas
Abstract The support of quality of service (QoS) in the Internet has become one of the most important topics within the Internet community. The introduction of the Integrated Services (IntServ) and the Differentiated Services (DiffServ) architectures was a major breakthrough in this direction. Enhanced by the Bandwidth Broker concept, DiffServ aims to provide QoS in the Internet through the prioritization of some IP flows over others. However, up to now the DiffServ architecture lacks a standard mechanism for the interaction between users/applications and the Bandwidth Brokers (BB), so that end-to-end QoS can be achieved. In this paper we present a distributed middleware architecture for the transparent support of QoS in the Internet. The paper focuses on bridging the gap that currently exists between applications and the network and presents the end-user application toolkit (EAT). The EAT middleware provides a framework for the presentation of network services to users, the description and selection of QoS parameters, the forwarding of reservation requests and the verification of the accredited QoS level. Through the concept of application profiles, it aims to support QoS for legacy applications, that is, commercial applications that cannot be modified to support QoS. Copyright 2003 John Wiley & Sons, Ltd. [source]

An OPNET-based simulation approach for deploying VoIP

K. Salah
These days a massive deployment of VoIP is taking place over IP networks. VoIP deployment is a challenging task for network researchers and engineers. This paper presents a detailed simulation approach for deploying VoIP successfully. The simulation uses the OPNET network simulator. Recently OPNET has gained a considerable popularity in both academia and industry, but there is no formal or known approach or methodology as to how OPNET can be used to assess the support and readiness of an existing network in deploying VoIP. Our approach and work presented in this paper predict, prior to the purchase and deployment of VoIP equipment, the number of VoIP calls that can be sustained by an existing network while satisfying QoS requirements of all network services and leaving adequate capacity for future growth. As a case study, we apply the simulation approach on a typical network of a small enterprise. The paper presents a detailed description of simulation models for network topology and elements using OPNET. The paper describes modeling and representation of background and VoIP traffic, as well as various simulation configurations. Moreover, the paper discusses many design and engineering issues pertaining to the deployment of VoIP. These issues include characteristics of VoIP traffic and QoS requirements, VoIP flow and call distribution, defining future growth capacity, and measurement and impact of background traffic.,Copyright 2006 John Wiley & Sons, Ltd. [source]

Facebook and Online Privacy: Attitudes, Behaviors, and Unintended Consequences

Bernhard Debatin
This article investigates Facebook users' awareness of privacy issues and perceived benefits and risks of utilizing Facebook. Research found that Facebook is deeply integrated in users' daily lives through specific routines and rituals. Users claimed to understand privacy issues, yet reported uploading large amounts of personal information. Risks to privacy invasion were ascribed more to others than to the self. However, users reporting privacy invasion were more likely to change privacy settings than those merely hearing about others' privacy invasions. Results suggest that this lax attitude may be based on a combination of high gratification, usage patterns, and a psychological mechanism similar to third-person effect. Safer use of social network services would thus require changes in user attitude. [source]


Judith Clifton
ABSTRACT,:,This article evaluates EU policies on public services , particularly public network services , from the citizens' point of view. It is first argued that citizens' perceptions are important because the provision of fundamental services is at stake and because they constitute the infrastructure necessary for social and economic development. Citizens',voice' can, therefore, be known, analyzed and used in the design of improved policy on public services along with other indicators. Changing EU policy on public services is synthesized and classified into two main phases in section two. Citizen satisfaction with public services as revealed through surveys from 1997 to 2007 is explored in the third section. In the discussion, the prospects for EU policy on public services are considered and, it is argued that, from the perspectives of subsidiarity and proportionality, policy towards strengthening the common market is being increasingly uploaded to the supranational level in the form of directives, whilst cohesion and redistribution policies are being downloaded to the national level or dealt with at the supranational level by ,soft' instruments. [source]

Optimal availability and security for IMS-based VoIP networks

Himanshu Pant
Consumers are continuously looking for ways of improving their productivity, simplifying their tasks, and streamlining communications both domestically and globally. This has resulted in the need to support different applications and thus the ongoing process of migrating many network services from traditional circuit-switched networks to Internet Protocol (IP) to converged networks. The circuit-switched public switched telephone network (PSTN) was a closed network where cyber-security threats were not amajor issue. With the advent of converged networks and IP-based services, service providers, government, and enterprises are concerned about the growing security threat. The new networks and equipment will be subject to many types of threats and their vulnerabilities may expose mission critical applications and infrastructure to risk. Realization of these threats can lead to service outage. Today's communications service provider must decide how to treat the effects of security breaches so as to minimize service downtime. This paper highlights amethodology, with examples to identify the effect of security-related failures and the critical design factors to be considered when modeling service reliability. The ITU-T X.805 standard (now also ISO standard 18028-2), based on the Bell Labs security model, is used to evaluate potential high impact threats and vulnerabilities. The analysis uses the Bell Labs domain technique known as security domain evaluation. One of the critical outputs provides a prioritized understanding of the threats the network is exposed to and the vulnerabilities in the security architecture. The next step in themethodology includes incorporating the threats (vulnerabilities) identified in a reliability model and quantifying the corresponding service degradation. In this paper, these concepts are applied to IP Multimedia Subsystem (IMS)-based VoIP (Voice over IP) networks. Using reliability metrics, our analysis shows that reliability models are optimistic if we do not consider security. We demonstrate how reliability models can be enhanced to take security issues into account and that the X.805 standard can be used to identify the security threats. Finally, the model shows themitigation in downtime by including intrusion-tolerance features in the product and network design. Consideration of security-caused downtimewill lead to increased focus on preventing security vulnerabilities that can lead to service outages and also allow service providers to save on maintenance costs. 2006 Lucent Technologies Inc. [source]