8,622 research outputs found
Economic Development Potential through IP Telephony for Namibia
IP telephony, economic growth, telecommunications, ICT, Granger causality, Namibia
Resource dimensioning through buffer sampling
Link dimensioning, i.e., selecting a (minimal) link capacity such that the usersâ performance requirements are met, is a crucial component of network design. It requires insight into the interrelationship between the traffic offered (in terms of the mean offered load M, but also its fluctuation around the mean, i.e., âburstinessâ), the envisioned performance level, and the capacity needed. We first derive, for different performance criteria, theoretical dimensioning formulae that estimate the required capacity C as a function of the input traffic and the performance target. For the special case of Gaussian input traffic these formulae reduce to C = M+V , where directly relates to the performance requirement (as agreed upon in a service level agreement) and V reflects the burstiness (at the timescale of interest). We also observe that Gaussianity applies for virtually all realistic scenarios; notably, already for a relatively low aggregation level the Gaussianity assumption is justified.\ud
As estimating M is relatively straightforward, the remaining open issue concerns the estimation of V . We argue that, particularly if V corresponds to small time-scales, it may be inaccurate to estimate it directly from the traffic traces. Therefore, we propose an indirect method that samples the buffer content, estimates the buffer content distribution, and âinvertsâ this to the variance. We validate the inversion through extensive numerical experiments (using a sizeable collection of traffic traces from various representative locations); the resulting estimate of V is then inserted in the dimensioning formula. These experiments show that both the inversion and the dimensioning formula are remarkably accurate
The State of Network Neutrality Regulation
The Network Neutrality (NN) debate refers to the battle over the design of a regulatory framework for preserving the Internet as a public network and open innovation platform. Fueled by concerns that broadband access service providers might abuse network management to discriminate against third party providers (e.g., content or application providers), policymakers have struggled with designing rules that would protect the Internet from unreasonable network management practices. In this article, we provide an overview of the history of the debate in the U.S. and the EU and highlight the challenges that will confront network engineers designing and operating networks as the debate continues to evolve.BMBF, 16DII111, Verbundprojekt: Weizenbaum-Institut fĂźr die vernetzte Gesellschaft - Das Deutsche Internet-Institut; Teilvorhaben: Wissenschaftszentrum Berlin fĂźr Sozialforschung (WZB)EC/H2020/679158/EU/Resolving the Tussle in the Internet: Mapping, Architecture, and Policy Making/ResolutioNe
A Survey of Bandwidth Optimization Techniques and Patterns in VoIP Services and Applications
This article surveys the various techniques adopted for optimising bandwidth
for VoIP services over the period 1999-2014. The improvement of bandwidth can
be realized through; silence suppression measure of repressing the silent
portions (packets) in a voice conversation using Voice Activity Detection
algorithm; by so doing, the transmission rate during the inactive periods of
speech is reduced, and thus, the mean transmission rate can be reduced. A
second measure is packet header reduction which defines a process of
multiplexing and de-multiplexing packet headers to curb excesses. Voice/ Packet
Header compression is considered the most productive of all the techniques,
offering a scheme where VoIP packets are compressed from the 40 bytes of size
to a smaller byte size of 2 bytes. When combined with aggregation, compression
potentially yields a compressed size of up to 1 byte. In either case, bandwidth
save is reached using compression and decompression codecs of varying data and
bit rates. It is envisaged that an improvement in the performance of codecs
would yield a better result in terms of enhancing results favourably in Voice
over broadband networksComment: 8 pages, 7 figures. ISSN (Print): 1694-0814 | ISSN (Online):
1694-078
iTeleScope: Intelligent Video Telemetry and Classification in Real-Time using Software Defined Networking
Video continues to dominate network traffic, yet operators today have poor
visibility into the number, duration, and resolutions of the video streams
traversing their domain. Current approaches are inaccurate, expensive, or
unscalable, as they rely on statistical sampling, middle-box hardware, or
packet inspection software. We present {\em iTelescope}, the first intelligent,
inexpensive, and scalable SDN-based solution for identifying and classifying
video flows in real-time. Our solution is novel in combining dynamic flow rules
with telemetry and machine learning, and is built on commodity OpenFlow
switches and open-source software. We develop a fully functional system, train
it in the lab using multiple machine learning algorithms, and validate its
performance to show over 95\% accuracy in identifying and classifying video
streams from many providers including Youtube and Netflix. Lastly, we conduct
tests to demonstrate its scalability to tens of thousands of concurrent
streams, and deploy it live on a campus network serving several hundred real
users. Our system gives unprecedented fine-grained real-time visibility of
video streaming performance to operators of enterprise and carrier networks at
very low cost.Comment: 12 pages, 16 figure
Measuring internet activity: a (selective) review of methods and metrics
Two Decades after the birth of the World Wide Web, more than two billion people around the world are Internet users. The digital landscape is littered with hints that the affordances of digital communications are being leveraged to transform life in profound and important ways. The reach and influence of digitally mediated activity grow by the day and touch upon all aspects of life, from health, education, and commerce to religion and governance. This trend demands that we seek answers to the biggest questions about how digitally mediated communication changes society and the role of different policies in helping or hindering the beneficial aspects of these changes. Yet despite the profusion of data the digital age has brought upon usâwe now have access to a flood of information about the movements, relationships, purchasing decisions, interests, and intimate thoughts of people around the worldâthe distance between the great questions of the digital age and our understanding of the impact of digital communications on society remains large. A number of ongoing policy questions have emerged that beg for better empirical data and analyses upon which to base wider and more insightful perspectives on the mechanics of social, economic, and political life online. This paper seeks to describe the conceptual and practical impediments to measuring and understanding digital activity and highlights a sample of the many efforts to fill the gap between our incomplete understanding of digital life and the formidable policy questions related to developing a vibrant and healthy Internet that serves the public interest and contributes to human wellbeing. Our primary focus is on efforts to measure Internet activity, as we believe obtaining robust, accurate data is a necessary and valuable first step that will lead us closer to answering the vitally important questions of the digital realm. Even this step is challenging: the Internet is difficult to measure and monitor, and there is no simple aggregate measure of Internet activityâno GDP, no HDI. In the following section we present a framework for assessing efforts to document digital activity. The next three sections offer a summary and description of many of the ongoing projects that document digital activity, with two final sections devoted to discussion and conclusions
- âŚ