Empirical assessment of VoIP overload detection tests

The control of communication networks critically relies on procedures capable of detecting unanticipated load changes. In this paper we explore such techniques, in a setting in which each connection consumes roughly the same amount of bandwidth (with VoIP as a leading example). We focus on large-deviations based techniques developed earlier in that monitor the number of connections present, and that issue an alarm when this number abruptly changes. The procedures proposed in are demonstrated by using real traces from an operational environment. Our experiments show that our detection procedure is capable of adequately identifying load changes

Characterization of ISP Traffic: Trends, User Habits, and Access Technology Impact

In the recent years, the research community has increased its focus on network monitoring which is seen as a key tool to understand the Internet and the Internet users. Several studies have presented a deep characterization of a particular application, or a particular network, considering the point of view of either the ISP, or the Internet user. In this paper, we take a different perspective. We focus on three European countries where we have been collecting traffic for more than a year and a half through 5 vantage points with different access technologies. This humongous amount of information allows us not only to provide precise, multiple, and quantitative measurements of "What the user do with the Internet" in each country but also to identify common/uncommon patterns and habits across different countries and nations. Considering different time scales, we start presenting the trend of application popularity; then we focus our attention to a one-month long period, and further drill into a typical daily characterization of users activity. Results depict an evolving scenario due to the consolidation of new services as Video Streaming and File Hosting and to the adoption of new P2P technologies. Despite the heterogeneity of the users, some common tendencies emerge that can be leveraged by the ISPs to improve their servic

Aktivitas Fisik dan Konsumsi Camilan pada Remaja Obesitas

Tujuan: Penelitian ini untuk mengetahui adanya perbedaan aktivitas fisik dan konsumsi camilan pada remaja obesitas di desa dan kota di Bantul.Metode: Penelitian ini menggunakan rancangan penelitian case control, dengan populasi remaja sekolah menengah atas (SMA) negeri di Kabupaten Bantul. Kasus adalah remaja yang didiagnosis obesitas pada tahap skrining, sedangkan kontrol adalah remaja dengan berat badan normal. Analisis data meliputi univariabel yang menyajikan distribusi frekuensi, bivariabel dengan uji chi-square dan uji-t dan mulitivariabel dengan uji regresi logistik.Hasil: Remaja dengan aktivitas fisik ringan memiliki peluang hampir 5 kali lebih besar mengalami obesitas dibandingkan remaja dengan aktivitas fisik sedang (OR 4,96 (CI 95%:2.14 -11.63). Hubungan antara jenis camilan dan obesitas juga memiliki hubungan yang bermakna secara statistik dan praktis, yaitu obesitas banyak di temukan sebanyak 2 kali lebih besar pada remaja dengan konsumsi camilan goreng dibandingkan dengan remaja yang mengkonsumsi camilan non goreng.Kesimpulan: Terdapat perbedaan rerata berat dan asupan camilan pada remaja obesitas dan non obesitas. Aktivitas fisik ringan, frekuensi camilan tinggi, jenis camilan gorengan, berat camilan dan asupan camilan tinggi berpeluang lebih besar meningkatkan obesitas remaja

Inside Dropbox: Understanding Personal Cloud Storage Services

Personal cloud storage services are gaining popularity. With a rush of providers to enter the market and an increasing of- fer of cheap storage space, it is to be expected that cloud storage will soon generate a high amount of Internet traffic. Very little is known about the architecture and the perfor- mance of such systems, and the workload they have to face. This understanding is essential for designing efficient cloud storage systems and predicting their impact on the network. This paper presents a characterization of Dropbox, the leading solution in personal cloud storage in our datasets. By means of passive measurements, we analyze data from four vantage points in Europe, collected during 42 consecu- tive days. Our contributions are threefold: Firstly, we are the first to study Dropbox, which we show to be the most widely-used cloud storage system, already accounting for a volume equivalent to around one third of the YouTube traffic at campus networks on some days. Secondly, we characterize the workload typical users in different environments gener- ate to the system, highlighting how this reflects on network traffic. Lastly, our results show possible performance bot- tlenecks caused by both the current system architecture and the storage protocol. This is exacerbated for users connected far from control and storage data-center

Kepentingan Indonesia Melakukan Kerjasama dengan Selandia Baru dalam Bidang Energi Geothermal

This research discusses about cooperation on New Zealand in Indonesia in in the field of geothermal energi. Indonesia is one country with the greatest potential for geothermal energi in the world. As a renewable and environmental friendly energi , geothermal energi potential need to be improved its contribution to meet domestic energi needs which will reduce Indonesias dependence on fossil energi sources dwindling. Although the potential of Indonesia has big geothermal energi , but the utilization of geothermal energi is not maximized.Indonesia decided to cooperate with New Zealand in order to maximize the utilization of geothermal energi .In this research, the writer uses library research technique. Sources were obtained from journals, website and news.Method that applied in this research is qualitative. This research also uses level of analysis of nation-state and neo-liberalism perspective. Theory of cooperationwill supports to explain the problem in this research.There are two factor behind Indonesia and New Zealand partnership. First, internal factor which geothermal resources in Indonesia has not been maximalize. This geothermal development will increase energy reserves and able to keep Indonesias energy security.Second. external factor which. New Zealand is a country with high experiences and high capabilities in geothermal development. New Zealand is also known as the state which has advantages and capabilities in geothermal technology and geothermal human resources.Keywords: cooperation, investment, energi, geothermal, interes

Network Awareness of P2P Live Streaming Applications

Early P2P-TV systems have already attracted millions of users, and many new commercial solutions are entering this market. Little information is however available about how these systems work. In this paper we present large scale sets of experiments to compare three of the most successful P2P-TV systems, namely PPLive, SopCast and TVAnts. Our goal is to assess what level of "network awareness" has been embedded in the applications, i.e., what parameters mainly drive the peer selection and data exchange. By using a general framework that can be extended to other systems and metrics, we show that all applications largely base their choices on the peer bandwidth, i.e., they prefer high-bandwidth users, which is rather intuitive. Moreover, TVAnts and PPLive exhibits also a preference to exchange data among peers in the same autonomous system the peer belongs to. However, no evidence about preference versus peers in the same subnet or that are closer to the considered peer emerges. We believe that next-generation P2P live streaming applications definitively need to improve the level of network-awareness, so to better localize the traffic in the network and thus increase their network-friendliness as wel

TCP throughput guarantee in the DiffServ Assured Forwarding service: what about the results?

Since the proposition of Quality of Service architectures by the IETF, the interaction between TCP and the QoS services has been intensively studied. This paper proposes to look forward to the results obtained in terms of TCP throughput guarantee in the DiffServ Assured Forwarding (DiffServ/AF) service and to present an overview of the different proposals to solve the problem. It has been demonstrated that the standardized IETF DiffServ conditioners such as the token bucket color marker and the time sliding window color maker were not good TCP traffic descriptors. Starting with this point, several propositions have been made and most of them presents new marking schemes in order to replace or improve the traditional token bucket color marker. The main problem is that TCP congestion control is not designed to work with the AF service. Indeed, both mechanisms are antagonists. TCP has the property to share in a fair manner the bottleneck bandwidth between flows while DiffServ network provides a level of service controllable and predictable. In this paper, we build a classification of all the propositions made during these last years and compare them. As a result, we will see that these conditioning schemes can be separated in three sets of action level and that the conditioning at the network edge level is the most accepted one. We conclude that the problem is still unsolved and that TCP, conditioned or not conditioned, remains inappropriate to the DiffServ/AF service