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It is often argued that rapidly increasing video content along with the penetration of high-speed access is leading to explosive growth in the Internet traffic. Contrary to this popular claim, technically solid reports show only modest traffic growth worldwide. This paper sheds light on the causes of the apparently slow growth trends by analyzing commercial residential traffic in Japan where the fiber access rate is much higher than other countries. We first report that Japanese residential traffic also has modest growth rates using aggregated measurements from six ISPs. Then, we investigate residential per-customer traffic in one ISP by comparing traffic in 2005 and 2008, before and after the advent of YouTube and other similar services. Although at first glance a small segment of peer-to-peer users still dictate the overall volume, they are slightly decreasing in population and volume share. Meanwhile, the rest of the users are steadily moving towards rich media content with increased diversity. Surely, a huge amount of online data and abundant headroom in access capacity can conceivably lead to a massive traffic growth at some point in the future. The observed trends, however, suggest that video content is unlikely to disastrously overflow the Internet, at least not anytime soon.

It has been reported worldwide that peer-to-peer traffic is taking up a significant portion of backbone networks. In particular, it is prominent in Japan because of the high penetration rate of fiber-based broadband access. In this paper, we first report aggregated traffic measurements collected over 21 months from seven ISPs covering 42% of the Japanese backbone traffic. The backbone is dominated by symmetric residential traffic which increased 37%in 2005. We further investigate residential per-customer trafficc in one of the ISPs by comparing DSL and fiber users, heavy-hitters and normal users, and geographic traffic matrices. The results reveal that a small segment of users dictate the overall behavior; 4% of heavy-hitters account for 75% of the inbound volume, and the fiber users account for 86%of the inbound volume. About 63%of the total residential volume is user-to-user traffic. The dominant applications exhibit poor locality and communicate with a wide range and number of peers. The distribution of heavy-hitters is heavy-tailed without a clear boundary between heavy-hitters and normal users, which suggests that users start playing with peer-to-peer applications, become heavy-hitters, and eventually shift from DSL to fiber. We provide conclusive empirical evidence from a large and diverse set of commercial backbone data that the emergence of new attractive applications has drastically affected traffic usage and capacity engineering requirements.

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This paper investigates the effects of the rapidly-growing residential broadband traffic on commercial ISP backbone networks. We collected month-long aggregated traffic logs for different traffic groups from seven major ISPs in Japan in order to analyze the macro-level impact of residential broadband traffic. These traffic groups are carefully selected to be summable, and not to count the same traffic multiple times.Our results show that (1) the aggregated residential broadband customer traffic in our data exceeds 100Gbps on average. Our data is considered to cover 41% of the total customer traffic in Japan, thus we can estimate that the total residential broadband traffic in Japan is currently about 250Gbps in total. (2) About 70% of the residential broadband traffic is constant all the time. The rest of the traffic has a daily fluctuation pattern with the peak in the evening hours. The behavior of residential broadband traffic deviates considerably from academic or office traffic. (3) The total traffic volume of the residential users is much higher than that of office users, so backbone traffic is dominated by the behavior of the residential user traffic. (4) The traffic volume exchanged through domestic private peering is comparable with the volume exchanged through the major IXes. (5) Within external traffic of ISPs, international traffic is about 23% for inbound and about 17% for outbound. (6) The distribution of the regional broadband traffic is roughly proportional to the regional population.We expect other countries will experience similar traffic patterns as residential broadband access becomes widespread.

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This paper presents our field experience in data collection from remote sensors. By letting tractors, farmers, and sensors have short-range radio communication devices with delay-disruption tolerant networking (DTN), we can collect data from those sensors to our central database. Although, several implementations have been made with cellular phones or mesh networks in the past, DTN-based systems for such applications are still under explored. The main objective of this paper is to present our practical implementation and experiences in DTN-based data collection from remote sensors. The software, which we have developed for this research, has about 50 kbyte footprint, which is much smaller than any other DTN implementation. We carried out an experiment with 39 DTN nodes at the University of Tokyo assuming an agricultural scenario. They achieved 99.8% success rate for data gathering with moderate latency, showing sufficient usefulness in data granularity.Index Terms-Delay-disruption tolerant networking (DTN), experiment, sensor data gathering, sensor networks.