Cooperative Buffering Schemes for Time-Shifted Live Streaming of Distributed Appliances

Distributed appliances connected to the Internet have provided various multimedia services. In particular, networked Personal Video Recorders (PVRs) can store broadcast TV programs in their storage devices or receive them from central servers, enabling people to watch the programs they want at any desired time. However, the conventional CDNs capable of supporting a large number of concurrent users have limitations in scalability because more servers are required in proportion to the increased users. To address this problem, we have developed a time-shifted live streaming system over P2P networks so that PVRs can share TV programs with each other. We propose cooperative buffering schemes to provide the streaming services for time-shifted periods even when the number of PVRs playing back at the periods is not sufficient; we do so by utilizing the idle resources of the PVRs playing at the live broadcast time. To determine which chunks to be buffered, they consider the degree of deficiency and proximity and the ratio of playback requests to chunk copies. Through extensive simulations, we show that our proposed buffering schemes can significantly extend the time-shifting hours and compare the performance of two buffering schemes in terms of playback continuity and startup delay.

Modified Startup Delay Providing Circuit for Integrated Circuits

<p>Power management in integrated circuits is critical and some ICs require voltages to be applied in a particular sequence. Integrated circuits consist of various distinct sub-circuits and power delivery to each of those circuits at the proper time is required for proper operation. Some examples are Subscriber line interface circuit (SLIC), switching voltage regulators, etc. Thus, startup delay circuits are necessary as they ensure the delivery of power to circuits at the appropriate time. Time delays are conventionally generated by resistor-capacitor pair but the time constant is very small, for higher time delay, we have to increase resistor-capacitor sizes which require more space and is not economical. In this paper, a new technique is proposed for the generation of sufficient time delays eliminating the need for larger resistor and capacitor combination. The proposed startup delay circuit is designed in 180 nm. CMOS process and simulated in LTSpice.</p>

Modified Startup Delay Providing Circuit for Integrated Circuits

<p>Power management in integrated circuits is critical and some ICs require voltages to be applied in a particular sequence. Integrated circuits consist of various distinct sub-circuits and power delivery to each of those circuits at the proper time is required for proper operation. Some examples are Subscriber line interface circuit (SLIC), switching voltage regulators, etc. Thus, startup delay circuits are necessary as they ensure the delivery of power to circuits at the appropriate time. Time delays are conventionally generated by resistor-capacitor pair but the time constant is very small, for higher time delay, we have to increase resistor-capacitor sizes which require more space and is not economical. In this paper, a new technique is proposed for the generation of sufficient time delays eliminating the need for larger resistor and capacitor combination. The proposed startup delay circuit is designed in 180 nm. CMOS process and simulated in LTSpice.</p>

Inferring Streaming Video Quality from Encrypted Traffic

Inferring the quality of streaming video applications is important for Internet service providers, but the fact that most video streams are encrypted makes it difficult to do so.We develop models that infer quality metrics (i.e., startup delay and resolution) for encrypted streaming video services. Our paper builds on previous work, but extends it in several ways. First, the models work in deployment settings where the video sessions and segments must be identified from a mix of traffic and the time precision of the collected traffic statistics is more coarse (e.g., due to aggregation). Second, we develop a single composite model that works for a range of different services (i.e., Netflix, YouTube, Amazon, and Twitch), as opposed to just a single service. Third, unlike many previous models, our models perform predictions at finer granularity (e.g., the precise startup delay instead of just detecting short versus long delays) allowing to draw better conclusions on the ongoing streaming quality. Fourth, we demonstrate the models are practical through a 16-month deployment in 66 homes and provide new insights about the relationships between Internet "speed" and the quality of the corresponding video streams, for a variety of services; we find that higher speeds provide only minimal improvements to startup delay and resolution.

Central-Evaluation Neighbors Acquiring Method for P2P Streaming System

To solve the high startup delay and playback delay in P2P streaming system which are caused by peers randomly join or leave the network, we proposed a neighbors acquiring method. This paper presents the details of our neighbors acquiring method. We use tracker server to grasp the information of all nodes in the P2P network. Based on these information, tracker server could pass proper neighbor nodes to the peer node which request neighbors from tracker server through evaluation process. Some conditions are involved in the evaluation process, like node activeness, bandwidth, time nodes existing, buffer-map matching. We estimate our neighbors acquiring method through a P2P streaming system simulation. The simulation results show the P2P streaming system which uses our neighbors acquiring method has lower startup delay and playback delay than the P2P streaming system which uses random neighbors acquiring method.

Effects of Countdown Signals in Red Phase on Drivers: A Comparative Study between Japan and Turkey

Countdown signals can be found in many countries; however, there are only a few researches that study the impact of the signals on driver behavior. In this study, we focus particularly on the behavior of drivers reacting to countdown signals when the signal shifted from red to green. Although the countdown signal can reduce startup delay, it also causes drivers premature start. This paper determines the factors influencing the behaviors of drivers on startup delay, premature start, and headway due to countdown signals. The analysis results are compared between Japan and Turkey. From our findings, we propose countermeasures to reduce the problems caused by the countdown signals which can be a guideline for implementation or modification of countdown-signalized intersections in many countries in order to increase safety of both drivers and pedestrians as well as drivers’ satisfactions.