att_abstract={{Interactivity is promised by IP-based content distribution, particularly with IPTV. We investigate the user viewing activity for broadcast TV, pre-recorded content using Digital Video Recording (DVR) and video on demand (VoD). Advanced stream control functions (play, pause, skip, rewind, etc.) provide users  with a high level of interactivity, but place demands on the distribution  infrastructure (servers, network, home-network) that can be difficult to  manage at large scale. To support system design as well as network  capacity planning, it is necessary to have a good model of user  interaction. Using traces from a well-provisioned operational environment  with a large user population, we first characterize interactivity for  broadcast TV, DVR and VoD. We then develop parametric models of individual  users stream control operations for VoD. Our analysis shows that  interactive behavior is adequately characterized by two semi-Markov  models, one for weekdays and another for weekends. We propose a parametric  model for the underlying sojourn time distributions and show that it  results in a superior fit compared to well known distributions  (generalized Pareto and Weibull). In order to validate that our models  faithfully capture user behavior, we compare the workload that a VoD  server experiences in response to actual traces and synthetic data  generated from our proposed models. }},
	att_authors={vg7777, rj2124, rk1931, kr2812, ds1693, vv9482},
	author={Vijay Gopalakrishnan and Rittwik Jana and Ralph Knag and Kadangode Ramakrishnan and Deborah Swayne and Vinay Vaishampayan},
	institution={{IEEE Infocom 2010}},
	title={{Characterizing Interactive Behavior in a Large-Scale Operational IPTV Environment}},