Broadcast program generation for Webcasting

Abstract

The advances in computer and communication technologies have made possible an ubiquitous computing environment were clients equipped with portable devices can send and receive data anytime and from anyplace. In such an asymmetric communication environment, data push has emerged as a very effective and scalable way to deliver information. Recently, the combination of push technology with the Internet and the Web [IEEE Trans. Comput. 50 (2001) 506, ACM/Kluwer Mobile Networks Appl. 7 (2002) 67] (referred to as Webcasting) has emerged ''as a way out of the Web maze''. Any broadcast program employed for Webcasting must be able to scale to the large number of transmitted pages.We study the issue of creating hierarchical Webcasting programs. We propose a new algorithm, CascadedWebcasting, for the generation of Webcasting programs, scalable in terms of the number of items transmitted and able to produce programs very close to optimal. We give an analytic model of the time complexity of the proposed method and we present a performance evaluation of CascadedWebcasting and a detailed comparison with existing algorithms using synthetic as well as real data. The experiments show that the CascadedWebcasting has negligible execution time and achieves an average access delay very close to that of the optimal algorithm.

TMBT: An Efficient Index Allocation Method for Multi-Channel Data Broadcast

“…Simply allocating data in a balanced way only reduces the average access time by a factor of the number of channels. In order to minimize average access time, skewed allocations [3,5,9,10,14] have been proposed where data are allocated according to access probabilities so that the most requested data appear in a channel with a shorter period. To solve the data allocation problem optimally, Peng and Chen [9] propose an A* approach and Yee et al [14] propose a DP (dynamic programming) approach, but these approaches are expensive.…”

Cooperative caching by clients constructing a peer-to-peer network for push-based broadcast

“…A key advantage of the push-based broadcast system is a higher throughput for data access from a huge number of clients [4,6,17,28]. The pushbased broadcast system is used for services where information with high publicity, such as movies, sounds, news, and charts is delivered to a massive number of users using satellite or terrestrial broadcasting.…”

Broadcast Data Placement over Multiple Wireless Channels

“…In the top-down (Hsu, Lee, & Chen, 2001;Yee, Navathe, Omiecinski, & Jermaine, 2002) approach, we start from a large partition, possibly including all the items, and gradually split it into smaller pieces. In the bottom-up (Hwang, Cho, & Hwang, 2001;Katsaros & Manolopoulos, 2004), we start with many small partitions which gradually grow, whereas the one-scan (Vaidya & Sohail, 1999) approach makes a single scan over the vector P = p 1 , p 2 , …, p n of the access probabilities, assigning items to channels based on some criterion. The top-down and bottom-up make multiple passes over P (or parts of it) and make splitting or concatenating decisions based on the computation of Equation 8 over P (or portions of it).…”

“…The CascadedWebcasting scheme (Casc; Katsaros & Manolopoulos, 2004) starts from a very basic intuition about the partitioning, claiming that there are three "classes" of items:…”

“…A comprehensive performance evaluation of the aforementioned algorithms has been conducted in Katsaros and Manolopoulos (2004). There, it was recognized that the greedy scheme, VF K , and DB perform very close to optimum with respect to the reduction of the average access delay, but they incur significant execution cost.…”