Broadcast disks

Abstract

This paper proposes the use of repetitive broadcast as a way of augmenting~he memory hierarchy of clients in an asyrnmdric communication environment.We describe a new technique called "Broadcast Disks" for structuring the broadcast in a way that provides improved performance for non-unformly accessed data.The Broadcast Disk superimposes multiple disks spinning at different speeds on a single broadcast channel-in e~ect creating an arbitrarily fine-grainedmemory hierarchy. In addition to proposing and defining the mechanism, a main result of this work is that exploiting the potential of the broadcast structure requires a reevaluation of basic cache managementpolicies.We examine several "pure" cache management policies and develop and measure implementable approximations to these policies. These results and others arepresented in a set of simulation studies that substantiates the basic idea and develops some of the intuitions required to design a particular broadcast program.

On-demand data broadcast with deadlines for avoiding conflicts in wireless networks

“…First, in the research on push-based data broadcast, Acharya et al (1995) proposed the first algorithm to achieve the pre-selected data items placed at a single channel, and disseminated the pre-selected data items on the basis of access probability. Consequently, due to the parallelism of multiple channels, Vaidya and Hameed (1999) proposed several algorithms to determine data scheduling pattern that minimizes the waiting time of client in multiple channels.…”

Generalizing the Square Root Rule for Optimal Periodic Scheduling in Push-Based Wireless Environments

“…Heuristic, low complexity scheduling methods were introduced in [2] with the introduction of the Broadcast Disks model. According to it, items are grouped by popularity, forming virtual disks rotating around a common axis.…”

“…In accordance with the related work on scheduling [2], [3], [4], [5], [7], [10], [11], [12], [13], [15], [16], [17], [18], [19], [20], an item is simply a piece of information that a client may acquire through a single query. It is clarified that in pushbased broadcast scheduling, the term "client query" does not imply posting a request to a server, but rather waiting for the broadcast of a specific item.…”

“…This approximation, stemming from the schedule size infinity assumption ( ! 1), is traditionally employed in related studies [2], [3], [4], [5], [7], [10], [11], [12], [13], [15], [16], [17].…”

“…Additionally, proper transmission scheduling ensures optimal Quality of Service. Periodic scheduling [2] is typically employed in Teletext, TV, and Radio (e.g., DVB-H/T, DAB) broadcasting. A fundamental pursuit in periodic scheduling has been the creation of an infinite schedule than minimizes the mean serving time of the clients [3].…”