We present a hierarchical multimedia archive that can serve complex multimedia requests from tertiary storage. Requests can consist of multiple request units of streamed and non-streamed data. The request units can have arbitrary synchronization patterns.

This paper presents the jukebox early quantum scheduler (JEQS). JEQS is a periodic jukebox scheduler for a Video-on-Demand system. JEQS uses the jukebox robots in a cyclic way and the time is divided in constant units called quanta. A quantum is the maximum time needed to unload and load all the drives. An RSM is loaded in a drive for a fixed period of time, corresponding to the time needed to switch the media on the other drives. During this time the drive can read data from it. JEQS is based on the scheduling theory on early quantum tasks (EQT). An early quantum task executes its first instance in the next quantum after its arrival and the rest of the instances are scheduled in a normal periodic way with the release time immediately after the first execution.

A Content Distribution Network, or CDN, is a system to improve the delivery of content to the end users (or clients) in the Internet, in which popular content may be cached or replicated at a number of servers, placed closer to some of the client populations. The design of a CDN consists of defining: (a) which content should be replicated at each server (server content), (b) the number of servers and where they should be placed in the network (server placement), (c) which server a client's requests should be sent to (server selection) and (d) how the server responses should be routed to the clients (routing). CDNs were originally designed for traditional web files (i.e., HTML, image files). However, given the increase in streaming media (i.e., video and audio) content in the Internet, the development of efficient CDN design methods that take into account the special characteristics of media objects is of great interest. These characteristics include the sustained high bandwidth requirements and the new and complex tradeoffs introduced by multicast delivery. The main goal of this thesis is to develop methods for designing streaming media CDNs with (near) minimum delivery cost, where the delivery cost includes both the server and the network bandwidth costs. We propose and evaluate a new simple minimum cost caching algorithm for

Scheduling jukebox resources is important to build efficient and flexible hierarchical storage systems. JukeTools is a toolbox that helps in the complex tasks of implementing and evaluating jukebox schedulers. It allows the fast development of jukebox schedulers. The schedulers can be tested in numerous environments, real and simulated. JukeTools helps the developer to easily detect errors in the schedules. Analyzer tools create detailed reports on the behavior and performance of any of the scheduler, and provide comparisons between different schedulers.