Universal Multimedia Access from Wired and Wireless Systems *

Personal computing and communication devices such as computers, PDAs, and Author: Please 1. spell out PAD here mobile phones are moving to their next generation in which the end user will be able to access a multitude of information with a single device either locally or through a network. One likely trend in future personal computing and personal communication is that there will not be a single but several equivalent devices available to users allowing access to information in various forms. Each user, depending on his/her needs would access one or several among them depending on the situation and his/her preference. Using existing protocol mechanisms, in this case, a mapping and negotiation of resources during connection setup would be performed, which would remain in place throughout the life of the connection. This paper provides an overview of universal multimedia access (UMA), a concept for accessing multimedia content through a variety of possible schemes, and discusses some of the issues that arise regarding its deployment. In particular, UMA will provide a solution for adapting the delivered content when users attempt to access their choice irrespective of their terminal characteristics and communication infrastructure, as opposed to the assumption that the content remains fixed and the objective is to deliver the original content at all times. This recognition represents the impetus for the development of media descriptions and hence UMA; that is, the notion that valuable information can be derived from a variety of conversions of a multimedia content source. The issues discussed are future requirements on content servers and multimedia viewers, media conversions, UMA protocols, and UMA network architectures. The problems addressed are quality of service issues in network solutions for multimedia communications ∗ Received March 1, 2000; revised September 18, 2000. 1 Norwegian University of Science and Technology, Department of Telecommunications, 7491 Trondheim, Norway. E-mail: [email protected] 2 Signal Processing Laboratory, Swiss Federal Institute of Technology-EPFL, CH-1015 Lausanne, Switzerland. E-mail for Abdeljaoued: [email protected], E-mail for Ebrahimi: [email protected] 3 MediaLab, Ericsson Research Corporate Unit, Ericsson Radio Systems AB, 164 80 Stockholm, Sweden. E-mail: [email protected] 4 The School of Electrical, Computer and Telecommunications Engineering, University of Wollongong, Wollongong, NSW 2500, Australia. E-mail: [email protected] 388 PERKIS, ABDELJAOUED, CHRISTOPOULOS, EBRAHIMI, AND CHICHARO and reconfigurable architectures and network control based on source adaptations through media conversions and transcoding.