Marvin Sirbu

Professor – EPP, ECE

Department	Electrical and Computer Engineering
Office	129K Baker Hall
Telephone	(412)-268-3436
Fax	(412)-268-3757
Email	sirbu@cmu.edu

Research Interests

Telecommunications Convergence

Telecommunications networks have histori-cally been optimized for voice traffic. Over the next decade, the world's networks will be dominated by data traffic, and voice will be carried as just one more type of data on integrated service packet networks. We are exploring the impacts of this convergence on telecommunications regulation and competition. More specifically, we are developing engineering economic models to alternative network architectures to examine issues of comparative economics, economies of scale and scope, and the impact of regulatory policies governing competitive entry, unbundling, interconnection and universal service. Particular attention is being focused on voice over internet protocol (VoIP) and its impact on local exchange competition, and the regulatory treatment of telecommunications and information services. Practical experience in operating VoIP systems is being gained through an instrumented testbed.

Network Economics

On a gigabit network, if service is priced per bit sent, then either voice is effectively free or video is unaffordable. Flat-rate access leads to casual users subsidizing intensive users. Professor Sirbu is developing formal models for network supply and demand that can lead to efficient and practical pricing structures.