Showing papers by "Vassilis Prevelakis published in 2005"

The Bandwidth Exchange Architecture

Abstract: New applications for the Internet such as video on demand, grid computing etc. depend on the availability of high bandwidth connections with acceptable Quality of Service (QoS). There appears to be, therefore, a requirement for a market where bandwidth-related transactions can take place. For this market to be effective, it must be efficient for both the provider (seller) and the user (buyer) of the bandwidth. This implies that: (a) the buyer must have a wide choice of providers that operate in a competitive environment, (b) the seller must be assured that a QoS transaction will be paid by the customer, and (c) the QoS transaction establishment must have low overheads so that it may be used by individual customers without a significant burden to the provider. In order to satisfy these requirements, we propose a framework that allows customers to purchase bandwidth using an open market where providers advertise links and capacities and customers bid for these services. The model is close to that of a commodities market that offers both advance bookings (futures) and a spot market. We explore the mechanisms that can support such a model.

The bandwidth exchange architecture

Abstract: New applications for the Internet such as video on demand, grid computing etc. depend on the availability of high bandwidth connections with acceptable quality of service (QoS). There appears to be, therefore, a requirement for a market where bandwidth-related transactions can take place. For this market to be effective, it must be efficient for both the provider (seller) and the user (buyer) of the bandwidth. This implies that: (a) the buyer must have a wide choice of providers that operate in a competitive environment, (b) the seller must be assured that a QoS transaction will be paid by the customer, and (c) the QoS transaction establishment must have low overheads so that it may be used by individual customers without a significant burden to the provider. In order to satisfy these requirements, we propose a framework that allows customers to purchase bandwidth using an open market where providers advertise links and capacities and customers bid for these services. The model is close to that of a commodities market that offers both advance bookings (futures) and a spot market. We explore the mechanisms that can support such a model.

The Ethernet speaker system

Abstract: If we wish to distribute audio in a large room, building, or even a campus, we need multiple speakers. These speakers must be jointly managed and synchronized. The Ethernet Speaker (ES) system presented in this paper can be thought of as a distributed audio amplifier and speakers, it does not "play" any particular format, but rather relies on off-the-shelf audio applications (e.g., mpg123 player, Real Audio player) to act as the audio source. The Ethernet Speaker, consists of three elements: (a) a system that converts the audio output of the unmodified audio application to a network stream containing configuration and timing information (rebroad-caster), (b) the devices that generate sound from the audio stream (Ethernet Speakers), and (c) the protocol that ensures that all the speakers in a LAN play the same sounds. This paper covers all three elements, discussing design considerations, experiences from the prototype implementations, and our plans for extending the system to provide additional features such as automatic volume control, local user interfaces, and security.