Showing papers by "Marco Furini published in 2000"

Real-Time Traffic Transmission over the Internet

Abstract: Multimedia applications require the transmission of real-time streams over a network. These streams often exhibit variable bandwidth requirements, and require high bandwidth and guarantees from the network. This creates problems when such streams are delivered over the Internet. To solve these problems, recently, a small set of differentiated services has been introduced. Among these, Premium Service is suitable for real-time transmissions. It uses a bandwidth allocation mechanism (BAM) based on the traffic peak rate. Since the bandwidth requirement of a video stream can be quite variable, this can result in a high cost to the user and an inefficient use of network bandwidth. In this paper we introduce a BAM that can increase bandwidth utilization and decrease the allocated bandwidth without affecting the QoS of the delivered real-time stream and without introducing any modification in the Premium Service. We also introduce several frame dropping mechanisms that further reduce bandwidth consumption subject to a QoS constraint when coupled with the above BAM. The proposed BAM and the heuristics algorithms are evaluated using Motion JPEG and MPEG videos and are shown to be effective in reducing bandwidth requirements.

Real-Time Trac Transmission over the Internet

Abstract: Multimedia applications require the transmission of real- time streams over a network. These streams often exhibit variable band- width requirements, and require high bandwidth and guarantees from the network. This creates problems when such streams are delivered over the Internet. To solve these problems, recently, a small set of dierentiated services has been introduced. Among these, Premium Service is suitable for real-time transmissions. It uses a bandwidth allocation mechanism (BAM) based on the trac peak rate. Since the bandwidth requirement of a video stream can be quite variable, this can result in a high cost to the user and an inecient use of network bandwidth. In this paper we introduce a BAM that can increase bandwidth utilization and decrease the allocated bandwidth without aecting the QoS of the delivered real- time stream and without introducing any modication in the Premium Service. We also introduce several frame dropping mechanisms that fur- ther reduce bandwidth consumption subject to a QoS constraint when coupled with the above BAM. The proposed BAM and the heuristics algorithms are evaluated using Motion JPEG and MPEG videos and are shown to be eective in reducing bandwidth requirements.

Design and analysis of RT-Ring: a protocol for supporting real-time communications

Abstract: Real-time applications, such as process control signals and multimedia transmission, are being increasingly deployed in networks. These applications produce a type of traffic with stringent timing requirements whose transmission is critical as it has to be completed within its deadline. This can be performed only using protocols that support real-time traffic transmission. We propose a new real-time protocol, called RT-Ring, able to support transmission of both real-time and generic traffic over a ring network. RT-Ring provides both network guarantees and high network resource utilization, while ensuring compatibility with the emerging differentiated service architecture. Network guarantees are fully proved and high network utilization is highlighted by a comparison study with the FDDI protocol. This comparison shows that RT-Ring network capacities are greater than the corresponding FDDI capacities.