Multimedia QoS in low-cost Home Networks

This paper describes a new mechanism to garantee quality of service for multimedia streams in low-cost home networks. Quality of service is based on a token, of which the route in the network is determined by a distributed scheduler. The network node that has the token –the active node– can send its data during a predetermined period. The length of this period and which node gets the token next is calculated by the scheduler in the active node. Every node has a scheduler on-board and schedules streams according to stream information from other nodes –contained in the token– and its own streams. Although other types of scheduler could be used, the token scheduler deploys a preemptive earliest deadline first strategy. This guarantees a theoretical maximum bandwidth utilization of 100 percent. The network is simulated and a prototype is built, based on lowcost ethernet hardware. Results show a high throughput with a small overhead of less than one percent per stream.