Patent ID: 6909699
Filing Date: 2005-06-21
Classification: H04L,Y02D

Abstract:
1. A data transfer system, comprising a plurality of devices connected in a hierarchical branching arrangement including at least one intermediate device and at least one end device connected to said intermediate device, each of said devices having a different rate for transferring data and a different delay time for sending back data depending on said transfer rate, and a management apparatus for managing the transter of said data among said devices, said management apparatus including transfer rate determining means for determining a slowest transfer rate from among said transfer rates of said devices; propagation time measuring means for measuring a propagation time between said management apparatus and each of said end devices by transmitting predetermined data to each of said end devices at said slowest transfer rate; reciprocation time calculating means for calculating a maximum reciprocation time based on said measured propagation times, said maximum reciprocation time indicating the time in which said predetermined data is reciprocated for said end device farthest away from said management apparatus; and reference value calculating means for calculating a reference value based on said maximum reciprocation time, said reference value being used to calculate a waiting time required when each said device transfers said data.