Patent ID: 8559424
Filing Date: 2013-10-15
Classification: H04L

Abstract:
1. A data communication method in a network including a plurality of communication apparatuses connected in the form of a ring, the method comprising: calculating transmission time between a sending apparatus and a granting apparatus, which grants control of a bus to the sending apparatus, in each of a first communication environment in which data is transferred in a first direction on the network by disabling a first port circuit of the granting apparatus for transferring the data in a second direction and a second communication environment in which data is transferred in the second direction by disabling a second port circuit of the granting apparatus for transferring the data in the first direction, the second direction being different from the first direction; and changing a transfer direction on the network based on the calculated transmission times so that a time interval between a transmission of the data from the sending apparatus to a reception of the data at a destination communication apparatus is minimized, wherein, in the calculating transmission time, the granting apparatus sends a packet to the sending apparatus in each of the first and second communication environments and measures a time between the sending of the packet and the arrival of a response packet to calculate the transmission time in each of the first and second communication environments.