Data communication method and communication apparatus
AssigneeFujitsu Semiconductor Limited
InventorHitoshi Ogawa
Life of this patent
Estimating the term…
Abstract
A data communication method in a network including a plurality of communication apparatuses connected in the form of a ring, the network being logically broken at a given position, the method comprising: calculating transmission time between a sending apparatus and a granting apparatus granting 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 and a second communication environment in which data is transferred in a second direction different from the first direction; and changing the transfer direction on the network for each sending apparatus to a transfer direction that provides shorter transmission time on the basis of the calculated transmission times and performing data transfer.
Claims13
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.
A data communication method in a network including a plurality of communication apparatuses connected in the form of a ring, the method comprising:
- calculating a number of repeats during data transfer 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 where 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 where 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, the number of repeats repeating a packet in the each of the plurality of communication apparatuses;
- and
- changing the transfer direction on the network based on the calculated numbers of repeats for minimizing the number of repeats.
A communication apparatus acting as a granting apparatus on a network including a plurality of communication apparatuses connected in the form of a ring, the communication apparatus comprising:
- a calculator configured to calculate one of transmission time and a number of repeat transmission between a sending apparatuses and a granting apparatus, which grants control of a bus to the sending apparatus, in each of a first communication environment where 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 where 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 on the network;
- and
- a switch configured to change the transfer direction on the network based on the calculated transmission times so that one of a transmission time and a number of repeat transmission for the sending apparatus is minimized,
- wherein the calculator sends a packet for measuring transmission time to the sending apparatus in the first and second communication environments and measures the time between the sending of the packet and the arrival of a response packet in response to the packet at the granting apparatus to calculate the transmission time in each of the first and second communication environments.
Dependencies are inferred from the claim text.