Data communication system, data communication method, and data communication apparatus

• US 7,590,133 B2
• Filed: 02/22/1999
• Issued: 09/15/2009
• Est. Priority Date: 02/24/1998
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Niida, Mitsuo, Ohnishi, Shinji, Hatae, Shinichi, Kobayashi, Takashi
• Primary Examiner(s): HO, DUC CHI
• Application Number:
  US09/253,783
• Publication Number:
  US 20030172201A1
• Time in Patent Office: 3,858 Days
• Field of Search: 370/395.1, 370/397, 370/398, 370/399, 370/412, 370/474, 711/171
• US Class Current: 370/412
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/13 in a LAN segment, e.g. ring or bus
• CPC Class Codes: H04L 47/18 End to end
• CPC Class Codes: H04L 47/30 in combination with information about buffer occupancy at either end or at transit nodes
• CPC Class Codes: H04L 47/365 Dynamic adaptation of the packet size
• CPC Class Codes: H04L 47/43 Assembling or disassembling of packets, e.g. segmentation and reassembly [SAR]

Abstract

A data communication apparatus (a) determines a segment size and a segment data size in accordance with a size of a receiving buffer of the destination node, the size of the receiving buffer being determined by the destination node in accordance with a maximum payload size that can be received by the destination node, (b) divides object data into segments in accordance with the segment size, and (c) divides each segment into a plurality of segment data in accordance with the segment data size. The data communication apparatus (c) generates packets from the plurality of segment data, and (d) transfers the packets from the data communication apparatus to the destination node via a logical connection set between te data communication apparatus and the destination node, the logical connection being set by a controller.

Claims

1. A data communication apparatus which transfers object data to a destination nodes, said data communication apparatus comprising:

a control unit adapted (a) to determine a segment size and a segment data size in accordance with a size of a receiving buffer of the destination node, the size of the receiving buffer being determined by the destination node in accordance with a maximum payload size that can be received by the destination node, (b) to divide the object data into segments in accordance with the segment size, and (c) to divide each segment into a plurality of segment data in accordance with the segment data size; and

a data communication unit adapted (a) to generate packets from the plurality of segment data, and (b) to transfer the packets from said data communication apparatus to the destination node via a logical connection set between said data communication apparatus and the destination node, the logical connection being set by a controller.

2. A data communication apparatus according to claim 1, wherein said data communication apparatus is adapted to obtain connection information indicating the logical connection from the controller, and

wherein the packets generated by said data communication unit include the connection information.

3. A data communication apparatus according to claim 1, wherein the segment size of each segment is variable.

4. A data communication apparatus according to claim 1, wherein said data communication unit is adapted to transfer the packets via a serial bus conformed to IEEE 1394-1995 standard.

5. A data communication apparatus according to claim 1, wherein the object data includes image data.