Data communication apparatus and data communication method

• US 20030093461A1
• Filed: 05/03/2002
• Published: 05/15/2003
• Est. Priority Date: 11/15/2001
• Status: Active Grant

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Suzuki, Yasuhiro, Yoshida, Hiroshi
• Granted Patent: US 7,051,100 B2
• Time in Patent Office: Days
• US Class Current: 709/202
• CPC Class Codes: G06F 16/9574 of access to content, e.g. by caching
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/612 for unicast
• CPC Class Codes: H04L 67/561 Adding application-functional data or data for application control, e.g. adding metadata
• CPC Class Codes: H04L 67/564 Enhancement of application control based on intercepted application data
• CPC Class Codes: H04L 67/565 Conversion or adaptation of application format or content adding application control or application functional data H04L67/561
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04N 21/23106 involving caching operations prefetching while addressing of a memory level in which the access to the desired data or data block requires associative addressing means within memory systems or architectures G06F12/0862; caching at an intermediate stage in a data network H04L67/568

Abstract

The present invention aims to perform streaming delivery with compensating missing data when a part of the streaming data of the streaming delivery is missing. On receiving a delivery request to a media server from a client, a cache checking unit checks if the streaming data to be delivered is stored in a cache data storing unit. If not stored, the cache checking unit sends the delivery request to the media server, and a streaming data caching unit receives the streaming data delivered from the media server and judges an existence of missing data within the delivered streaming data. If exists, a missing data requesting unit sends a delivery request for the missing data to the media server, and a streaming data delivering unit performs the streaming delivery of the streaming data and the missing data received from the media server to the client.

Claims

1. A data communication apparatus for performing communication between a terminal device requesting streaming delivery of a piece of information data and a delivering apparatus holding at least one piece of information data and performing the streaming delivery of the information data requested by the terminal device, the data communication apparatus comprising:

a data storing unit available to store any piece of the information data;

a delivery request receiving unit for receiving a delivery request of the streaming delivery of specific information data from the terminal device;

a data checking unit for checking if requested information data of which the streaming delivery is requested by the delivery request is stored in the data storing unit, and sending the delivery request to the delivering apparatus if the requested information data is not stored in the data storing unit;

a data receiving unit for receiving delivered requested information data which is the requested information data delivered from the delivering apparatus, and judging an existence of missing data within the delivered requested information data;

a data delivering unit for performing the streaming delivery of the delivered requested information data received by the data receiving unit to the terminal device; and

a missing data notifying unit for sending a missing data notice for informing of the missing data within the delivered requested information data, when the missing data is detected within the delivered requested information data by the data receiving unit.

6. The data communication apparatus of claim 1 or 2,

wherein, when the delivered requested information data is stored in the data storing unit, the data delivering unit performs the streaming delivery of the delivered requested information data stored in the data storing unit to the terminal device.

17. The data communication apparatus of one of claims 1, 2, and 9, wherein

before the data storing unit finishes storing the delivered requested information data, the delivery request receiving unit receives the delivery request of the delivered requested information data from a new terminal device other than the terminal device, and then the data storing unit finishes storing the delivered requested information data without storing a part of the delivered requested information data,

the data delivering unit performs the streaming delivery of the delivered requested information data except an unstored part which has not been stored in the data storing unit to the new terminal device,

the data checking unit sends an unstored part delivery request for requesting the streaming delivery of the unstored part to the delivering apparatus,

the data receiving unit receives the unstored part delivered from the delivering apparatus, and

the data delivering unit performs the streaming delivery of the unstored part received by the data receiving unit to the new terminal device.

2. A data communication apparatus performing communication between a terminal device requesting streaming delivery of a piece of information and a delivering apparatus holding at least one piece of information data and performing the streaming delivery of the information data requested by the terminal device, the data communication apparatus comprising:

a data storing unit available to store any piece of the information data;

a delivery request receiving unit for receiving a delivery request of the streaming delivery of specific information data from the terminal device;

a data checking unit for checking if requested information data of which the streaming delivery is requested by the delivery request is stored in the data storing unit, and sending the delivery request to the delivering apparatus if the requested information data is not stored in the data storing unit;

a data receiving unit for receiving delivered requested information data which is the requested information data delivered from the delivering apparatus, and judging an existence of missing data within the delivered requested information data;

a data delivering unit for performing the streaming delivery of the delivered requested information data received by the data receiving unit to the terminal device;

a missing data transmission requesting unit for sending a missing data transmission request to the delivering apparatus for requesting a transmission of the missing data within the delivered requested information data, when the missing data is detected within the delivered requested information data by the data receiving unit; and

a missing data receiving unit for receiving the missing data from the delivering apparatus, and

wherein the data storing unit stores the delivered requested information data received by the data receiving unit, and stores the missing data received by the missing data receiving unit with relating the missing data to the delivered requested information data.

3. The data communication apparatus of claim 2,

wherein the data receiving unit receives the delivered requested information data with judging an existence of the missing data, and

wherein the missing data transmission requesting unit sends the missing data transmission request to the delivering apparatus at a time when the data receiving unit detects the missing data within the delivered requested information data.

4. The data communication apparatus of claim 2,

wherein the data receiving unit receives the delivered requested information data with judging an existence of the missing data, stores the delivered requested information data in the data storing unit in an order of receiving the delivered requested information data, and suspends a process of storing the delivery requested data in the data storing unit at a time when the missing data is detected within the delivered requested information data, and restarts the process of storing the delivery requested data in the data storing unit after the missing data has been stored in the data storing unit.

5. The data communication apparatus of claim 2,

wherein when the missing data is detected by the data receiving unit, the missing data transmission requesting unit sends the missing data transmission request to the delivering apparatus after the data storing unit has stored the delivered requested information data.

7. A data communication apparatus for performing communication between a terminal device requesting streaming delivery of a piece of information and a delivering apparatus holding at least one piece of information data and performing the streaming delivery of the information data requested by the terminal device, the data communication apparatus comprising:

a data storing unit available to store any piece of the information data;

a delivery request receiving unit for receiving a delivery request of the streaming delivery of specific information data from the terminal device;

a data checking unit for checking if requested information data of which the streaming delivery is requested by the delivery request is stored in the data storing unit;

a missing data judging unit for judging an existence of missing data within the requested information data stored when the requested information data is stored in the data storing unit;

a missing data transmission requesting unit for sending a missing data transmission request to the delivering apparatus for requesting transmission of the missing data within the stored requested information data, when the missing data within the stored requested information data is detected by the missing data judging unit;

a missing data receiving unit for receiving the missing data delivered from the delivering apparatus; and

a data delivering unit for performing the streaming delivery of the stored requested information data and the missing data received by the missing data receiving unit to the terminal device.

8. The data communication apparatus of claim 7,

wherein the data storing unit stores the missing data received by the missing data receiving unit with relating the missing data to the stored requested information data, and

wherein the data delivering unit performs the streaming delivery of the stored requested information data and the missing data stored in the data storing unit to the terminal device.

9. A data communication apparatus for performing communication between a terminal device requesting streaming delivery of a piece of information data and a delivering apparatus holding at least one information data file which includes at least one piece of information data and performing the streaming delivery of the information data requested by the terminal device, the data communication apparatus comprising:

a data storing unit available to store any of the information data file;

a delivery request receiving unit for receiving a delivery request of the streaming delivery of specific information data from the terminal device;

a data checking unit for checking if an information data file including requested information data of which the streaming delivery is requested by the delivery request is stored in the data storing unit, and sending the delivery request to the delivering unit if the information data file including the requested information data is not stored in the data storing unit;

a related data delivery requesting unit for judging if requested information data file which includes the requested information data includes other data than the requested information data at the delivering apparatus when the information data file including the requested information data is not stored in the data storing unit, and sending a related data delivery request to the delivering apparatus for requesting the streaming delivery of other data as related data relating to the requested information data when the requested information data file includes other data;

a data receiving unit for receiving the requested information data delivered from the delivering apparatus in response to the delivery request, and receiving the related data delivered from the delivering apparatus in response to the related data delivery request;

a data delivering unit performing the streaming delivery of the requested information data received by the data receiving unit to the terminal device, and

wherein the data storing unit stores the requested information data received by the data receiving unit, and stores the related data received by the data receiving unit with relating the related data to the requested information data.

10. The data communication apparatus of claim 9, wherein, when the information data file includes other information data than the requested information data, the data receiving unit receives other information data delivered as the related data.

11. The data communication apparatus of claim 9, wherein, when the information data file includes appended data other than the requested information data, the data receiving unit receives the appended data delivered as the related data.

12. The data communication apparatus of claim 9,

wherein the delivering apparatus holds attribute information showing data included in the information data file for each of the information data file held in the delivering apparatus,

wherein the data communication apparatus further comprises:

an attribute information transmission requesting unit for sending an attribute information transmission request to the delivering apparatus for requesting the attribute information of the requested information data file; and

an attribute information receiving unit for receiving the attribute information of the requested information data file from the delivering apparatus, and

wherein the related data delivery requesting unit judges if the requested information data file includes other data than the requested information data based on the attribute information of the requested information data file received by the attribute information data receiving unit.

13. The communication apparatus of claim 9,

wherein the delivering apparatus specifies a data format for each of the information data file and holds the information data file in the data format specified,

wherein the data communication apparatus further comprises

a data converting unit for converting the data format of the requested information data and the related data received by the data receiving unit and generating a corresponding information data file which is the information data file including the requested information data and the related data after converting the data format and having same data format as the requested information data file, and

wherein the data storing unit stores the corresponding information data file generated by the data converting unit.

14. The communication apparatus of claim 13,

wherein the delivering apparatus holds attribute information showing the data format of each of the information data file held,

wherein the data communication apparatus further comprises:

an attribute information transmission requesting unit for sending an attribute transmission request to the delivering apparatus for requesting transmission of the attribute information of the requested information data file; and

an attribute information receiving unit for receiving the attribute information of the requested information data file from the delivering apparatus, and

wherein the data converting unit converts the data format of the requested information data and the related data received by the data receiving unit based on the attribute information of the requested information data file received by the attribute information receiving unit.

15. The data communication apparatus of claim 14, wherein the data delivering unit performs the streaming delivery of the requested information data of which the data format has been converted included in the corresponding information data file stored in the data storing unit to the terminal device.

16. The data communication apparatus of claim 9, wherein, when the information data file including the requested information data is stored in the data storing unit, the data delivering unit performs the streaming delivery of the requested information data from the data storing unit to the terminal device.

18. A data communication method for performing communication between a terminal device for requesting streaming delivery of a piece of information data and a delivering apparatus holding at least one piece of information data and performing the streaming delivery of the information data requested by the terminal device, the method comprising:

recording any piece of the information data;

receiving a delivery request of the streaming delivery of specific information data from the terminal device;

checking if requested information data of which the streaming delivery is requested by the delivery request is recorded by the recording, and sending the delivery request to the delivering apparatus if the requested information data is not recorded by the recording;

receiving delivered requested information data which is the requested information data delivered from the delivering apparatus;

judging an existence of missing data within the delivered requested information data;

performing the streaming delivery of the delivered requested information data received by the receiving to the terminal device; and

sending a missing data notice for informing of the missing data within the delivered requested information data, when the missing data is detected within the delivered requested information data by the judging.

19. A data communication method for performing communication between a terminal device requesting streaming delivery of a piece of information data and a delivering apparatus holding at least one piece of information data and performing the streaming delivery of the information data requested by the terminal device, the method comprising:

recording any piece of the information data;

receiving a delivery request of the streaming delivery of specific information data from the terminal device;

checking if requested information data of which the streaming delivery is requested by the delivery request is recorded by the recording, and sending the delivery request to the delivering apparatus if the requested information data is not recorded by the recording;

receiving delivered requested information data which is the requested information data delivered from the delivering apparatus;

judging an existence of missing data within the delivered requested information data;

performing the streaming delivery of the delivered requested information data received by the receiving to the terminal device;

sending a missing data transmission request to the delivering apparatus for requesting a transmission of the missing data within the delivered requested information data, when the missing data is detected within the delivered requested information data by the judging; and

receiving the missing data from the delivering apparatus, and

wherein the recording records the delivered requested information data received by the receiving, and records the missing data received by the receiving with relating the missing data to the delivered requested information data.

20. A data communication method for performing communication between a terminal device requesting streaming delivery of a piece of information data and a delivering apparatus holding at least one piece of information data and performing the streaming delivery of information data requested by the terminal device, the method comprising:

recording any piece of the information data;

receiving a delivery request of the streaming delivery of specific information data from the terminal device;

checking if requested information data of which the streaming delivery is requested by the delivery request is recorded by the recording;

judging an existence of missing data within the recorded requested information data when the requested information data is recorded by the recording;

sending a missing data transmission request to the delivering apparatus for requesting transmission of the missing data within the recorded requested information data, when the missing data within the recorded requested information data is detected by the judging;

receiving the missing data delivered from the delivering apparatus; and

performing the streaming delivery of the recorded requested information data and the missing data received by the receiving to the terminal device.

21. A data communication method for performing communication between a terminal device requesting streaming delivery of a piece of information data and a delivering apparatus holding at least one information data file which includes at least one piece of information data and performing the streaming delivery of the information data requested by the terminal device, the method comprising:

recording any of the information data file;

receiving a delivery request of the streaming delivery of specific information data from the terminal device;

checking if an information data file including requested information data of which the streaming delivery is requested by the delivery request is recorded by the recording, and sending the delivery request to the delivering apparatus if the information data file including the requested information data is not recorded by the recording;

judging if required information data file which includes the requested information data includes other data than the requested information data at the delivering apparatus when the information data file including the requested information data is not recorded by the recording, and sending a related data delivery request to the delivering apparatus for requesting the streaming delivery of other data as related data relating to the requested information data when the requested information data file includes other data;

receiving the requested information data delivered from the delivering apparatus in response to the delivery request, and receiving the related data delivered from the delivering apparatus in response to the related data delivery request;

performing the streaming delivery of the requested information data received by the receiving to the terminal device, and

wherein the recording records the requested information data received by the receiving, and records the related data received by the receiving with relating the related data to the requested information data.