Time stamp generating system

• US 20030212828A1
• Filed: 08/20/2002
• Published: 11/13/2003
• Est. Priority Date: 05/08/2002
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Yoshiura, Hiroshi, Miyazaki, Kunihiko, Matsuki, Takeshi, Takaragi, Kazuo, Toyoshima, Hisashi, Susaki, Seiichi, Sasaki, Ryoichi, Matsumoto, Tsutomu, Iwamura, Mitsuru
• Granted Patent: US 7,200,682 B2
• Time in Patent Office: Days
• US Class Current: 709/248
• CPC Class Codes: G06Q 30/06 Buying, selling or leasing transactions
• CPC Class Codes: H04L 9/3297 involving time stamps, e.g. generation of time stamps

Abstract

A time stamp generating system has a time distribution server for generating time data depending on time and a user PC for holding time certification objective digital data. The time distribution server generates time data corresponding to a time point and distributes the time data. The user PC calculates time stamp generating data by using the time certification objective data as an input, acquires the time data generated by the time distribution server, and processes the time data on the basis of the time stamp generating data to obtain a time stamp.

Claims

1. A time stamp generating system comprising:

time data generation means for generating time data corresponding to a time point;

means for calculating time stamp generating data by using time certification objective data as an input; and

means for processing said time data on the basis of said time stamp generating data to extract a time stamp.

2. A time stamp generating system comprising:

a time distribution server for generating time data depending on time point; and

a user PC for holding time certification objective data,

wherein said time distribution server generates time data corresponding to a time point and distributes said time data; and

said user PC calculates time stamp generating data by using said time certification objective data as an input, acquires the time data generated by said time distribution server, and processes said time data on the basis of said time stamp generating data to obtain a time stamp.

3. A time stamp generating system according to claim 2, wherein said time distribution server generates a pseudo-random number series and when generating said time data, extracts a pseudo-random number of a predetermined length corresponding to said time point from said pseudo-random number series to provide said time data.

4. A time stamp generating system according to claim 2, wherein said user PC calculates time stamp generating data by using the time certification objective data as an input and when obtaining said time stamp, acquires partial data of said time data, which partial data is designated by said time stamp generating data, to provide the acquired partial data as said time stamp.

5. A time stamp generating system according to claim 2, wherein said time distribution server transmits time data generated depending on the present time to a plurality of user PC'"'"'s by using a broadcasting communication path.

7. A time stamp generating system according to claim 2, wherein said user PC calculates a secondary time stamp acquiring time and secondary time stamp generating data on the basis of said acquired time data and time certification objective data, and processes said time data at the secondary time stamp acquiring time on the basis of the secondary time stamp generating data to obtain a secondary time stamp.

8. A time stamp generating system according to claim 7, wherein when calculating the secondary time stamp acquiring time and secondary time stamp generating data, said user PC further calculates secondary time distribution server designating data and when acquiring said time data, said user PC obtains secondary time data from the secondary time distribution server designating data.

9. A time stamp generating system according to claim 2, wherein when generating said time data, said time distribution server adds position information of said time distribution server.

6. A time stamp generating system comprising:

a time distribution server for generating time data depending on time; and

a user PC for holding time certification objective digital data,

wherein said user PC calculates time stamp generating data by using the time certification objective data as an input and transmits said time stamp generating data to said time distribution server; and

said time distribution server generates time data corresponding to a time point, receives said time stamp generating data from said user PC, processes said time data on the basis of said time stamp generating data to obtain a time stamp, and transmits said time stamp to said user PC.