Title:
COMMUNICATION APPARATUS AND TIME SYNCHRONIZATION SYSTEM
Document Type and Number:
WIPO Patent Application WO/2011/077558
Kind Code:
A1
Abstract:
A communication apparatus is connected through a network to a plurality of time servers to each of which respective different ID information has been assigned. The communication apparatus receives a message including time information, which indicates a time timed by a time server, and further including the ID information thereof, and acquires a reception time when the message was received. If the ID information included in the message is the ID information assigned to any one of the plurality of time servers, then the communication apparatus uses both the time information included in the message and the reception time to calculate a time error. When having detected whether any irregularity for a first time server is present, the communication apparatus outputs, to a servo, a time error calculated by use of a message including the ID information assigned to a second time server. The servo uses the time error to calculate an operation amount. A clock changes, based on the operation amount, the clock rate.
Inventors:
KOZAKAI YASUYUKI (JP)
KANDA MITSURU (JP)
KANDA MITSURU (JP)
Application Number:
PCT/JP2009/071632
Publication Date:
June 30, 2011
Filing Date:
December 25, 2009
Export Citation:
Assignee:
TOSHIBA KK (JP)
KOZAKAI YASUYUKI (JP)
KANDA MITSURU (JP)
KOZAKAI YASUYUKI (JP)
KANDA MITSURU (JP)
International Classes:
G06F13/00; G06F1/14
Foreign References:
| JP2007178363A | 2007-07-12 | |||
| JP2009157913A | 2009-07-16 | |||
| JP2009199139A | 2009-09-03 |
Other References:
SVEN MEIER; HANS WEIBEL: "IEEE 1588 applied in the environment ofhigh availability LANs", 2007 PROCEEDINGS ON INTERNATIONAL IEEE SYMPOSIUMON PRECISION TIMING SYNCHRONIZATION (ISPCS, October 2007 (2007-10-01), pages 100 - 104
Attorney, Agent or Firm:
SAKAI, Hiroaki et al. (JP)
Hiroaki Sakai (JP)
Hiroaki Sakai (JP)
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