Error detection/correction and fault detection/recovery – Data processing system error or fault handling – Reliability and availability
Reexamination Certificate
1998-04-15
2001-03-06
Le, Dieu-Minh T. (Department: 2785)
Error detection/correction and fault detection/recovery
Data processing system error or fault handling
Reliability and availability
C714S002000, C714S016000, C714S717000
Reexamination Certificate
active
06199174
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a network comprising a plurality of station units connected by a ring-like data transmission line enabling circular transmission of communication data in digital form in a single direction and, in particular to an abnormality recovery system in a network capable of maintaining a data transmission function in the network even if communication means being provided for each station unit for governing reception and transmission of communication data falls into an abnormal condition.
2. Description of the Related Art
Hitherto, a network generally has been known which comprises a plurality of station units connected by a ring-like data transmission line enabling circular transmission of communication data in digital form in a single direction.
To exchange communication data between station units in a network configured as described above, first a communication IC for governing reception and transmission of communication data is provided for each station unit and the communication data is sent from the communication IC in the station unit of the transmitting party in a predetermined direction on a data transmission line. The communication IC in the station unit downstream from the transmitting party on the data transmission line determines whether or not the home station unit is specified as the receiving party. If the home station unit is not specified as the receiving party, the communication IC sends the communication data to the station unit downstream from the home station unit. On the other hand, if the home station unit is specified as the receiving party, the communication IC reads the communication data over the data transmission line, thereby exchanging the communication data between the station units.
However, according to the conventional network as described above, if an abnormal condition such as a failure occurs in the communication IC in a station unit at a midpoint position on the route between the transmitting party and the receiving party, the communication data cannot be transmitted to station units downstream from the station unit falling into the abnormal condition. Resultantly, a problem of impairing the data transmission function in the network, to be solved is involved.
SUMMARY OF THE INVENTION
It is therefore an object of the invention to provide an abnormality recovery system in a network capable of maintaining a data transmission function in the network by, if communication means for governing reception and transmission of communication data falls into an abnormal condition, allowing communication data to pass through the station unit including the communication means in the abnormal condition and be sent to the next station unit.
In order to achieve the above object, according to the invention, there is provided an abnormality recovery system in a network comprising a plurality of station units connected by a ring-like data transmission line enabling circular transmission of communication data in digital form in a single direction, wherein each of the plurality of station units comprises: reception means for receiving communication data over the data transmission line; transmission means for sending communication data to the data transmission line; communication means for taking the communication data received at the reception means and sending the communication data to the transmission means; a bypass used to bypass the communication means and send the communication data from the reception means to the transmission means; communication abnormality determination means for determining whether or not an abnormality occurs in the communication means; and switch control means, when the communication abnormality determination means determines that an abnormality occurs in the communication means, for performing switch control to switch a communication data route so as to bypass the communication means and send the communication data on the bypass from the reception means to the transmission means.
Further, there is provided an abnormality recovery system in a network comprising a plurality of station units connected by a ring-like data transmission line enabling circular transmission of communication data in digital form in a single direction, wherein each of the plurality of station units comprises: reception means for receiving communication data over the data transmission line; transmission means for sending communication data to the data transmission line; communication means for taking the communication data received at the reception means and sending the communication data to the transmission means; a bypass used to bypass the communication means and send the communication data from the reception means to the transmission means; reception state determination means for monitoring a communication data reception state at the reception means and determining whether or not the reception state is good; arrival determination means for determining whether or not the communication data sent from the transmission means has arrived at the station unit as a receiving party; and switch control means, when the reception state determination means determines that the communication data reception state is good and the arrival determination means determines that the communication data has not arrived at the receiving party, for performing switch control to switch a communication data route so as to bypass the communication means and send the communication data on the bypass from the reception means to the transmission means.
Further, there is provided an abnormality recovery system in a network comprising a plurality of station units connected by a ring-like data transmission line enabling circular transmission of communication data in digital form in a single direction and adopting a master/slave method as a communication method, wherein each of slave station units of the plurality of station units comprises: reception means for receiving communication data over the data transmission line; transmission means for sending communication data to the data transmission line; communication means for taking the communication data received at the reception means and sending the communication data to the transmission means; a bypass used to bypass the communication means and send the communication data from the reception means to the transmission means; communication abnormality determination means for determining whether or not an abnormality occurs in the communication means; and switch control means, when the communication abnormality determination means determines that an abnormality occurs in the communication means, for performing switch control to switch a communication data route so as to bypass the communication means and send the communication data on the bypass from the reception means to the transmission means.
Furthermore, there is provided an abnormality recovery system in a network comprising a plurality of station units connected by a ring-like data transmission line enabling circular transmission of communication data in digital form in a single direction and adopting a master/slave method as a communication method, wherein each of slave station units of the plurality of station units comprises: reception means for receiving communication data over the data transmission line; transmission means for sending communication data to the data transmission line; communication means for taking the communication data received at the reception means and sending the communication data to the transmission means; a bypass used to bypass the communication means and send the communication data from the reception means to the transmission means; reception state determination means for monitoring a communication data reception state at the reception means and determining whether or not the reception state is good; arrival determination means for determining whether or not the communication data sent from the transmission means has arrived at the station unit as a receiving party; and switch control me
Murakami Katsumi
Nakajima Katsutoshi
Nishiyama Hiroshi
Norizuki Akira
Le Dieu-Minh T.
Morgan & Lewis & Bockius, LLP
Yazaki -Corporation
LandOfFree
Abnormality recovery system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Abnormality recovery system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Abnormality recovery system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2522440