US 5,331,647 A · Communication apparatus having function to record communication history

Abstract

A communication system comprising a communication path through which a message passes and, a plurality of communication apparatus, each apparatus includes a message transmission function to the communication path, and a read function for reading the message from the communication path. Each communication apparatus has a communication cumulative amount table so as to store the communication cumulative amount of messages transmitted by each communication apparatus as communication history data. The communication apparatus adds the latest communication cumulative amount in the communication cumulative amount table to a message which is transmitted to the communication path. The communication apparatus compares the stored communication cumulative amount table with the received communication cumulative amount. Thus, troubles of the communication subjects in the communication apparatus according to the result of the comparison can be detected. In addition, without complicated operations of each communication apparatus, while the overhead of processes is kept low, it is possible to prevent a bad effect due to a trouble or error of communication apparatus from being propagated to other communication apparatus.

A communication apparatus for communicating information over a communication path between at least one other communication apparatus, said communication apparatus comprising:

transmitting means for transmitting an information packet to said at least one other communication apparatus over said communication path, wherein said information packet comprises an address section indicating a destination of said information packet, a sender identification section indicating which communication apparatus transmitted said information packet, a communication cumulative amount tab, and a main message section;
receiving means for receiving an information packet transmitted from said at least one other communication apparatus over said communication path, wherein said information packet comprises an address section indicating a destination of said information packet, a sender identification section indicating which communication apparatus transmitted said information packet, a communication cumulative amount tab, and a main message section;
and
a comparison process means, said comparison process means including means for storing a communication cumulative table having a plurality of tabs, a tab being added to said table each time said transmitting means transmits a transmit information packet,
wherein each tab comprises a communication cumulative amount individual section and a total section, said communication cumulative amount individual section having communication cumulative vales each representing a quantity of messages transmitted by each said communication apparatus, said total section having a total value representing a sum of said communication cumulative values,
wherein said comparison process means has operational modes, the modes including:
(a) a transmission mode in which said comparison process means transfers a most recently added tab in said stored communication cumulative table to said transmitting means responsive to a communication cumulative amount request from said transmitting means, in which said comparison process means confirms whether said most recently added tab is appended to a message to be transmitted, and in which said comparison process means creates a new tab when transmission of said message is confirmed, a total value in the total section of the new tab and a value corresponding to said communication apparatus in the individual section being incremented, other values in the new tab being the same as the values in the most recently added tab;
and
(b) a reception mode in which said comparison process means extracts a sender identification section and a communication cumulative amount tab from a received information packet, in which said comparison process means confirms that a total value in the total section of said extracted communication cumulative amount tab matches the total value in the total section of a tab in the stored communication cumulative table, in which said comparison process means compares the communication cumulative values of the communication cumulative amount individual section of the tab whose total section includes the matched total value with the communication cumulative values of the communication cumulative amount individual section of the extracted communication cumulative amount tab, and in which said comparison process means creates a new tab when both the total section and communication cumulative amount individual section of the tab of the stored communication cumulative table coincide with the total section and communication cumulative amount individual section of the received communication cumulative amount tab, a total value in the total section of the new tab and a communication cumulative value of a communication apparatus corresponding to the sender identification section extracted from the received information packet in the individual section being incremented, other values in the new tab being the same as the values in the most recently added tab.

6 more elements

Communication apparatus having function to record communication history

Life of this patent

Communication apparatus having function to record communication history

Life of this patent

Abstract

Claims7