CA2205021C - Method for sending messages from a lower-level controller to a higher-level controller - Google Patents
Method for sending messages from a lower-level controller to a higher-level controller Download PDFInfo
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- CA2205021C CA2205021C CA002205021A CA2205021A CA2205021C CA 2205021 C CA2205021 C CA 2205021C CA 002205021 A CA002205021 A CA 002205021A CA 2205021 A CA2205021 A CA 2205021A CA 2205021 C CA2205021 C CA 2205021C
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
- H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
- H04L1/18—Automatic repetition systems, e.g. Van Duuren systems
- H04L1/1803—Stop-and-wait protocols
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/22—Arrangements for detecting or preventing errors in the information received using redundant apparatus to increase reliability
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- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Detection And Prevention Of Errors In Transmission (AREA)
- Communication Control (AREA)
- Maintenance And Management Of Digital Transmission (AREA)
- Data Exchanges In Wide-Area Networks (AREA)
- Selective Calling Equipment (AREA)
Abstract
An existing redundant physical path structure should be used for sending (fault) messages from a lower-level controller to a higher-level controller, without unnecessarily having to load the processing capacity of the higher-level controller by redundant messages in the process.
The invention achieves this aim in that a message is first of all transmitted via each transmission path, and a further message is always sent as soon as an acknowledgement of a previous message is received, the further message being sent via that transmission path via which the acknowledgement was received.
The invention achieves this aim in that a message is first of all transmitted via each transmission path, and a further message is always sent as soon as an acknowledgement of a previous message is received, the further message being sent via that transmission path via which the acknowledgement was received.
Description
a - .-cr. ~ ~~ i J ' -' ";" T ~,i:SLATIQP~
Description method for sending messages from a lower-level controller to a higher-level controller The invention is based on the object of using an existing redundant physical path structure for sexiding (fault) messages from a lower-level controller to a higher-level controller, without unnecessarily having to load the processing capacity of the higher-level controller by redundant fault messages in the process.
If, for example, port faults occur on the peripheral in a switching system, then these events must be reported as quicltly as possible to a higher-level controller in order to allow call attempts to such defective subscriber ports to be rejected as early as possible.
For reliability reasons, in an existing redundant physical path structure, peripheral devices always trans-mit such fault messages in parallel, that is to say a fault message is reported to the higher-level controller simultaneously via at least two different physical paths.
Such a procedure is disclosed, for example, in the document EP-A-0 033 228.
However, as a result of said procedure, the processing capacity of the higher-level controller a.s used more than once for one and the same item of information, namely one fault message.
The invention is based on the object of using an existing redundant physical path structure for sending (fault) messages from a lower-level controller to a higher-level controller, without unnecessarily having to REP?~ACEMENT SHEET
Description method for sending messages from a lower-level controller to a higher-level controller The invention is based on the object of using an existing redundant physical path structure for sexiding (fault) messages from a lower-level controller to a higher-level controller, without unnecessarily having to load the processing capacity of the higher-level controller by redundant fault messages in the process.
If, for example, port faults occur on the peripheral in a switching system, then these events must be reported as quicltly as possible to a higher-level controller in order to allow call attempts to such defective subscriber ports to be rejected as early as possible.
For reliability reasons, in an existing redundant physical path structure, peripheral devices always trans-mit such fault messages in parallel, that is to say a fault message is reported to the higher-level controller simultaneously via at least two different physical paths.
Such a procedure is disclosed, for example, in the document EP-A-0 033 228.
However, as a result of said procedure, the processing capacity of the higher-level controller a.s used more than once for one and the same item of information, namely one fault message.
The invention is based on the object of using an existing redundant physical path structure for sending (fault) messages from a lower-level controller to a higher-level controller, without unnecessarily having to REP?~ACEMENT SHEET
load the processing capacity of the higher-level controller by redundant fault messages in the process.
Exemplary embodiments of the invention will be explained in more detail, with reference to the drawing, in the following text.
The invention ensures that events are reported rapidly to the higher-level controller, since all the transmission paths are used and the best transmission path, that is to say the fastest transmission path, is always chosen for sending an event.
The method according to the invention also achieves automatic load matching since, on the basis of the method according to the invention, fewer event messages are sent, automatically, via those transmission paths which cannot respond as quickly with an acknowledgement because they are more highly loaded. The method according to the invention thus operates even when a path is no longer available, or has failed.
One embodiment of the invention is a refinement based on a control structure which, apart from the central controller, also comprises intermediate controllers, which likewise require the messages from the lower-level controller for processing, and which are in each case located in the transmission path between the lower-level controller and the higher-level controller. In the case of said control structure, the refinement on the one hand results in the messages being transmitted as quickly as possible and without redundancy to the higher-level controller, and also ensures that the messages are transmitted completely and without redundancy to each of the intermediate controllers.
Exemplary embodiments of the invention will be explained in more detail, with reference to the drawing, in the following text.
The invention ensures that events are reported rapidly to the higher-level controller, since all the transmission paths are used and the best transmission path, that is to say the fastest transmission path, is always chosen for sending an event.
The method according to the invention also achieves automatic load matching since, on the basis of the method according to the invention, fewer event messages are sent, automatically, via those transmission paths which cannot respond as quickly with an acknowledgement because they are more highly loaded. The method according to the invention thus operates even when a path is no longer available, or has failed.
One embodiment of the invention is a refinement based on a control structure which, apart from the central controller, also comprises intermediate controllers, which likewise require the messages from the lower-level controller for processing, and which are in each case located in the transmission path between the lower-level controller and the higher-level controller. In the case of said control structure, the refinement on the one hand results in the messages being transmitted as quickly as possible and without redundancy to the higher-level controller, and also ensures that the messages are transmitted completely and without redundancy to each of the intermediate controllers.
A further embodiment of the invention is set forth. In the absence of acknowledgement (time-out of the timer), this refinement allows the message which has not been acknowledged to be sent via another transmission path.
In addition, the fact that the timer has timed out can be reported to a monitoring device, which initiates a check of the corresponding transmission path on the basis of this.
The time duration of the timer can be set generously, since a further message is in fact produced via the same transmission path only if an acknowledgement has already been received.
The refinement of the data structure as a chain structure makes it possible to link subsequent event messages.
In accordance with one aspect of the invention, there is provided a method for sending a plurality of respectively different messages from a lower-level controller to a higher-level controller, a similar plurality of bidirectional physical transmission paths being provided for sending the messages, the method comprising the steps of: first transmitting the messages, for initialization, via the transmission paths, each of the messages being transmitted via a respective one of the transmission paths;
acknowledging each message, which is received by the higher-level controller, to the lower-level controller, each respective acknowledgement being sent back via the respective transmission path by which the respective message was received; and sending a further message as soon as an acknowledgement of a previous message is received, each further message being sent via the respective transmission path by which the respective acknowledgement was received.
- 3a -In accordance with another aspect of the invention there is provided a transmitting device for sending a plurality of respectively different messages from a lower-level controller to a higher-level controller, comprising:
a data structure which buffer-stores messages in the lower-level controller, said messages being intended to be sent to a higher-level controller via a similar plurality of bidirectional transmission paths; one pointer per transmission path which, for each path, points to a next message to be sent within the data structure, after a message having been sent, the respective pointer being moved to the next message to be sent; a means for initialization which initializes the transmission of the messages via the transmission paths, each of the messages being transmitted via a respective one of the transmission paths; and a means for transmission which always sends a message which is defined by the respective pointer to be the next to be sent, whenever a respective acknowledgement for a previous message has been received by the lower-level controller, the next message being sent via the respective transmission path by which the last acknowledgement was received.
FIG 1 shows, by way of example, a real-time system, namely a switching system, in which the method according to the invention is used.
The main item in the illustrated switching system is a central switching network SN, to which a plurality of line trunk groups LTG and a coordination processor CP are connected.
A line trunk group LTG in each case comprises one group processor, which controls it and which, in addition, contains elements of the call processing software.
- 3b -The coordination processor CP controls the entire switching system and, in particular, contains elements of the call processing software and of the operation and maintenance software.
A plurality of digital line units DLU, which preconcentrate the traffic in the direction of the line trunk groups LTG, are in each case connected to one line trunk group LTG.
A digital line unit DLU contains a plurality of subscriber line modules SLMA, which produce the basic connection from a subscriber to the switching system.
If the digital line unit now records port fault messages from the subscriber line modules SLMA, then these messages must be reported as quickly as possible to the coordination processor, in order that it can reject call attempts to such defective subscriber ports as early as possible.
_ c~ _ v FIG 2 shows a device for receiving fault messages in a peripheral device, for example a DLU, in the above-mentioned switching system.
The device comprises a chain structure RS, which can receive n port fault messages, as well as trans mission .pointers PTRx and PTRy, ,which point to that (data) element which is in each case to be sent next.
The mechanism which is produced with the aid of this device for handling the chain structure, and thus for sending fault messages, will be described in more detail in the following text.
At the start of the handling process, both trans-mission pointers point to the element 1. The handling thus starts with the transmission of a message from the element 1 to the x line trunk group, and by incrementing both transmission pointers to the element 2. In addition, a monitoring timer is started, which monitors the time until the return message (acknowledgement) is received from the x line trunk group.
Next, the message M2 is transmitted from the element 2 via the transmission pointer PTRy, a further timer a.s started, and both transmission pointers are then incremented by one element again. This completes the initialization of the mechanism, and both transmission pointers now point to the element 3.
The further handling and the further transmission of error messages are now carried out as a function of the arrival of acknowledgements from the line trunk groups. If, for example, the acknowledgement xQl arrives from the line trunk group LTGx for the message M1 from element l, then this is noted appropriately in the element 1. In this case,~~the next message (in this case message M3) is sent for further handling, addressed by the PTRx, via the path on the x-side, that is to say the , x-LTG. Both transmission pointers are then incremented by one element again. This case is illustrated in FIG 3.
The procedure in the other case, namely on recep-tion of an acknowledgement from the line trunk group LTGy, is analogous, that is to say the acknowledgement yQ2 is in this case noted in the corresponding element and, addressed via the transmission pointer PTRy, a message is transmitted via the y-side, that is to say the line trunk group LTGy,~to the coordination processor.
Thus, in principle, in the method according to the invention, the next element is not sent unless an X
acknowledgement or a Y-acknowledgement has already been received. In this case, after the two transmission pointers have been incremented, the next element is sent via that transmission path via which the acknowledgement has already been received. As a deviation from this mechanism, two successive elements are first of all transmitted on the X-side and Y-side for initialization of the method, without having to wait for the acknowledgement of the first element before the second element is transmitted.
~ FIG 4 shows the position of the transmission pointers at the end of the first pass through the RS. In FIG 4, it is assumed that the element (n-1) has been sent via the LTGy.
After the elements (n-1) have been transmitted, both transmission pointers are set to the element n.
After the acknowledgement character yQ (n-1) has been received for the element (n-1), the message Mn, addressed via the transmission pointer PTRy, is sent via the y-side path, that is to say the line trunk group LTGy. Both transmission pointers are thus once again set to the element 1.
In addition to ~ this, the receipt of the acknowledgement yQ (n-1) means that all the expected acknowledgements (with the exception of the acknowledge-meat yQ(n)), have already been received on the y-side. In contrast to this, no such statement may yet be made on the x-side, that is to say only acknowledgements up to xQ
.(n-k) have.been received by this time on the x-side, k being an integer which is still unknown.
Since, before the second pass through the chain structure which now follows, it has been presupposed that the element (n-1) has already received the acknowledge-ment character yQ (n-1), two cases may now occur in the second pass, namely a case a, in which the acknowledge-ment character yQn for the message Mn has been received as the last acknowledgement character before the start of the second pass, and a case b, in which an acknowledge-went character xQ has been received for the element (n -k) as the last acknowledgement character before the start of the second pass, it being necessary in case b for the messages M (n-k+1) to Mn have been sent via the y-side.
v-FIG 5 shows the two cases a and b mentioned above.
In case a, after the acknowledgement yQn has been received for the message Mn, the message Ml is sent as the next message via the y-path. Although, before the message M1 is sent, both pointers still point to the same element as a result of the first pass, namely to the element l, an acknowledgement has, however, already been received on the x-side for the message Ml in the first pass, for Which reason only the y-side transmission pointer is now incremented. In contrast, the transmission pointer PTRx remains at the element 1 in this ease.
In case b, receipt of the acknowledgement xQ (n-k) for the message M (n-k) confirms that the x-side transmission pointer is pointing to an element which has already been sent. In this case, the x-side transmission pointer a.s incremented until an element which is still to be transmitted (an element without an x acknowledgement) is found on the x-side. In contrast, the y-side trans-mission pointer remains at the element 1 in this case.
Thus, the chain structure has been dealt with completely after two passes for the x-side and y-side, provided no new elements have been attached or linked to the end. In principle, the end criterion for one side is satisfied when there are no more elements to be trans-mitted during an entire pass.
In addition, the fact that the timer has timed out can be reported to a monitoring device, which initiates a check of the corresponding transmission path on the basis of this.
The time duration of the timer can be set generously, since a further message is in fact produced via the same transmission path only if an acknowledgement has already been received.
The refinement of the data structure as a chain structure makes it possible to link subsequent event messages.
In accordance with one aspect of the invention, there is provided a method for sending a plurality of respectively different messages from a lower-level controller to a higher-level controller, a similar plurality of bidirectional physical transmission paths being provided for sending the messages, the method comprising the steps of: first transmitting the messages, for initialization, via the transmission paths, each of the messages being transmitted via a respective one of the transmission paths;
acknowledging each message, which is received by the higher-level controller, to the lower-level controller, each respective acknowledgement being sent back via the respective transmission path by which the respective message was received; and sending a further message as soon as an acknowledgement of a previous message is received, each further message being sent via the respective transmission path by which the respective acknowledgement was received.
- 3a -In accordance with another aspect of the invention there is provided a transmitting device for sending a plurality of respectively different messages from a lower-level controller to a higher-level controller, comprising:
a data structure which buffer-stores messages in the lower-level controller, said messages being intended to be sent to a higher-level controller via a similar plurality of bidirectional transmission paths; one pointer per transmission path which, for each path, points to a next message to be sent within the data structure, after a message having been sent, the respective pointer being moved to the next message to be sent; a means for initialization which initializes the transmission of the messages via the transmission paths, each of the messages being transmitted via a respective one of the transmission paths; and a means for transmission which always sends a message which is defined by the respective pointer to be the next to be sent, whenever a respective acknowledgement for a previous message has been received by the lower-level controller, the next message being sent via the respective transmission path by which the last acknowledgement was received.
FIG 1 shows, by way of example, a real-time system, namely a switching system, in which the method according to the invention is used.
The main item in the illustrated switching system is a central switching network SN, to which a plurality of line trunk groups LTG and a coordination processor CP are connected.
A line trunk group LTG in each case comprises one group processor, which controls it and which, in addition, contains elements of the call processing software.
- 3b -The coordination processor CP controls the entire switching system and, in particular, contains elements of the call processing software and of the operation and maintenance software.
A plurality of digital line units DLU, which preconcentrate the traffic in the direction of the line trunk groups LTG, are in each case connected to one line trunk group LTG.
A digital line unit DLU contains a plurality of subscriber line modules SLMA, which produce the basic connection from a subscriber to the switching system.
If the digital line unit now records port fault messages from the subscriber line modules SLMA, then these messages must be reported as quickly as possible to the coordination processor, in order that it can reject call attempts to such defective subscriber ports as early as possible.
_ c~ _ v FIG 2 shows a device for receiving fault messages in a peripheral device, for example a DLU, in the above-mentioned switching system.
The device comprises a chain structure RS, which can receive n port fault messages, as well as trans mission .pointers PTRx and PTRy, ,which point to that (data) element which is in each case to be sent next.
The mechanism which is produced with the aid of this device for handling the chain structure, and thus for sending fault messages, will be described in more detail in the following text.
At the start of the handling process, both trans-mission pointers point to the element 1. The handling thus starts with the transmission of a message from the element 1 to the x line trunk group, and by incrementing both transmission pointers to the element 2. In addition, a monitoring timer is started, which monitors the time until the return message (acknowledgement) is received from the x line trunk group.
Next, the message M2 is transmitted from the element 2 via the transmission pointer PTRy, a further timer a.s started, and both transmission pointers are then incremented by one element again. This completes the initialization of the mechanism, and both transmission pointers now point to the element 3.
The further handling and the further transmission of error messages are now carried out as a function of the arrival of acknowledgements from the line trunk groups. If, for example, the acknowledgement xQl arrives from the line trunk group LTGx for the message M1 from element l, then this is noted appropriately in the element 1. In this case,~~the next message (in this case message M3) is sent for further handling, addressed by the PTRx, via the path on the x-side, that is to say the , x-LTG. Both transmission pointers are then incremented by one element again. This case is illustrated in FIG 3.
The procedure in the other case, namely on recep-tion of an acknowledgement from the line trunk group LTGy, is analogous, that is to say the acknowledgement yQ2 is in this case noted in the corresponding element and, addressed via the transmission pointer PTRy, a message is transmitted via the y-side, that is to say the line trunk group LTGy,~to the coordination processor.
Thus, in principle, in the method according to the invention, the next element is not sent unless an X
acknowledgement or a Y-acknowledgement has already been received. In this case, after the two transmission pointers have been incremented, the next element is sent via that transmission path via which the acknowledgement has already been received. As a deviation from this mechanism, two successive elements are first of all transmitted on the X-side and Y-side for initialization of the method, without having to wait for the acknowledgement of the first element before the second element is transmitted.
~ FIG 4 shows the position of the transmission pointers at the end of the first pass through the RS. In FIG 4, it is assumed that the element (n-1) has been sent via the LTGy.
After the elements (n-1) have been transmitted, both transmission pointers are set to the element n.
After the acknowledgement character yQ (n-1) has been received for the element (n-1), the message Mn, addressed via the transmission pointer PTRy, is sent via the y-side path, that is to say the line trunk group LTGy. Both transmission pointers are thus once again set to the element 1.
In addition to ~ this, the receipt of the acknowledgement yQ (n-1) means that all the expected acknowledgements (with the exception of the acknowledge-meat yQ(n)), have already been received on the y-side. In contrast to this, no such statement may yet be made on the x-side, that is to say only acknowledgements up to xQ
.(n-k) have.been received by this time on the x-side, k being an integer which is still unknown.
Since, before the second pass through the chain structure which now follows, it has been presupposed that the element (n-1) has already received the acknowledge-ment character yQ (n-1), two cases may now occur in the second pass, namely a case a, in which the acknowledge-ment character yQn for the message Mn has been received as the last acknowledgement character before the start of the second pass, and a case b, in which an acknowledge-went character xQ has been received for the element (n -k) as the last acknowledgement character before the start of the second pass, it being necessary in case b for the messages M (n-k+1) to Mn have been sent via the y-side.
v-FIG 5 shows the two cases a and b mentioned above.
In case a, after the acknowledgement yQn has been received for the message Mn, the message Ml is sent as the next message via the y-path. Although, before the message M1 is sent, both pointers still point to the same element as a result of the first pass, namely to the element l, an acknowledgement has, however, already been received on the x-side for the message Ml in the first pass, for Which reason only the y-side transmission pointer is now incremented. In contrast, the transmission pointer PTRx remains at the element 1 in this ease.
In case b, receipt of the acknowledgement xQ (n-k) for the message M (n-k) confirms that the x-side transmission pointer is pointing to an element which has already been sent. In this case, the x-side transmission pointer a.s incremented until an element which is still to be transmitted (an element without an x acknowledgement) is found on the x-side. In contrast, the y-side trans-mission pointer remains at the element 1 in this case.
Thus, the chain structure has been dealt with completely after two passes for the x-side and y-side, provided no new elements have been attached or linked to the end. In principle, the end criterion for one side is satisfied when there are no more elements to be trans-mitted during an entire pass.
The application of the invention is, of course, not limited to two transmission paths x aad y aecordiag to the exemplary embodiment, but can also be applied to more than two transmission paths in an analogous manner.
Furthermore, a.t is not essential, as in the exemplary embodiment, for there to be intermediate controllers LTGx and LTGy on the transmission paths x and y, which inter-mediate controllers LTGx and LTGy likewise have to be supplied with all the messages, for which reason the chain structure KS must be run through a second time in the course of the transmission method in the case of the exemplary embodiment.
Furthermore, a.t is not essential, as in the exemplary embodiment, for there to be intermediate controllers LTGx and LTGy on the transmission paths x and y, which inter-mediate controllers LTGx and LTGy likewise have to be supplied with all the messages, for which reason the chain structure KS must be run through a second time in the course of the transmission method in the case of the exemplary embodiment.
Claims (5)
.
1. A method for sending a plurality of respectively different messages from a lower-level controller to a higher-level controller, a similar plurality of bidirectional physical transmission paths being provided for sending the messages, the method comprising the steps of:
first transmitting the messages, for initialization, via the transmission paths, each of the messages being transmitted via a respective one of the transmission paths;
acknowledging each message, which is received by the higher-level controller, to the lower-level controller, each respective acknowledgement being sent back via the respective transmission path by which the respective message was received; and sending a further message as soon as an acknowledgement of a previous message is received, each further message being sent via the respective transmission path by which the respective acknowledgement was received.
first transmitting the messages, for initialization, via the transmission paths, each of the messages being transmitted via a respective one of the transmission paths;
acknowledging each message, which is received by the higher-level controller, to the lower-level controller, each respective acknowledgement being sent back via the respective transmission path by which the respective message was received; and sending a further message as soon as an acknowledgement of a previous message is received, each further message being sent via the respective transmission path by which the respective acknowledgement was received.
2. The method as claimed in claim 1, wherein:
the messages are sent via intermediate controlllers in the transmission paths to the higher-level controller, each of which intermediate controllers likewise requires all the messages for processing;
each message which is received by an intermediate controller is acknowledged to the lower-level controller;
the acknowledgements are stored in a message-specific and transmission-path-specific manner in the lower-level controller;
after messages have been sent for the first time, all messages are sent at least one further time in a direction of the higher-level controller, the intermediate controllers no longer passing these messages on to the higher-level controller, and the lower-level controller using the stored acknowledgements to ensure that a message which has already been acknowledged by an intermediate controller is not sent to said intermediate controller again.
the messages are sent via intermediate controlllers in the transmission paths to the higher-level controller, each of which intermediate controllers likewise requires all the messages for processing;
each message which is received by an intermediate controller is acknowledged to the lower-level controller;
the acknowledgements are stored in a message-specific and transmission-path-specific manner in the lower-level controller;
after messages have been sent for the first time, all messages are sent at least one further time in a direction of the higher-level controller, the intermediate controllers no longer passing these messages on to the higher-level controller, and the lower-level controller using the stored acknowledgements to ensure that a message which has already been acknowledged by an intermediate controller is not sent to said intermediate controller again.
3. The method as claimed in claim 1 or 2, wherein:
for each transmitted message, receipt of a corresponding acknowledgement is monitored by a timer;
a message for which no acknowledgement has been received by a time an associated timer times out is transmitted once again on another transmission path.
for each transmitted message, receipt of a corresponding acknowledgement is monitored by a timer;
a message for which no acknowledgement has been received by a time an associated timer times out is transmitted once again on another transmission path.
4. A transmitting device for sending a plurality of respectively different messages from a lower-level controller to a higher-level controller, comprising:
a data structure which buffer-stores messages in the lower-level controller, said messages being intended to be sent to a higher-level controller via a similar plurality of bidirectional transmission paths;
one pointer per transmission path which, for each path, points to a next message to be sent within the data structure, after a message having been sent, the respective pointer being moved to the next message to be sent;
a means for initialization which initializes the transmission of the messages via the transmission paths, each of the messages being transmitted via a respective one of the transmission paths; and a means for transmission which always sends a message which is defined by the respective pointer to be the next to be sent, whenever a respective acknowledgement for a previous message has been received by the lower-level controller, the next message being sent via the respective transmission path by which the last acknowledgement was received.
a data structure which buffer-stores messages in the lower-level controller, said messages being intended to be sent to a higher-level controller via a similar plurality of bidirectional transmission paths;
one pointer per transmission path which, for each path, points to a next message to be sent within the data structure, after a message having been sent, the respective pointer being moved to the next message to be sent;
a means for initialization which initializes the transmission of the messages via the transmission paths, each of the messages being transmitted via a respective one of the transmission paths; and a means for transmission which always sends a message which is defined by the respective pointer to be the next to be sent, whenever a respective acknowledgement for a previous message has been received by the lower-level controller, the next message being sent via the respective transmission path by which the last acknowledgement was received.
5. The transmitting device as claimed in claim 4, wherein said data structure is a chain structure, as a result of which messages are linkable into the data structure while messages are being sent from the data structure.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP94117878.2 | 1994-11-11 | ||
| EP94117878 | 1994-11-11 | ||
| PCT/EP1995/004369 WO1996015602A1 (en) | 1994-11-11 | 1995-11-06 | Process for transmitting messages from a secondary control system to a primary control system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2205021A1 CA2205021A1 (en) | 1996-05-23 |
| CA2205021C true CA2205021C (en) | 2005-09-20 |
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ID=8216455
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002205021A Expired - Fee Related CA2205021C (en) | 1994-11-11 | 1995-11-06 | Method for sending messages from a lower-level controller to a higher-level controller |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP0791256B1 (en) |
| JP (1) | JPH09511889A (en) |
| CN (1) | CN1171872A (en) |
| CA (1) | CA2205021C (en) |
| DE (1) | DE59505009D1 (en) |
| WO (1) | WO1996015602A1 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2344789A1 (en) * | 2000-06-27 | 2001-12-27 | Rockwell Electronic Commerce Corporation | Redundant channels over a packet network |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA1171543A (en) * | 1980-01-24 | 1984-07-24 | Billy R. Slater | Industrial control system |
| US4472787A (en) * | 1981-08-12 | 1984-09-18 | Rockwell International Corporation | System for transferring words on a bus with capability to intermix first attempts and retrys |
| US4607256A (en) * | 1983-10-07 | 1986-08-19 | Honeywell, Inc. | Plant management system |
| US4646300A (en) * | 1983-11-14 | 1987-02-24 | Tandem Computers Incorporated | Communications method |
| US4627045A (en) * | 1984-02-14 | 1986-12-02 | Rosemount Inc. | Alternating communication channel switchover system |
-
1995
- 1995-11-06 EP EP95937875A patent/EP0791256B1/en not_active Expired - Lifetime
- 1995-11-06 DE DE59505009T patent/DE59505009D1/en not_active Expired - Lifetime
- 1995-11-06 JP JP8515704A patent/JPH09511889A/en active Pending
- 1995-11-06 WO PCT/EP1995/004369 patent/WO1996015602A1/en active IP Right Grant
- 1995-11-06 CN CN 95197221 patent/CN1171872A/en active Pending
- 1995-11-06 CA CA002205021A patent/CA2205021C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH09511889A (en) | 1997-11-25 |
| EP0791256A1 (en) | 1997-08-27 |
| DE59505009D1 (en) | 1999-03-11 |
| EP0791256B1 (en) | 1999-01-27 |
| CA2205021A1 (en) | 1996-05-23 |
| WO1996015602A1 (en) | 1996-05-23 |
| CN1171872A (en) | 1998-01-28 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |