What is claimed is:
1. A networked communication system comprising:
at least a first communication unit including a commitment certificate request data provider that generates commitment certificate request data based on unique context data (ucd) associated with the first communication unit and at least a second communication unit and based on user selected commitment data on a per transaction basis;
at least a third communication unit, trusted by the first and second communication unit, that generates a trusted commitment certificate in response to the commitment data and the unique context data; and
at least the second communication unit, being operatively coupled to receive the trusted commitment certificate, and including a trusted commitment certificate verifier.
2. The networked communication system of claim 1 wherein the third communication unit generates the trusted commitment certificate based on at least a-priori user-selectable total commitment limit data.
3. The networked communication system of claim 1 including a commitment certificate update request signal generator to facilitate certificate recharging.
4. The networked communication system of claim 1 wherein the first communication unit includes a unique context data provider wherein the unique context data includes data representing at least data unique to a given transaction context between the first communication unit and the second communication unit.
5. The networked communication system of claim 1 including a commitment allowance data store, operatively coupled to the third communication unit, that contains at least per user commitment allowance data.
6. The networked communication system of claim 5 wherein the third communication unit serves as a commitment certificate generator and generates the commitment certificate based on at least a portion of stored per user commitment allowance data.
7. The networked communication system of claim 5 wherein the per user commitment allowance data includes data representing per transaction liability limits or per transaction commitment limits on a per user basis.
8. The networked communication system of claim 6 wherein the commitment certificate generator updates per user commitment allowance data in response to commitment certificate request data.
9. The networked communication system of claim 8 wherein the first communication unit generates the commitment certificate request data that includes at least the unique context data wherein the unique context data includes data representing a first user associated with the first communication unit, a second user associated with the second communication unit, identification data corresponding to the third communication unit and transaction identification data.
10. The networked communication system of claim 1 wherein the first communication unit provides per transaction user selected commitment data.
11. The networked communication system of claim 1 wherein the commitment certificate generator generates a public key based commitment certificate that contains at least data representing unique context data, condition data, commitment data and a signature from the third communication unit.
12. The networked communication system of claim 1 wherein the unique context data includes data representing at least the third communication unit, the first communication unit or public key associated with the first communication unit, the second communication unit, and a unique transaction identifier seq chosen through the first communication unit.
13. The networked communication system of claim 1 including an anonymity unique context data provider that generates context data as a function of unique context data.
14. The networked communication system of claim 1 including a commitment certificate request verifier, responsive to commitment certificate request data from the first communication unit, that determines whether a commitment certificate has already been issued for given unique context data.
15. A networked communication system comprising:
a first communication unit including a commitment certificate request data provider that generates commitment certificate request data based on unique context data (ucd) associated with the first communication unit and a second communication unit and based on user selected commitment data, user selected commitment issuing condition data, and user selected data fulfilling issuing condition data, on a per transaction basis, and including a unique context data provider wherein the unique context data includes data representing at least transaction identification data unique to a given transaction between the first communication unit and the second communication unit;
a third communication unit, trusted by the first and second communication unit, that generates a trusted commitment certificate in response to the commitment data and the unique context data;
the second communication unit, being operatively coupled to receive the trusted commitment certificate, and including a trusted commitment certificate verifier; and
a commitment allowance data store, operatively coupled to the third communication unit, that contains at least per user commitment allowance data;
wherein the first communication unit generates the commitment certificate request data that includes at least the unique context data wherein the unique context data includes data representing a public key associated with the first communication unit, a second public key associated with the second communication unit, identification data corresponding to the third communication unit and transaction identification data.
16. The networked communication system of claim 15 wherein the trusted commitment certificate includes a public key based commitment certificate that contains at least data representing unique context data, condition data, commitment data and a signature corresponding to the third communication unit.
17. The networked communication system of claim 16 including a commitment certificate request verifier, responsive to commitment certificate request data from the first communication unit, that determines whether a commitment certificate has already been issued for a given unique context data.
18. A method for providing commitment security among users in a computer network comprising the steps of:
providing a first communication unit that is programmed to generate commitment certificate request data that is based on user selected commitment data on a per transaction basis and based on unique context data (ucd) associated with the first communication unit and a second communication unit and
providing a third communication unit, trusted by the first and a second communication unit, that generates a trusted commitment certificate in response to the user selected commitment data and unique context data.
19. The method of claim 18 including generating the trusted commitment certificate based on a-priori user-selectable total commitment limit data.
20. The method of claim 18 including generating a commitment certificate update request signal to facilitate certificate recharging.
21. The method of claim 18 including providing the unique context data to include data representing at least transaction identification data unique to a given transaction between the first communication unit and the second communication unit.
22. The method of claim 18 including storing at least per user commitment allowance data to facilitate determination of whether to issue the trusted commitment certificate.
23. The method of claim 22 including the step of generating the commitment certificate based on at least a portion of stored per user commitment allowance data and on additional issuing condition data.
24. The method of claim 22 wherein the per user commitment allowance data includes data representing per transaction limited liability commitments on a per user basis.
25. The method of claim 23 including updating per user commitment allowance data in response to commitment certificate request data.
26. The method of claim 25 wherein the first communication unit generates the commitment certificate request data that includes at least the unique context data wherein the unique context data includes data representing a first user associated with the first communication unit, a second user associated with the second communication unit, identification data corresponding to the third communication unit and transaction identification data.
27. The method of claim 18 wherein the first communication unit provides per transaction user selected commitment data.
28. The method of claim 18 including generating a public key based commitment certificate that contains at least data representing unique context data, condition data, commitment data and a signature corresponding to the third communication unit.
29. The method of claim 18 including generating anonymity context data as a function of unique context data.
30. The method of claim 18 including determining whether a commitment certificate has already been issued for a given context.
31. The method of claim 18 including generating the commitment certificate request data to based on context specific issuing condition data for use in issuing the trusted commitment certificate.
32. A storage medium comprising
memory containing executable instructions such that when processed by at least one processing unit causes the at least one processing unit to generate and authenticate commitment certificate request data that is based on user selected commitment data on a per transaction basis and based on unique context data (ucd) associated with the first communication unit and a second communication unit and that generates a trusted commitment certificate in response to the user selected commitment data and unique context data.
33. The storage medium of claim 32 including memory containing programming instructions that when processed by a processing unit causes the processing unit to generate the trusted commitment certificate based on a-priori user-selectable total commitment limit data.
34. The storage medium of claim 32 including memory containing programming instructions that when processed by a processing unit causes the processing unit to generate a commitment certificate update request signal to facilitate certificate recharging.
35. The storage medium of claim 33 including memory containing programming instructions that when processed by a processing unit causes the processing unit to provide the unique context data to include data representing at least transaction identification data unique to a given transaction between the first communication unit and the second communication unit.
36. The storage medium of claim 32 including memory containing programming instructions that when processed by a processing unit causes the processing unit to store at least per user commitment allowance data to facilitate determination of whether to issue the trusted commitment certificate.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method for utilizing a memory cartridge connected to a programmable logic controller (PLC), the memory cartridge comprising a plurality of memory segments, the method comprising a plurality of activities comprising:
providing a data log file to the memory cartridge, the data log file having a first head marker that is turned on and a second head marker that is turned on;
comparing a first data log record on the memory cartridge identified by the first head marker and a second data log record on the memory cartridge identified by the second head marker using an error checking technique; and
determining which of the first head marker and the second head marker is erroneous based on a result of the comparison of the first data log record and the second data log record using the error checking technique.
2. The method of claim 1, wherein the error checking technique comprises using a checksum.
3. The method of claim 1, wherein the error checking technique comprises using a Fletcher checksum.
4. The method of claim 1, wherein said activity of comparing the first data log record and the second data log record takes place responsive to a loss of power to the memory cartridge.
5. The method of claim 1, further comprising:
determining that the first head marker relating to the first data log record was written subsequently to the second head marker relating to the second data log record; and
changing the second head marker to a non-head marker.
6. The method of claim 1, further comprising:
determining that the first head marker relating to the first data log record was written subsequently to a second head marker relating to the second data log record; and
disabling the second head marker.
7. The method of claim 1, wherein the data log file is written as a logically circular buffer.
8. The method of claim 7, further comprising:
comparing a position associated with the first head marker to a position associated with the second head marker with respect to a direction of writing of the circular buffer;
determining that the first head marker was written subsequently to the second head marker; and
changing the second head marker to a non-head marker.
9. The method of claim 1, further comprising:
comparing a time stamp associated with the first data log record to a time stamp associated with the second data log record;
determining that the first head marker was written subsequently to the second head marker; and
changing the second head marker to a non-head marker.
10. The method of claim 1, further comprising:
automatically reading the data log file, said reading activity subsequent to a received user input regarding an option to erase the data log file after the reading activity, the user input received responsive to a prompt.
11. The method of claim 1, further comprising:
responsive to an affirmative user input to a prompt corresponding to a selection to erase the data log file, erasing the data log file from the memory cartridge.
12. The method of claim 1, further comprising:
responsive to a negative user input corresponding to a selection to erase the data log file, not erasing the data log file from the memory cartridge.
13. The method of claim 1, further comprising:
providing a default selection corresponding to not erasing the data log file after reading the data log file from the memory cartridge.
14. The method of claim 1, further comprising:
providing a default selection corresponding to erasing the data log file after reading the data log file from the memory cartridge.
15. The method of claim 1, further comprising:
writing a third data log record in the data log file responsive to a third head marker, the third head marker indicative of a beginning memory segment for the third data log record to be written in the data log file.
16. The method of claim 1, further comprising:
responsive to a third data log record being written in the data log file, the third data log record associated with a third head marker that is turned on, changing a previous head marker to a record marker in the data log file.
17. The method of claim 1, further comprising:
responsive to the power failure, determining that the first head marker and the second head marker are turned on simultaneously.
18. A method comprising:
responsive to a power failure and based upon a data log structure, comparing a first data log record on a memory cartridge associated with a first marker to a second data log record on the memory cartridge associated with a second marker using an error checking technique, the first data log record and the second data log record being part of a data log file stored on the memory cartridge, the memory cartridge connected to a programmable logic controller (PLC), the memory cartridge comprising a plurality of memory segments, the data log structure stored separately from the data log file on the memory cartridge; and
determining which of the first marker and the second marker is erroneous.
19. A non-transitory computer readable storage medium comprising computer-executable instructions for activities comprising:
responsive to a power failure and based upon a data log structure, comparing a first data log record on a memory cartridge associated with a first marker to a second data log record on the memory cartridge associated with a second marker using an error checking technique, the first data log record and the second data log record being part of a data log file stored on the memory cartridge, the memory cartridge connected to a programmable logic controller (PLC), the memory cartridge comprising a plurality of memory segments, the data log structure stored separately from the data log file on the memory cartridge;
determining which of the first marker and the second marker is erroneous; and automatically reading the data log file, said reading activity subsequent to a received user input regarding an option to erase the data log file after the reading activity, the user input received responsive to a prompt.