Abstract: A method is provided to verify the computational results of a transaction processing system that includes a parent node a plurality of child nodes. The parent node sends to at least two child nodes an identical request to process a transaction. The transaction is allowed to modify an application's state only if the validity of the result of the processing of the transaction is verified across participating child nodes. Otherwise, the transaction is aborted.

Abstract: An apparatus is provided to verify the computational results of a transaction processing system utilizing a parent node and a plurality of child nodes in a high-availability and scalable fashion. A transaction is executed in an identical manner in two or more participating child nodes, and the transaction is allowed to modify an application's state (e.g., commit) only if the validity of the result of the processing of the transaction is verified across the majority of the participating child nodes. Otherwise, the transaction is aborted. The child nodes may exist within a cloud provider or across multiple cloud providers.

Abstract: A method is provided for controlling whether transactions applied against a database go forward or are aborted on a transaction processing system. A tracking engine identifies an uncompleted transaction to be joined, joins the uncompleted transaction, and collects one or more attributes of the joined uncompleted transaction. The collected one or more attributes become available as a result of the joining of the uncompleted transaction. The collected one or more attributes of the joined uncompleted transaction are compared against rules in a rules engine to determine whether the joined uncompleted transaction goes forward or is aborted. Alternatively, the joined uncompleted transaction is automatically modified so that the collected attributes are in compliance with the rules in the rules engine, thereby allowing the joined uncompleted transaction to go forward and be applied against the database of the transaction processing system.

Abstract: A method is provided for logging non-durable attributes of an uncompleted transaction to a persistent storage medium. A tracking engine identifies an uncompleted transaction to be joined, joins the uncompleted transaction, and collects non-durable attributes of the joined uncompleted transaction. The non-durable attributes of the joined uncompleted transaction are made durable by logging them to the persistent storage medium.

Abstract: An identical request to process a transaction is initiated at a trusted subsystem of a system and a new subsystem of the system. Computed indicia of the transaction from both subsystems are compared at the trusted subsystem. An error condition is generated that indicates a logic error in the new subsystem when the comparison indicates that the computed indicia of the new subsystem does not match the computed indicia of the trusted subsystem. The error condition indicates a lack of transactional integrity in the new subsystem. The new subsystem may be taken out of service after the error condition is generated.

Abstract: An identical request to process a transaction is initiated at multiple nodes or multiple applications, and the results are committed. Subsequent to the commit, indicia regarding the outcome of the processing are compared, and the transaction is rolled back if the comparison indicates that the processing was incorrect.

Abstract: A system is provided for mitigating partially correlated failure modes to increase application availability. The system includes a plurality of nodes connected by a computer network, each node configured to run an instance of the same application, a failure analysis engine configured to maintain current availability statistics for the nodes of the system, calculate current mean time to failure (MTTF) for the system as a function of the current time from the availability statistics, and compare the current MTTF to a plurality of threshold values, each of the threshold values corresponding to one or more actions to be taken to increase application availability, and a failure prevention engine that performs the one or more actions to increase application availability.

Abstract: A method is provided to verify the computational results of a transaction processing system utilizing cloud resources in a high-availability and scalable fashion. A transaction is allowed to modify an application's state only if the validity of the result of the processing of the transaction is verified across the majority of the participating child nodes in the cloud. Otherwise, the transaction is aborted.

Abstract: A corrupted database is returned to a correct state by rolling forward or backward through a change queue and applying changes to the database in a selective manner. Changes that did not cause the corruption are applied without modification when rolling forward or are skipped when rolling backward. Changes that caused corruption are addressed when rolling forward, such as by being ignored or modified and then applied. Changes that caused corruption are corrected when rolling backward.

Abstract: Both redo operations and undo operations are provided for returning a database that is corrupted to a correct state. When corruption of the database is detected, an automatic selection is made of one or more operations from the redo operations and undo operations for returning the database that is corrupted to a correct state. The selected one or more redo and undo operations are then performed on the database, thereby returning the database that is corrupted to a correct state.

Abstract: A method is provided to verify the computational results of a transaction processing system utilizing cloud resources. A transaction is allowed to modify an application's state only if the validity of the result of the processing of the transaction is verified across the majority of the participating child nodes in the cloud. Otherwise, the transaction is aborted.

Abstract: A method is provided to verify the computational results of a transaction processing system. A transaction is allowed to modify an application's state only if the validity of the result of the processing of the transaction is verified. Otherwise, the transaction is aborted.

Abstract: Transactions are applied against a database on a transaction processing system. A tracking engine identifies an uncompleted transaction to be joined, joins the uncompleted transaction, and collects one or more non-durable attributes of the joined uncompleted transaction. Collected attributes of the joined uncompleted transaction are compared against rules in a rules engine that are applicable to the transaction to determine whether an applicable rule in the rules engine is met. The joined uncompleted transaction is allowed to go forward and be applied against the database of the transaction processing system using a synchronous replication engine when the applicable rule is met, and an asynchronous replication engine when the applicable rule is not met. Alternatively, the joined uncompleted transaction is allowed to go forward using a replication engine that replicates using encryption when the applicable rule is met, or replicates unencrypted when the applicable rule is not met.

Abstract: Locks placed on corresponding objects held in a plurality of databases located at different nodes in a network during replication are released in accordance with fairness criteria. Propagation delays are determined between a transaction initiating node and one or more other nodes in the network. An object is locked during a transaction being executed at the transaction initiating node. Corresponding objects are locked at one or more other nodes in the network that are manipulated as a result of the replication Upon determining that the object locks should be released, the propagation delays are used to determine when to release the object locks so that all of the object locks at the one or more other nodes are released in accordance with the fairness criteria.

Abstract: Both redo operations and undo operations are provided for returning a database that is corrupted to a correct state. When corruption of the database is detected, an automatic selection is made of one or more operations from the redo operations and undo operations for returning the database that is corrupted to a correct state. The selected one or more redo and undo operations are then performed on the database, thereby returning the database that is corrupted to a correct state.

Abstract: A corrupted database is returned to a correct state by rolling forward or backward through a change queue and applying changes to the database in a selective manner. Changes that did not cause the corruption are applied without modification when rolling forward or are skipped when rolling backward. Changes that caused corruption are addressed when rolling forward, such as by being ignored or modified and then applied. Changes that caused corruption are corrected when rolling backward.

Abstract: A method is provided of alerting a merchant after completion of a transaction that the payment instrument used for the transaction has been identified as being suspect. A reporting processor receives payment instrument indicia regarding payment instruments which have been used for completion of transactions by the merchant, and payment instrument indicia regarding payment instruments which have been identified as being suspect. The reporting processor compares the payment instrument indicia which have been used for completion of transactions by the merchant with the payment instrument indicia which have been identified as being suspect to identify matching payment instrument indicia. The matching payment instrument indicia is associated with suspect payment instrument indicia used by the merchant for completion of the transaction. An electronic communication is provided to the merchant regarding any identified suspect payment instrument indicia.

Abstract: A method is provided for processing base level data of a change queue that is not serialized at the logical level. The base level change queue data is transaction data previously posted to a source database. A logical replication engine is provided to replicate and post the change queue data to a target database in the order that the transaction data is stored in the change queue. Upon detection in the logical replication engine of change queue data that is not serialized at the logical level, the change queue data is reserialized at the logical level before the logical replication engine applies the change queue data to the target database. The change queue data that is not serialized at the logical level may be posted to the target database using asynchronous database access.

Abstract: A method of performing transactions in accordance with fairness criteria is provided wherein one of a plurality of entities initiates a transaction on an object at a database. The steps or operations of the initiated transaction are immediately processed up to the transaction ownership step. Propagation delays are determined between the database and at least some of the other entities that are capable of initiating transactions to the database. The propagation delays and a fairness criteria is used to determine the fair propagation delay period. Upon determining that the fair propagation delay period has been exceeded, it is detecting whether any of the other entities initiated a transaction on the same object during the fair propagation delay time period. If not, then the transaction initiating entity performs the transaction ownership step on the initiated transaction.

Abstract: Locks placed on corresponding objects held in a plurality of databases located at different nodes in a network during replication are released in accordance with fairness criteria. Propagation delays are determined between a transaction initiating node and one or more other nodes in the network. An object is locked during a transaction being executed at the transaction initiating node. Corresponding objects are locked at one or more other nodes in the network that are manipulated as a result of the replication Upon determining that the object locks should be released, the propagation delays are used to determine when to release the object locks so that all of the object locks at the one or more other nodes are released in accordance with the fairness criteria.