Abstract: A method and computer program product for running state machines by the steps of running at least a first and a second state machine in parallel, observing at least the first state machine for at least one first synchronization rule, and changing the state of the second state machine when the first synchronization rule applies.

Abstract: Apparatus for detecting a pattern in a data stream comprises a pattern matching device for receiving the data stream. The pattern matching device comprises one or more rule engines, each rule engine operating under a plurality of state transition rules encoding a plurality of patterns, a first state transition rule including a wildcard state component and a wildcard input component, a second state transition rule including a wildcard state component and a specified input component, and a third state transition rule including a specified state component and a specified input component, the first, second and third rules having differing priorities, and at least one state transition rule including an output component indicating a pattern match. The apparatus is arranged to pass the data stream to each rule engine, and is further arranged to output a signal indicating a pattern match when a state transition rule indicates a pattern match.

Abstract: This invention provides methods, apparatus and systems for decompressing electronic documents. Utility of this invention includes use in validation and parsing of compressed XML documents. An example data processing method comprises receiving a compressed electronic document, decompressing the document and executing an analysis of the document during the decompression. The analysis determines whether the document conforms to defined syntax rules. In one example, a compressed XML document, while it is being decompressed, following receipt, will be parsed and/or validated at the same time.

Abstract: A data processing method comprises receiving an electronically parseable document, scanning the document according to at least one predefined rule to determine if the document is suspicious, and, if the document is determined not to be suspicious, parsing the document with a first parser, and, if the document is determined to be suspicious, parsing the document with a second parser.

Abstract: An apparatus and method suitable for processing an XML document. The method comprises the steps of providing, to a processor, information relating to the structure of the XML document; and providing, to the processor, information obtained by preprocessing the XML document. The apparatus comprises a preprocessor and a processor/parser for performing the method steps.

Abstract: Methods and apparatus are provided for classifying data packets in a data processing device (1) according to a plurality of context-specific sets of processing rules based on context identifiers associated with respective data packets, each context identifier corresponding to a said context-specific rule set to be used for classification of the associated packet, wherein, for each of a predetermined group of data items in each packet, each rule defines a rule range indicating a range of possible values of the corresponding data item for which that rule applies.