Abstract: A method and an apparatus to perform multiple packet payload analysis have been disclosed. In one embodiment, the method includes receiving a plurality of data packets, each of the plurality of data packets containing a portion of a data pattern, determining whether each of the plurality of data packets is out of order, and making and storing a local copy of the corresponding data packet if the corresponding data packet is out of order. Other embodiments have been claimed and described.

Abstract: A method and apparatus for identifying data patterns of a file are described herein. In one embodiment, an exemplary process includes, but is not limited to, receiving a data packet of a data stream containing a file segment of a file originated from an external host and destined to a protected host of a local area network (LAN), the file being transmitted via multiple file segments contained in multiple data packets of the data stream, and performing a data pattern analysis on the received data packet to determine whether the received data packet contains a predetermined data pattern, without waiting for a remainder of the data stream to arrive. Other methods and apparatuses are also described.

Abstract: A method and an apparatus to store information regarding web pages have been disclosed. In one embodiment, the method includes receiving a predetermined type of information regarding a web page in a domain from a server, using a subset of the information to evaluate the web page based on one or more predetermined policies, and locally storing the subset of the information. Other embodiments have been claimed and described.

Abstract: Some embodiments of an efficient string search have been presented. In one embodiment, a string of bytes representing content written in a non-delimited language is received, wherein the content has been classified into a predetermined category. In a single pass through the string of bytes, a set of N-grams is searched for simultaneously. Statistical information on occurrences of the N-grams, if any, in the string of bytes is collected. In some embodiments, a model is generated based on the statistical information, where the model is usable by a content filter to classify content.

Abstract: A method and an apparatus request web pages and content rating information thereof have been disclosed. In one embodiment, the method includes receiving a request from a user for a web page, retrieving content rating of the web page in response to the request, and fetching the web page substantially simultaneously with the retrieving of the content rating in response to the request. Other embodiments have been claimed and described.

Abstract: Some embodiments of on-the-fly pattern recognition with configurable bounds have been presented. In one embodiment, a pattern matching engine is configured based on user input, which may include values of one or more user configurable bounds on searching. Then the configured pattern matching engine is used to search for a set of features in an incoming string. A set of scores is updated based on the presence of any of the features in the string while searching for the features. Each score may indicate a likelihood of the content of the string being in a category. The search is terminated if the end of the string is reached or if the user configurable bounds are met. After terminating the search, the scores are output.

Abstract: Techniques for data pattern analysis using deterministic finite automaton are described herein. In one embodiment, a number of transitions from a current node to one or more subsequent nodes representing one or more sequences of data patterns is determined, where each of the current node and subsequent nodes is associated with a deterministic finite automaton (DFA) state. A data structure is dynamically allocated for each of the subsequent nodes for storing information associated with each of the subsequent nodes, where data structures for the subsequent nodes are allocated in an array maintained by a data structure corresponding to the current node if the number of transitions is greater than a predetermined threshold. Other methods and apparatuses are also described.

Abstract: A training procedure for N-gram based statistical document classification has been disclosed. In one embodiment, a set of N-grams is selected out of a second set of N-grams, each of the N-grams having a sequence of N bytes, where N is an integer. Then a statistical content classification model is generated based on occurrences of the N-grams, if any, in a set of training documents and a set of validation documents. The statistical content classification model is provided to content filters to classify content.

Abstract: A method and apparatus for identifying data patterns of a file are described herein. In one embodiment, an exemplary process includes, but is not limited to, receiving a data packet of a data stream containing a file segment of a file originated from an external host and destined to a protected host of a local area network (LAN), the file being transmitted via multiple file segments contained in multiple data packets of the data stream, and performing a data pattern analysis on the received data packet to determine whether the received data packet contains a predetermined data pattern, without waiting for a remainder of the data stream to arrive. Other methods and apparatuses are also described.

Abstract: Some embodiments of on-the-fly pattern recognition with configurable bounds have been presented. In one embodiment, a pattern matching engine is configured based on user input, which may include values of one or more user configurable bounds on searching. Then the configured pattern matching engine is used to search for a set of features in an incoming string. A set of scores is updated based on the presence of any of the features in the string while searching for the features. Each score may indicate a likelihood of the content of the string being in a category. The search is terminated if the end of the string is reached or if the user configurable bounds are met. After terminating the search, the scores are output.

Abstract: A training procedure for N-gram based statistical document classification has been disclosed. In one embodiment, a set of N-grams is selected out of a second set of N-grams, each of the N-grams having a sequence of N bytes, where N is an integer. Then a statistical content classification model is generated based on occurrences of the N-grams, if any, in a set of training documents and a set of validation documents. The statistical content classification model is provided to content filters to classify content.

Abstract: A method and an apparatus to store content rating information have been disclosed. In one embodiment, the method includes receiving a user request to access a web page, sending a domain name system (DNS) request to a first one of a plurality of DNS servers from a content filtering client to get content rating information of the web page in response to the user request, and receiving from the first one DNS server a DNS response containing the content rating information to the content filtering client. Other embodiments have been claimed and described.

Abstract: Methods and apparatuses for link-based content ratings for pages are described herein. According to one embodiment, statistics for each of multiple pages is determined with respect to one or more predetermined categories based on the content rating of each of the pages. For each of the categories, a set of primary pages having relationships (e.g., links) with one or more secondary pages is selected, where the selected pages probabilistically distinguish from relationships with other pages. Other methods and apparatuses are also described.

Abstract: Techniques for reassembly-free rewriting of out-of-order data packet payload are described herein. In one aspect of the invention, in response to packets received at a network access device from a first network node destined to a second network node, the packets are stored in a buffer within the network access device if the packets need to be modified before sending the packets to the second network node. The original our-of-order packets are dropped and do not reach the second network node. The payloads of the packets stored in the buffer are modified and thereafter, the modified packets with the modified payloads are sent to the second network node. Other methods and apparatuses are also described.

Abstract: A method and an apparatus to perform multiple packet payload analysis have been disclosed. In one embodiment, the method includes receiving a plurality of data packets, each of the plurality of data packets containing a portion of a data pattern, determining whether each of the plurality of data packets is out of order, and making and storing a local copy of the corresponding data packet if the corresponding data packet is out of order. Other embodiments have been claimed and described.

Abstract: A method and an apparatus to perform multiple packet payload analysis have been disclosed. In one embodiment, the method includes receiving a plurality of data packets, each of the plurality of data packets containing a portion of a data pattern, determining whether each of the plurality of data packets is out of order, and making and storing a local copy of the corresponding data packet if the corresponding data packet is out of order. Other embodiments have been claimed and described.