摘要:
A prefiltering method and apparatus for prefiltering a data stream for pattern matching are provided. The prefiltering method includes: receiving a data stream; loading previously stored filtering policies; filtering the data stream according to the loaded filtering policies and generating additional filtering information regarding the filtered data stream; determining whether to transmit the data stream to a search engine apparatus that performs pattern matching based on the additional filtering information; and transmitting the data stream to the search engine apparatus if the data stream is determined as requiring transmission. Therefore, it is possible to provide a high-performance pattern matching system that can achieve a high precision of pattern matching.
摘要:
A method and apparatus for storing pattern matching data and a pattern matching method using the method and apparatus are provided. The method of storing original data for pattern matching in a pattern matching apparatus includes: dividing the original data into segments of a predetermined size; performing a hash operation on each of the divided segments; determining whether or not the hash operation value of each segment causes a hash collision with a hash operation value stored in a first external memory disposed outside the pattern matching apparatus; and controlling the hash operation value of each segment determined not to cause a hash collision to be stored in the first external memory. According to the method and apparatus, the original data desired to be used for pattern matching can be stored at a faster speed in a pattern matching data storing apparatus.
摘要:
A method of storing a pattern matching policy and a method of controlling an alert message are provided. The method includes (a) generating a content structure as a sub-structure of a header combination structure of a stored traffic pattern which is a policy to be newly applied to a pattern matching apparatus; (b) determining whether a content of the stored traffic pattern is identical to a content of an original traffic pattern stored in advance in the pattern matching apparatus; (c) allocating a content index of the content of the original traffic pattern to the content of the stored traffic pattern if the content of the stored traffic pattern is identical to the content of the original traffic pattern; and (d) determining whether a header combination structure of the original traffic pattern comprises only one content structure or more than one content structure and allocating a header index of the header combination structure of the stored traffic pattern to the header combination structure of the original traffic pattern if the header combination structure of the original traffic pattern is found to comprise only one content structure. Accordingly, it is possible to efficiently use hardware memories with limited storage capacities and effectively perform a pattern matching function.
摘要:
A method and apparatus for storing an intrusion rule are provided. The method stores a new intrusion rule in an intrusion detection system having already stored intrusion rules, and includes: generating combinations of divisions capable of dividing the new intrusion rule into a plurality of partial intrusion rules; calculating the frequency of hash value collisions between each of the generated division combinations and the already stored intrusion rules; dividing the new intrusion rule according to the division combination which has the lowest calculated frequency of hash value collisions; and storing the divided new intrusion rule in a corresponding position of the intrusion detection system. According to the method and apparatus, the size of the storage unit occupied by the intrusion rule can be reduced, and by performing pattern matching, the performance of the intrusion detection system can be enhanced.
摘要:
A method and apparatus for pattern matching using packet reassembly are provided. The pattern matching method using packet reassembly includes: extracting serial information in relation to a current input packet; determining whether or not pattern matching result information in relation to one or more previous packets and/or subsequent packets on the basis of the serial number of the current input packet is already stored; loading the pattern matching result information in relation to the previous packets and/or subsequent packets; and reassembling the loaded pattern matching result information in relation to the previous packets and/or subsequent packets and the current input packet and performing pattern matching with attack patterns which are already stored. Accordingly, by using packet reassembly, a method and apparatus for pattern matching capable of reducing memory usage without lowering the speed can be provided
摘要:
An apparatus and method for managing a session state are provided. The apparatus for managing a session state during transmission control protocol (TCP) handshaking includes: a session index unit producing and managing an index including 5-tuple information of a session corresponding to an input packet; a detailed information manager generating and managing an entry by extracting state information of a session in which a predetermined time does not pass after the session has been completely established, to respond to an intrusion detection against the input packet when the index is produced; a brief information manager generating and managing an entry including state information, which includes states of session connection and disconnection and directionality of the input packet, of a session in which a predetermined time elapses after the session has been completely established; and a search unit searching an index of the session corresponding to the input packet in the session index unit, and, if an index does not exist, searching the brief information manager after the session has been completely established.
摘要:
A suction device has a flexible cup member whose lower surface defines a flat central zone surrounded by an annular zone sloping inwardly and upwardly at an angle of 2.degree. to 10.degree. with the central zone. An article holder, such as a beverage can receptacle, has a rigid circular base centrally secured to the upper surface of the cup member, opposite the central zone thereof. Any tilting or lifting of the article holder attendantly tilts or pulls the central zone of the cup member upwardly, thereby establishing a retentive suction in a self-setting manner.
摘要:
Disclosed herein is a linear compressor wherein a compression unit, including a cylinder and a linear motor, is supported by a frame mounted in a hermetic container. The frame is die cast using diamagnetic zinc having a high forming accuracy, thereby preventing an electromagnetic force of the linear motor from being leaked therethrough, and enabling a reduction in the number of machining times thereof after die casting.
摘要:
Disclosed herein is a linear compressor having a stator cover, which is designed in such a fashion that a section of the stator cover not to be fastened with bolts has a curvature smaller than the remaining section thereof to be fastened with the bolt so as to be reduced in size thereof. This enables the stator cover to be spaced apart from the shell by a sufficient distance, thereby achieving a size reduction of the shell and a small-scale linear compressor.
摘要:
Compact cosmetic case with airtight sealed structure, which has a simple construction and enhances its airtight sealed effect to prevent a leakage of cosmetics, such as powder, thus improving quality, increasing productivity and reducing the production costs. The compact cosmetic case includes a body, an inner casing to contain the powder, an inner lid hinged the inner casing and having a powder puff seat, and an outer lid hinged to the body and having a locking part. A groove is formed around an upper surface of the inner casing, with liquid rubber filling the groove to form a rubber seal. A locking hole is formed on the inner casing, while a locking lever having a locking projection is formed on the inner lid to be locked to the locking hole.