Abstract: Before packets enter a router, a packing limiting unit abandons out-of-order packets, decreases a window size, and stores temperately part of said out-of-order packets for having packets pass the packet limiting unit with a better efficiency and a precise order. After packets enter said router, a packet retransmission processing unit acquires a characteristic values and messages calculated from each characteristic value of a packet for obtaining the order, size, header, and check bits for assisting in identifying packets, and stores the characteristic values with a link list for saving memory utility. With both the abovementioned methods, problems of out-or-order and retransmission during packets are transmitted, and of an over-used amount of memory, are solved.

Abstract: An Ethernet passive optical network (EPON) ring for providing protection against fiber failures. The optical network unit (ONU) is coupled to the ring fiber by a three-port passive optical splitting module that has three two-way optical passages. By the three two-way optical passages, the OUN receives/transmits data from/to the two ends of the optical line termination (OLT) to provide protection while the fiber failure. Moreover, it provides better authorization of users and simpler collision detection by the two-way transmission of the three-port passive optical splitting module to prevent hackers from invading and to reduce collisions.

Abstract: Before packets enter a router, a packing limiting unit abandons out-of-order packets, decreases a window size, and stores temperately part of said out-of-order packets for having packets pass the packet limiting unit with a better efficiency and a precise order. After packets enter said router, a packet retransmission processing unit acquires a characteristic values and messages calculated from each characteristic value of a packet for obtaining the order, size, header, and check bits for assisting in identifying packets, and stores the characteristic values with a link list for saving memory utility. With both the abovementioned methods, problems of out-or-order and retransmission during packets are transmitted, and of an over-used amount of memory, are solved.

Abstract: A computer-implemented and stream-based virus-detecting method which inspects packets for malicious contents in a network system scans each incoming packet forming input data for virus code. Depending on packet type, when a packet contains virus code, the method either removes the virus code, replaces a segment previously occupied by the virus code with information indicating the existence of the virus code and creates a modified packet by reconstructing a header and a checksum of the packet, or removes the virus without creating a modified packet, or withholds a last packet from reaching its destination address.

Abstract: A method for detecting viruses in macros of a data stream includes a data collecting process, a macro process, and a scanning process. provides improved benefits in efficiency and space requirements under real time environments by only scanning the macros of the collected data for viruses and suspicious instructions.

Abstract: A network traffic scanner and firewall system inspects packets for malicious contents. The system uses a stateful stack inspection method to scan network traffic at multiple levels in varying manners appropriate to the content of the traffic. The system analyzes data streams, data packages, and package contents, as well as decoding and decrypting data when applicable, to determine whether the data are malicious.

Abstract: A system and method comprising providing a plurality of signature strings, inputting a plurality of strings, separating the signature strings into a plurality of signature groups, respectively detecting common features for the signature strings for each of the signature groups and the input strings, comparing the detected common features for each of the signature groups with those of the input strings, and matching the input strings and the signature groups if the detected common features for the signature groups match those of the input strings. In one aspect, the string matching further comprises matching the input strings with the signature strings for those of the signature groups having common features that match the common features of the input strings. In another aspect, the common features comprise distances or gaps between characters in the input strings and the signature strings.

Abstract: An Ethernet passive optical network (EPON) ring for providing protection against fiber failures. The optical network unit (ONU) is coupled to the ring fiber by a three-port passive optical splitting module that has three two-way optical passages. By the three two-way optical passages, the OUN receives/transmits data from/to the two ends of the optical line termination (OLT) to provide protection while the fiber failure. Moreover, it provides better authorization of users and simpler collision detection by the two-way transmission of the three-port passive optical splitting module to prevent hackers from invading and to reduce collisions.