Abstract: A method and apparatus are provided for computing a CRC value for a data stream packet with a modified portion and an unmodified portion extending a distance to the end of the data stream packet by computing a first CRC value from the unmodified portion, computing a second CRC value from the modified portion, adjusting the second CRC value based on a shift length equal to the distance of the unmodified portion to compute a perspective shifted second CRC value by using a fixed number of distance lookup table operations, and generating an updated CRC value from the first CRC value and perspective shifted second CRC value, thereby avoiding recalculating a complete CRC value based on an entirety of the data stream packet.

Abstract: A method and apparatus are provided for computing a CRC value for a packet containing a data stream with a modified data unit data and one or more additional data units extending to the end of the data stream by computing a first CRC value from the one or more additional data units, computing a second CRC value from the modified data unit, adjusting the second CRC value based on a shift length equal to a distance of the one or more additional data units to compute a perspective shifted second CRC value by using fixed number of distance lookup table operations, and generating an updated CRC value from the first CRC value and perspective shifted second CRC value, thereby avoiding recalculating a complete CRC value based on an entirety of the modified data stream.

Abstract: Methods and systems consistent with the present invention store connection information in a memory of a node in a communications network such that the number of searches for retrieving the connection information is less than a predetermined probe threshold. The node includes a hash table and a connection table in the memory for storing and retrieving information associated with packets, frames, and/or cells in the communications network. Each entry in the hash table includes a connection identifier and, for example, a connection index, and is indexed according to a hash value based on the connection identifier. Each entry in the connection table includes connection state information that is indexed according to a connection index in the hash table. To store connection information in the memory, the node identifies in the hash table a first set of addresses that correspond to a first connection identifier.