Patent ID: 6775274
Filing Date: 2004-08-10
Classification: H04L

Abstract:
A secure communication circuit for use with a data communication interconnect adapter, the secure communication circuit comprising:a first data buffer coupled between a data input terminal and a switching device, the switching device coupled between the first data buffer and a data output terminal; an encoder/decoder coupled between the first data buffer and a second data buffer, the second data buffer coupled between the encoder/decoder and the switching device, the first data buffer coupled between the data input terminal and the encoder/decoder, the encoder/decoder being capable of encrypting/decrypting data, wherein the data is a data frame, the data frame including a frame header, the frame header including a start of frame (SOF) indicator, a source address and a destination address, and a cyclic redundancy check (CRC) data, the data frame also including a payload data and an end of frame (EOF) determinator, and wherein only the data frame is the secure communication, such that the frame header and EOF determinator are transmitted without encoding, and the payload data is transmitted encoded; and a controller, coupled to the switching device, that selectively connects the switching device to the first or second data buffers, such that the switching device, under the direction of the controller, passes unencrypted data directly from the first data buffer to the data output terminal, and the switching device passes encrypted data from the second data buffer to the data output terminal.