Muti-cycle non-parallel data encryption engine

Claim 1

A method for safeguarding data transmissions, comprising the steps of: inputting unencrypted data to a multiplexer; selecting the unencrypted data for input to a first cipher stage of a plurality of cipher stages that are coupled together in series, wherein encryption is performed by each of the cipher stages; feeding back an output from a last cipher stage of the plurality of cipher stages to the multiplexer; selecting the output from the last cipher stage for input to the first cipher stage; cycling through the plurality of cipher stages N times; outputting from one of the plurality of cipher stages a final encrypted data after N cycles have completed.

Claim 2

A method for safeguarding data transmissions, comprising the steps of: inputting unencrypted data to a multiplexer; selecting the unencrypted data for input to a first cipher stage of a plurality of cipher stages that are coupled together in series, wherein encryption is performed by each of the cipher stages; feeding back an output from a last cipher stage of the plurality of cipher stages to the multiplexer; selecting the output from the last cipher stage for input to the first cipher stage; cycling through the plurality of cipher stages N times; outputting from one of the plurality of cipher stages a final encrypted data after N cycles have completed.

Claim 13

An apparatus for encoding or decoding data comprising: an XOR gate for XORing unencrypted data with previously encrypted data; a multiplexer coupled to the XOR gate, wherein the multiplexer selects between an output from the XOR gate and an output from a last cipher block as an input to a first cipher block; a plurality of cipher blocks coupled in series to the multiplexer, wherein the data is encrypted by each of the cipher blocks and encrypted data processed by one cipher block is input to a following cipher block; a feedback path coupled from an output of the last cipher block to an input of the multiplexer, wherein the multiplexer inputs data from the last cipher block to the first cipher block for encryption N cycles through the plurality of cipher blocks; an output register coupled to an output of one of the plurality of cipher blocks for storing the encrypted data.

Claim 14

An apparatus for encoding or decoding data comprising: an XOR gate for XORing unencrypted data with previously encrypted data; a multiplexer coupled to the XOR gate, wherein the multiplexer selects between an output from the XOR gate and an output from a last cipher block as an input to a first cipher block; a plurality of cipher blocks coupled in series to the multiplexer, wherein the data is encrypted by each of the cipher blocks and encrypted data processed by one cipher block is input to a following cipher block; a feedback path coupled from an output of the last cipher block to an input of the multiplexer, wherein the multiplexer inputs data from the last cipher block to the first cipher block for encryption N cycles through the plurality of cipher blocks; an output register coupled to an output of one of the plurality of cipher blocks for storing the encrypted data.

Claim 19

A method of encrypting or decrypting data, comprising the steps of: a) inputting the data to an XOR gate; b) XORing the data with an output from a first cipher stage; c) multiplexing an output from the XOR gate with an output from a third cipher stage; d) storing an output signal from the multiplexer in a register; e) encrypting/decrypting data stored in the register by the first cipher stage to generate a first encrypted/decrypted block of data; f) generating a second encrypted/decrypted block of data by a second cipher stage processing the first encrypted/decrypted block of data; g) generating a third encrypted/decrypted block of data by the third cipher stage processing the second encrypted/decrypted block of data; h) multiplexing an output of the third cipher stage as an input to the first cipher stage; i) repeating steps e-h N times; j) inputting a signal from the third cipher stage after the Nth time and taking the output signal from one of the cipher stages such that the data is encrypted/decrypted through M cycles.

Claim 20

A method of encrypting or decrypting data, comprising the steps of: a) inputting the data to an XOR gate; b) XORing the data with an output from a first cipher stage; c) multiplexing an output from the XOR gate with an output from a third cipher stage; d) storing an output signal from the multiplexer in a register; e) encrypting/decrypting data stored in the register by the first cipher stage to generate a first encrypted/decrypted block of data; f) generating a second encrypted/decrypted block of data by a second cipher stage processing the first encrypted/decrypted block of data; g) generating a third encrypted/decrypted block of data by the third cipher stage processing the second encrypted/decrypted block of data; h) multiplexing an output of the third cipher stage as an input to the first cipher stage; i) repeating steps e-h N times; j) inputting a signal from the third cipher stage after the Nth time and taking the output signal from one of the cipher stages such that the data is encrypted/decrypted through M cycles.