Patent ID: 8233619

Claim:
At least one circuit for encrypting at least a part of an input data flow and generating a tag based on said input data flow with a same ciphering algorithm and a same key, said at least one circuit comprising a pipeline comprising: an input selection unit arranged to receive and to select one of: first input data for generating encryption sequences with said ciphering algorithm; second input data for generating temporary tags with said ciphering algorithm; and output data of the pipeline; a first stage comprising a first temporary storage element configured to receive an output of said input selection unit and at least a first operation unit; and a second stage comprising a second temporary storage element configured to receive an output of the first stage and at least a second operation unit and providing said output data of the pipeline, the first and second stages performing iterative computations of the ciphering algorithm, one or more operation units of the first and second stages being activated only in selected rounds of the iterative computations, the first and second stages of the pipeline, on successive rounds of the iterative computations, alternating between generating encryption sequences with said ciphering algorithm and generating the tag for data integrity, wherein common circuitry in the pipeline generates encryption sequences with said ciphering algorithm and generates the tag for data integrity on successive rounds of the iterative computations.