According to one embodiment, an encryption system (500) includes an input buffer (504) that can provide data blocks from different contexts (522-1 to 522-n) to a selected encryption circuit (524-1 to 524-m) according to a scheduling section (502). A scheduling section (502) can include a register array (510) having rows that each correspond to a context and columns that correspond to an encryption circuit. Each register array (510) row can store one “hot” bit that designates a context with a particular encryption circuit. A column can be selected by a multiplexer (514) and its values prioritized and encoded by a priority encoder (518) to generate an address that results in the selection of a data block from a particular context. Priority may be varied by shifting a column value with a rotate circuit (516) according to an offset value (OFFSET).