Based on a cascaded double-loop all-optical buffer (DLOB) structure, a new all-optical slot processing scheme is proposed. The all-optical slot processing functions which include slot compressing, slot expanding and slot interchanging or re-aligning, are proved by experiments. The results demonstrate that the interval between two 2.448 Gb/s optical packets can be compressed from 24.3 μs to 110 ns, or expanded from 100 ns to 26.11 μs by two-level DLOB, and the output optical packets have no bit error. The all-optical slot processing scheme proposed in this paper can provide as a reference for all-optical buffer.