Membrane fission is a process by which a biological membrane is split into two new ones in the manner
that the content of the initial membrane is separated and distributed between the new membranes. Inspired by this
biological phenomenon, membrane separation rules were considered in membrane computing. In this work, we
investigate cell-like P systems with symport/antiport rules and membrane separation rules from a computational
complexity perspective. Specifically, we establish a limit on the efficiency of such P systems which use communication
rules of length at most two, and we prove the computational efficiency of this kind of models when using
communication rules of length at most three. Hence, a sharp borderline between tractability and NP–hardness
is provided in terms of the length of communication rules.Ministerio de Economía y Competitividad TIN2012-3743
