  Multipartite quantum entanglement serves as a resource for spatially
separated parties performing distributed quantum information processing. Any
multipartite entangled state can be generated from appropriately distributed
bipartite entangled states by local operations and classical communication
(LOCC), and in this sense, any distributed process based on shared multipartite
entanglement and LOCC is simulatable by using only bipartite entangled states
and LOCC. We show here that this reduction scenario does not hold when there
exists a limitation on the size of the local quantum system of each party.
Under such a limitation, we prove that there exists a set of multipartite
quantum states such that these states in the set cannot be prepared from any
distribution of bipartite entanglement while the states can be prepared from a
common resource state exhibiting multipartite entanglement. We also show that
temporal uses of bipartite quantum communication resources within a limitation
of local system sizes are sufficient for preparing this common resource state
exhibiting multipartite entanglement, yet there also exist other states
exhibiting multipartite entanglement which cannot be prepared even in this
setting. Hence, when the local quantum system sizes are limited, multipartite
entanglement is an indispensable resource without which certain processes still
cannot be accomplished.
