Fig. 3
From: Private quantum computation: an introduction to blind quantum computing and related protocols
a An illustration of the BQC setting considered by Childs.27 In this scenario, the client has a large quantum memory together with the ability to perform Pauli operations on qubits and to transmit them to the server. However they lack the ability to perform other gates, such as Toffoli or Hadamard gates. b An illustration of the setting considered by Aharonov, Ben-Or and Eban,12 in which the client has access to a quantum computer capable of performing arbitrary operations on a constant number of qubits
