is a topic of great importance, both
theoretically and practically, in its own
right irrespective of whether it is used
in a cryptographic setting or not.
22 Another method to achieve verification
of quantum computation in the post-quantum computational security setting, which does not necessarily rely in
hiding the computation, was proposed
In Cojocaru et al.,
15 a quantum channel is replaced by a functionality of delegated pseudo-secret random qubit
generator. Communicating random
(secret) qubits is the only quantum
communication required in many protocols (for example, Broadbent et al.
and Fitzsimons et al.
20). The key idea to
achieve this functionality is to instruct
the server to generate a state where
some qubits are entangled, while some
are unentangled. This is done in such
a way that the connectivity is known
to the client (that has access to trap-door information) but is unknown to
the server (that does not have access).
The client uses this advantage and instructs the server to prepare an output
qubit in a random state, of which the
client knows its classical description
while the server is totally ignorant. This
exactly mimics a random single-qubit
The ability to communicate securely
and compute efficiently is more important than ever to society. The Internet and increasingly the Internet
of Things, has had a revolutionary
impact on our world. Over the next
5–10 years, we will see a flux of new
possibilities, as quantum technologies become part of this mainstream
computing and communicating
landscape. Future networks will certainly consist of both classical and
quantum devices and links, some
of which are expected to be dishonest, with functionalities of various
sophistication, ranging from simple
routers to servers executing universal quantum algorithms (see Figure
3). The realization of such a complex
network of classical and quantum
communication must rely on a solid
novel foundation that, nevertheless,
is able to foresee and handle the in-tricacies of real-life implementations
and novel applications.
While post-quantum security paves
the way for our classical Internet to
remain safe in that era, quantum enhanced security aims to benefit actively
from the development of quantum Internet in order to achieve unparalleled
performances that are provably impossible using classical communication.
Meanwhile quantum cloud services
with various capabilities are becoming
available. Quantum enabled security
provides the platform that will ensure
potential users that this new, unprecedented computational power in the
quantum cloud, comes with the appropriate standards of accuracy, reliability
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Petros Wallden ( firstname.lastname@example.org) is Lecturer at
the University of Edinburgh, Scotland, U.K.
Elham Kashefi ( email@example.com) is a
professor at the University of Edinburgh, Scotland,
U.K. and Sorbonne Université, CNRS, Laboratoire
d’Informatique de Paris, France.
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