BlindTranspiler Documentation
=============================

An open-source framework for rapid prototyping of appication and implementation of protocols using quantum homomorphic encryption universal blind quantum computation.

The library takes in the quantum circuit written in Qiskit and converts with according of various algorithm of Blind Quantum Computation (BQC) primitive, which can be delegated to server by limited capability client on client-server architecture. This delegation ensures the security of the client's data and/or computing algorithm on remote server while execution.

This library enables:

* rapid protocol development for application in secure delegated quantum computation
* experimental with various blindness models
* resource estimation for various blind implementations.
* design and validation of new application for secure quantum cloud computing.
* low-depth and efficient handling of parametric gates, necessary for varitation quantum algorithms.

What is BlindTranspiler?
------------------------

BlindTranspiler is a research-oriented framework for
secure delegated quantum computation.

The library converts standard Qiskit quantum circuits
into blind delegated representations using multiple
blindness models and delegation protocols.


.. image:: _static/lib_outline_funky.png
   :align: center
   :width: 40%



The library can implementation four variations of BQC primitives:

* Quantum Homomorphic Encryption 
* Universal Blind Quantum Computation using Recursive Rotation Gates.
* Universal Blind Quantum Computation using Ordered Set of Universal Gates.
* Universal Blind Quantum Computation using Fixed Rotation Gates.


Why Blind Quantum Computation?
------------------------------

Blind Quantum Computation (BQC) allows a computationally
limited client to delegate quantum computation to a remote
server without revealing:

* input data
* output results
* computation structure
* intermediate operations

Blind delegation is an important primitive for:

* quantum cloud computing
* secure delegated execution
* privacy-preserving quantum machine learning
* outsourced variational quantum algorithms
* secure multi-party quantum computation

BlindTranspiler enables practical experimentation with
these protocols in the NISQ era.
**It natively handles the parametric gates with low-depth circuit**

Getting Started
-----------------

Installation
^^^^^^^^^^^^

Install using PyPI:

.. code-block:: bash

    pip install blind-transpiler

Basic Example
^^^^^^^^^^^^^

Create a Qiskit circuit:

.. code-block:: python

    from qiskit import QuantumCircuit

    qc = QuantumCircuit(3)

    qc.h(0)
    qc.cx(0, 1)
    qc.cx(1, 2)

    qc.measure_all()

.. image:: _static/original_circuit_1.png
   :align: center
   :width: 40%


Perform blind transpilation:

.. code-block:: python

    from blind_transpiler import BQC

    bqc = BQC()

    bqc_instructions = bqc.generate_bqc(qc=qc,format='qhe')

    enc_blind_circ = bqc_instructions.to_circuit(const_type='encrypt_only')

    enc_blind_circ = bqc_instructions.to_circuit(const_type='complete')


The respective output of the circuits when delegated is:

.. list-table::
   :widths: 33 33 33
   :align: center

   * - |img1|

       Fig 1 Expected Output from Original Circuit

     - |img2|

       Fig 2 Output without proper decryption over 1000 random keys

     - |img3|

       Fig 3 Output with proper decryption over 1000 random keys

.. |img1| image:: _static/original_output_1.png
   :width: 90%

.. |img2| image:: _static/qhe_encrypt_only_1.png
   :width: 90%

.. |img3| image:: _static/qhe_complete_1.png
   :width: 90%

This example is elaborated in :doc:`quickstart`

Acknowledgement
---------------

BlindTranspiler is developed as part of ongoing research
into secure delegated quantum computation and practical
blind quantum computing frameworks.

License
-------

BlindTranspiler is released under the Apache 2.0 License.

Documentation Pages
-------------------


.. toctree::
   :maxdepth: 2
   :caption: User Guide

   quickstart
   protocols
   architecture

.. toctree::
   :maxdepth: 2
   :caption: API Reference

   blind_transpiler