The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.
This example protocol implements the functionality of Quantum Encryption with Certified Deletion using single-qubit state preparation and measurement.
Assumptions
Outline
The scheme consists of 5 circuits-
- Key: This circuit generates the key used in later stages
- Enc: This circuit encrypts the message using the key
- Dec: This circuit decrypts the ciphertext using the key and generates an error flag bit
- Del: This circuit deletes the ciphertext state and generates a deletion certificate
- Ver: This circuit verifies the validity of the deletion certificate using the key
Notation
Properties
Protocol Description
Circuit 1: Key
The key generation circuit
Input : None
Output: A key state
- Sample
- Sample where
- Sample
- Sample
- Sample
- Sample
- Sample
- Output
Circuit 2: Enc
The encryption circuit
Input : A plaintext state and a key state
Output: A ciphertext state
- Sample where
- Compute where
- Compute
- Compute
- Output
Circuit 3: Dec
The decryption circuit
Input : A key state and a ciphertext
Output: A plaintext state and an error flag
- Compute
- Measure in the computational basis. Call the result
- Compute where
- Compute
- If , then set . Else, set
- Compute
- Output
Circuit 4: Del
The deletion circuit
Input : A ciphertext
Output: A certificate string
- Measure in the Hadamard basis. Call the output y.
- Output
Circuit 5: Ver
The verification circuit
Input : A key state and a certificate string
Output: A bit
- Compute where
- Compute
- If , output . Else, output .
Further Information
References