Day 1
What is quantum communication about?
Qubit and quantum register
IBM Quantum
How to prepare a superposition?
- Preparing an arbitrary quantum state
No cloning theorem
- No Cloning Theorem - Proof
Entanglement
- Decomposition exercise
- Entangled states
- Difference between product and entangled states
- What does entanglement mean?
- Famous entanglement pairs
- How to produce entangled pairs?
- Changing the bases of an entangled pair
- CNOT gate
- Bell state generator
- Generalized quantum entangler
- How to create entangled qubits physically? - An example
Implementation examples for qubits
- Physical qubits
- Di Vincenzo criteria
- Superconducting qubits
- Trapped ions
- Photonic qubits
Day 2
Quantum key distribution over optical fiber
- From theory to the real world
- Protocol stack of QKD
Two important quantum communication protocols
- Quantum Communication – the players
- Superdense coding
- Teleportation
- Superdense coding and Teleportation
Quantum Medium Access Control
- Medium Access Control in distributed environment - quantum WIFI
- Quantum WIFI - MAC
- Quantum MAC - JOIN
- Quantum MAC - LEAVE
- Quantum MAC - TRANSFER
- Quantum MAC - generalization
- Rebalacing
- Quantum periodic table
Density matrix and its application in quantum communications
- Decomposition exercise
- Introduction to density matrix formalism
- Calculation of density matrices
- Mixed states
- Geometrical representation
- Are density matrices unique?
- Partial trace
- Postulates with density matrices
- Teleportation
- State vs. density matrix formalisms
Why do we need quantum key distribution?
- Problem formulation
- Symmetric Keys
- Symmetric Keys – problems and solutions
- Asymmetric Key System
- Problem formulation
- Problem formulation – Quantum Key Distribution
Quantum key distribution approaches
- Two types of QKD
- In real life, quantum channel is not ideal
- BB84, the first QKD protocol
- SARG04 protocols
- B92 protocol
- Entanglement based QKD
- E91 protocol
Passive and active attacks
- Passive attack
- Active attack
- Attack types
- Denial of service attack
- Man-in-the-middle attack
Day 3
Non idealistic channels
- Why realistic quantum channels are important?
- General model of communication
- AWGN
- Channel capacity
- A suprising example
- Various quantum capacities
- Basic quantum channel models
- Effects in real fibers
Interesting QKD approaches
- Chicago Quantum Exchange
- Chinese Quantum Network: More than 4600 kilometers
- UK Quantum Communications Hub
- EuroQCI
- Companies: ID Quantique
- Companies: MagiQ
- Companies: Quintessence Labs
Technical study: implementing BB84
- High level overview
- Physical realization
Quantum key distribution via free-space
- Why to use free-space instead of fiber-based solution?
Errors in free-space quantum channels
- Quantum signals on free-space channels
- There are equations behind everything
- But this is what is important
Prepare-and-measure QKD vs entanglement-based QKD
- Prepare-and-measure QKD -advantages
- Prepare-and-measure QKD -disadvantages
- Entanglement-based QKD -advantages
- Entanglement-based QKD -disadvantages
Physical attacks on quantum key distribution protocols
- Intercept and resend
- Faked states attack
- Photon number splitting attack
- Trojan Horse Attack (Light Injection Attack)
- Using a beam splitter
Interesting free-space QKD approaches
- Scenarios for satellite based quantum communicatoins
- How to use an entanglement-based satellite system?
- Quantum Experiments at Space Scale (QUESS)
- Singapore’s mission in 2019
- SpooQy 1
- European answer: SAGA
- A draft concept of the European SAGA system
- Timeline for the SpaceQCI (from European Comission)
- Timeline for the SAGA mission (from ESA)
- Security threats to a satellite QKD system
Quantum Secure Network, Quantum Information Network
- Stages to achieve a global quantum internet
Ingredients of future's quantum internet
- Challenges
- Entanglement swapping
- Entanglement swapping - remarks
- Routing
Overview of standardization
- Working on standards
- Working on quantum communications standards
- ETSI Quantum-Safe Cryptography (QSC) working group
- ETSI - Quantum-Safe Cryptography (QSC)
- ETSI Industry Specification Group (ISG)
- ETSI QKD
- ETSI Standards – An example
- IETF QIRG – Standards for quantum internet
- IETF QIRG – Two dradts
Quantum communication: implementation challenges
- Technical study: implementing CV-QKD system
A Hungarian CV-QKD system
- Technical study: implementing quantum random number generator (QRNG)
The simplest QRNG
Summary and outlook
- Future's satellite system
- QKD and autonomous vehicles
- QKD and 5G
