Figure 1.

Figure 2.

Figure 3.

Figure 4.

Figure 5.

Figure 6.

Comparison with other QNC schemes_
| QNC scheme | Quantum resources | Possibility to be used in QKD | Relationship between key rate and transmittance |
|---|---|---|---|
| XQQ [2] | Non-orthogonal quantum states | No | - |
| QNC based on PE scheme [3,6,12] | Pre-shared entanglements | Possible | R ∝ η |
| QNC with repeaters [11] | Quantum repeaters | Possible | R ∝ η1/n |
| QNC based on MBQC [5,9] | Cluster states | No | - |
| Our scheme | Weak coherent states | Yes | R ∝ η1/2 |
Comparison of channel usage between TF-QNC and TF-QKD_
| Scheme | Non-bottleneck channels | Bottleneck channel | Average total times |
|---|---|---|---|
| Point-to-Point TF-QKD | 2 channels × 2 | 2 | 6n1 |
| Point-to-Point TF-QNC1 | 2 channels × 2 | 1 | |
| Multi-Party TF-QKD2 | 4 channels × 6 | 4 | 28n2 |
| Multi-Party TF-QNC | 4 channels × 2 | 1 | 9γn2 |
Comparison of quantum states usage between TF-QNC and TF-QKD_
| Scheme | Quantum states in one execution | Average total number |
|---|---|---|
| Point-to-Point TF-QKD | 2 nodes × 1 | 2n1 |
| Point-to-Point TF-QNC | 2 nodes × 1 | |
| Multi-Party TF-QKD | 4 nodes ×3 | 12n2 |
| Multi-Party TF-QNC | 4 nodes × 1 | 4γn2 |