The malicious manipulation of quantum key distribution (QKD) hardware is a serious threat to its security, as, typically, neither end users nor QKD manufacturers can validate the integrity of every component of their QKD system in practice. One possible approach to re-establish the security of QKD is to use a redundant number of devices. Following this idea, we address various corruption models of the possibly malicious devices and show that, compared to the most conservative model of active and collaborative corrupted devices, natural assumptions allow to significantly enhance the secret key rate or considerably reduce the necessary resources. Furthermore, we show that, for most practical situations, the resulting finite-size secret key rate is similar to that of the standard scenario assuming trusted devices.

量子密钥分发（QKD）硬件的恶意操作对其安全性构成了严重威胁，因为通常，最终用户和QKD制造商都无法在实践中验证其QKD系统每个组件的完整性。重新建立QKD安全性的一种可能方法是使用冗余数量的设备。遵循这个想法，我们处理了可能的恶意设备的各种损坏模型，并表明，与活动和协作损坏的设备的最保守模型相比，自然假设可以显着提高秘密密钥率或显着减少必要的资源。此外，我们表明，在大多数实际情况下，所得的有限大小秘密密钥率与假设受信任设备的标准方案的结果相似。