Impact of packet size variation in overlay quantum key distribution network

Quantum Key Distribution (QKD), based on the laws of physics rather than the computational complexity of mathematical problems, provides an information-theoretically secure way of establishing symmetrical binary keys between two geographically distant users. This paper is oriented to the practical realization of QKD public channels which are usually implemented as overlay point-to-point connections. We address the problem of minimizing the key material consumption by changing packet overhead. Our results show that the efficiency of communication in overlay QKD networks may increase when packets of larger sizes are used. However, this tuning directly affects the performance of overall communication. We evaluated this approach using an overlay network module which was implemented in the NS-3 simulator. The obtained results can be used for other overlay networks as well.