As research in Quantum Key Distribution (QKD) technology grows larger and more complex, the need for highly accurate and scalable simulation technologies becomes important to assess the practical feasibility and foresee difficulties in the practical implementation of theoretical achievements. Due to the specificity of QKD link which requires optical and Internet connection between the network nodes, it is very costly to deploy a complete testbed containing multiple network hosts and links to validate and verify a certain network algorithm or protocol. The network simulators in these circumstances save a lot of money and time in accomplishing such task. A simulation environment offers the creation of complex network topologies, a high degree of control and repeatable experiments, which in turn allows researchers to conduct exactly the same experiments and confirm their results.

The aim of Quantum Key Distribution Network Simulation Module (QKDNetSim) project was not to develop the entire simulator from scratch but to develop the QKD simulation module in some of the already existing well-proven simulators. QKDNetSim is intended to facilitate additional understanding of QKD technology with respect to the existing network solutions. It seeks to serve as the natural playground for taking the further steps into this research direction (even towards practical exploitation in subsequent projects or product design).

QKDNetSim implements the full functional Key Management System (KMS) with key-relay functionality supporting ETSI GS QKD 014 and ETSI GS QKD 004 key delivery interfaces.

The detailed documentation is available on webpage https://www.qkdnetsim.info

• The latest version of the code is compatible with NS-3 version 3.46.
• Thus, one should follow installation requirements from the NS-3 official website (https://www.nsnam.org/wiki/Installation).
• The code has been successfully tested on Ubuntu 22.04.
• QKDNetSim v2.0 module is NOT compatible with QKDNetSim version 1.0 (https://v1.qkdnetsim.info). QKDNetSim v2.0 module was written independently and from scratch.

QKDNetSim includes QKDEncryptor class that relies on cryptographic algorithms and schemes from Crypto++ open-source C++ class cryptographic library. Currently, QKD crypto supports several cryptographic algorithms and cryptographic hashes, including One-Time Pad (OTP) cipher, Advanced Encryption Standard (AES) block cipher, VMAC message authentication code (MAC) algorithm, and others.

1. Install prerequisites libreries:

   sudo apt-get install gcc g++ python3 python3-dev mercurial bzr gdb valgrind gsl-bin doxygen graphviz imagemagick -y  && \
   sudo apt-get install libboost-all-dev git flex bison tcpdump sqlite sqlite3 -y   && \
   sudo apt-get install libsqlite3-dev libxml2 libxml2-dev libgtk2.0-0 libgtk2.0-dev uncrustify -y  && \
   sudo apt-get install libcrypto++-dev libcrypto++-doc libcrypto++-utils unzip wget uuid-dev cmake -y

2. Install the NS-3 of version 3.46 from the

   git clone -b ns-3.46 https://gitlab.com/nsnam/ns-3-dev.git

3. Download qkdnetsim in contrib directory

   cd ns-3-dev/contrib
   git clone -b master https://github.com/QKDNetSim/qkdnetsim

4. Check patches. They should report no error

   cd ..
   git apply --check contrib/qkdnetsim/patches/gnuplot_cc.patches
   git apply --check contrib/qkdnetsim/patches/gnuplot_h.patches

5. Apply patches

   git apply  contrib/qkdnetsim/patches/gnuplot_h.patches
   git apply  contrib/qkdnetsim/patches/gnuplot_cc.patches

6. Configure NS-3 with qkdnetsim

   ./ns3 configure --enable-mpi --enable-examples

7. Run qkdnetsim examples

   ./ns3 run examples_qkdnetsim_etsi_014
   ./ns3 run examples_qkdnetsim_etsi_004
   ./ns3 run examples_qkdnetsim_secoqc
   ./ns3 run examples_qkdnetsim_etsi_combined_input
   ./ns3 run examples_qkdnetsim_etsi_014_emulation_tap

QKDNetSim is maintained by:

• Department of Telecommunications (www.tk.etf.unsa.ba)
  Faculty of Electrical Engineering
  University of Sarajevo
  Zmaja od Bosne bb
  71000 Sarajevo
  Bosnia and Herzegovina
• Department of Telecommunications (www.comtech.vsb.cz) VSB Technical University of Ostrava
  17 . listopadu 15/2172
  Ostrava-Poruba 708 33
  Czech Republic

Main developers:

• Emir Dervisevic
• Miroslav Voznak
• Miralem Mehic

Contact us via email (miralem[at]mehic.info).

• Dervisevic, E., Voznak, M. and Mehic, M., 2024. Large-Scale Quantum Key Distribution Network Simulator. Journal of Optical Communications and Networking, doi: https://www.doi.org/10.1364/JOCN.503356
• Dervisevic, E., Tankovic, A., Kaljic, E., Voznak, M. and Mehic, M., 2025. Design of a Key Management System for Efficient Key Supply in Quantum Key Distribution Networks. Journal of Optical Communications and Networking, doi: https://www.doi.org/10.1364/JOCN.577670
• Dervisevic, E., Tankovic, A., Fazel, E., Kompella, R., Fazio, P., Voznak, M. and Mehic, M., 2025. Quantum Key Distribution Networks – Key Management: A Survey. ACM Computing Surveys, 57(10), pp. 1–36, doi: https://www.doi.org/10.1145/3730575
• Mehic, M., Dervisevic, E., Burdiak, P., Lipovac, V., Fazio, P. and Voznak, M., 2024. Emulation of quantum key distribution networks. IEEE Network, 39(1), pp.116-123. doi: https://www.doi.org/10.1109/MNET.2024.3398404
• Mehic, M., Dervisevic, E., Fazio, P. and Voznak, M., 2025. Virtual Quantum Key Distribution Network Ecosystem: The National Czech QKD Network. IEEE Network., 39(3), pp.173-179. doi: https://www.doi.org/10.1109/MNET.2025.3540705

Development of QKDNetSim was supporty within projects #VJ01010008 “Network Cybersecurity in Post-Quantum Era” by the Ministry of the Interior of Czech Republic in program Impakt, Ministry of Science, Higher Education and Youth of Canton Sarajevo, Bosnia and Herzegovina (27-02-35-37082-1/23), NATO SPS G5894 project ”Quantum Cybersecurity in 5G Networks (QUANTUM5)” and H2020 project OPENQKD (No. 857156).