QKD Network Demonstration and conference

The first live demonstration of a working quantum key distribution (QKD) network took take place in Vienna between October 8th, 2008 and October 10th, 2008 in the framework of the SECOQC international conference. Seven technologically different QKD-links were combined to form the SECOQC Quantum-Back-Bone network, physically connecting five company sites of SIEMENS Austria in Vienna and the neighbouring capital of Lower Austria, St. Poelten.

We presented the building blocks that are necessary to bring QKD networks to the market. Interfacing with existing business applications were demonstrated for voice telephony and video conferencing, secured by keys distributed over the SECOQC Quantum-Back-Bone network.

Also included in the conference program was the kick-off of the ETSI Industry Specification Group on Quantum Cryptography and Quantum Technologies - an output of the SECOQC standardisation initiative.

The demonstration and the conference were attended by more than 200 people form all over the world - and many more following the live video stram we had for the entire first day. We will put the recording online as soon as we will have it cut and crunched into manageable pieces. Already online we have the SECOQC film, which was produced on the occasion of the project end (See the Documentation Page of the conference site)


A QBB prototype will be demonstrated in Vienna in October 2008 (see city map). A wide range of heterogeneous QKD-systems (“plug & play”, coherent-one-way, one-way, decoy states, entangled photons and continuous variables) engineered by SECOQC partners are connected via Q3P instances to QBB node-modules. The QBB is deployed on a typical telecom metropolitan area ring network. This prototype network will run some well known applications like VoIP or Web Services in an unconditionally secure regime on a 24/7 basis.

City map Vienna. SIEMENS Austria fiber ring network with stations SIE, ERD, GUD, BREIT and “St. Pölten”, connected by QBB-links (© google.com)


The rapid progress in theory and experiment of Quantum Key Distribution (QKD) techniques has been reflected by a number of successful experiments in the past years. Many groups all over the world have put forward QKD-links, operating in the standard point-to-point modus. While a number of research spin-offs entered the market recently (IdQuantique, MagiQ, Smart Quantum), broad proliferation of QKD technology is hindered by a number of road blocks revolving typically around: the inherent limitations of the point-to-point paradigm, the quadratic scaling of necessary initial secrets with the number of users, but also around issues like missing standards.

This EC funded FP6 Integrated Project SECOQC focuses on overcoming these limitations by developing a novel concept of QKD-networks. The project has focused on the trusted repeater paradigm and has developed an architecture allowing seamless integration of heterogeneous QKD-link devices in a unified framework. To this end, network node-modules managing all classical communication tasks are introduced and provide the underlying QKD devices with authentic classical channels. The node–module architecture is based on a layered model allowing to establish network-wide, end-to-end, information-theoretically secure key distribution.

Technical background:

The lower layer realizes a novel Quantum Point-to-Point Protocol (Q3P), which provides standard classical communication interfaces to the QKD devices. Key Stores inside the Q3P protocol-engines take care of the generated secrets, which are used for One-Time-Pad encrypted communication and information-theoretically secure message authentication between adjacent nodes on the upper layers. Q3P allows seamless integration of QKD in modern IT infrastructures.

Although it is possible to run common network protocols like TCP/IP or UDP on top of Q3P, these protocols are not directly appropriate for information-theoretically secure key-agreement. We have therefore implemented two novel protocols, QKD-NL and QKD-TL [2], which allow key-distribution on an end-to-end basis forming the SECOQC Quantum Backbone (QBB).


The SECOQC internal standard for connecting QKD links to node-modules is currently prepared for publication as open standard. In addition, we are launching an Industry Specification Group (ISG) with the European Telecommunication Standards Institute (ETSI) to team important actors from science, industry and commerce to address further standardisation issues in quantum key distribution and quantum technology in general.