Quantum networks are set to play a growing role in the telecommunications sector. One of the challenges is to integrate these disruptive technologies, with their specific features, into current and future digital infrastructures. This is what the team led by Professor Djamal Zeghlache, a lecturer and researcher at Telecom SudParis,is working on .

The rise of the quantum

The application of quantum physics to telecommunications represents a veritable revolution. Quantum communication technologies will provide greater security and protection for data and exchanges. Based primarily on high-speed networks, 5G and then 6G, tomorrow's telecoms networks will naturally incorporate quantum networks. But this integration of highly secure point-to-point optical links into "multipoint-to-multipoint" networks is not going to happen in the blink of an eye.

To achieve this, we first need to master the pillars of these technologies:

- The physical level, corresponding to the communication of signals on an optical medium, with quantum entanglement effects that make it tamper-proof (it is impossible to intercept the signal without disrupting it);

-Quantum sensing and quantum metrology(measurement of states, flows, conditions);

-Calculation and safety aspects .

These potential breakthroughs are the subject of global competition involving both governments and digital giants. European and national funding sources are dedicated to them. The ambition to influence these issues is reflected in the France 2030 plan and in calls for projects linked to sovereignty, managed by the BPI, the DGE and the ANR, such as the Quantum PEPR.

Télécom SudParis and the deployment of quantum technology

The deployment of quantum communications has been the focus of research at Télécom SudParis laboratories for several years, drawing on the funding sources mentioned above and others linked to the evolution of networks, such as PEPR Réseaux du futur.

At Télécom SudParis, we're interested in integrating quantum technologies into existing and future networks," explains Djamal Zeghlache. We're focusing on the interface between current systems and quantum networks, so that the latter can satisfactorily deliver the safety and security properties inherent in them. "

The challenge is to define and optimize these interfaces, taking into account the technical constraints specific to quantum computing, in particular to extend the inviolability provided by this technology. Our work therefore concerns the intelligence of networks and their ability to adapt to remote and distributed quantum users (particularly applications).

One of the objectives is to provide secure, independent and isolated infrastructures, but offered by shared hosting infrastructures. To achieve this, we plan to use Quantum Key Distribution (QKD) , arguably the most advanced technology in the field of quantum communications. This technology enables the exchange of a cryptographic key between two distant parties, based on the principles of quantum physics. It could start to be implemented and deployed within 5 years. The other areas will follow gradually, over the next 10 to 20 years.

Integrating quantum networks into existing networks means adapting the infrastructure control and service management schemes associated with routing schemes, which ensure end-to-end transmission of information in networks. This general scheme includes protocols, routing and switching mechanisms, as well as node and link management. Technically, deploying quantum networks means solving problems of graph extension and modification, and resource allocation.

Beyond the deployment of quantum networks, Télécom SudParis is working on the entire life cycle of networks, their control and management, the modeling of their evolution and the automation of associated functions. This work involves multidisciplinary collaborations with teams from Télécom SudParis, Institut Mines Télécom and other institutions, notably on cross-disciplinary projects.

The innovative algorithmic solutions we can provide to make networks more configurable, interoperable and secure may eventually be transferred to manufacturers," concludes Djamal Zeghlache. In any case, we're working to ensure unimpeded development of these technologies, which are of strategic importance to the country's technological sovereignty ."

Djamal Zeghlache

Professor, Head of Department

RS2M Mobile Multimedia Networks and Services Department

djamal.zeghlache@telecom-sudparis.eu