The Quantum Internet - i.e. an heterogeneous network enabling quantum communications among remote quantum nodes by leveraging on quantum transmission channels in synergy with classical transmission channels - is attracting worldwide academic and industrial interest [1, 2, 3, 4, 5, 6, 7], given its potential of enabling applications with no counterpart in the classical Internet [8]. Indeed, the Quantum Internet, by transmitting qubits and by distributing entangled quantum states, comes with a whole new dazzling functionalities [9, 10].
The Quantum Internet - i.e. an heterogeneous network enabling quantum communications among remote quantum nodes by leveraging on quantum transmission channels in synergy with classical transmission channels - is attracting worldwide academic and industrial interest [1, 2, 3, 4, 5, 6, 7], given its potential of enabling applications with no counterpart in the classical Internet [8]. Indeed, the Quantum Internet, by transmitting qubits and by distributing entangled quantum states, comes with a whole new dazzling functionalities [9, 10].
The Quantum Internet represents a paradigm shift in communication technology, leveraging quantum mechanical principles such as superposition, entanglement, and the no-cloning theorem to enable ultra-secure, high-fidelity, and potentially revolutionary global connectivity. Unlike the classical internet, which transmits bits through electromagnetic signals, the Quantum Internet transmits qubits, allowing the creation of unbreakable cryptographic channels, distributed quantum computation, and quantum-enhanced sensing networks. This paper presents a comprehensive review of the Quantum Internet, covering its underlying principles, layered architecture, enabling hardware technologies, and core communication protocols. We analyze current and emerging applications, from secure government and financial communications to healthcare and fundamental physics experiments. The study highlights the unique advantages of quantum networking, such as intrinsic security against eavesdropping, global-scale entanglement distribution, and integration with distributed computing infrastructures. At the same time, it addresses practical limitations, including distance constraints, quantum memory coherence times, infrastructure costs, and security risks associated with hardware vulnerabilities. Special attention is given to the feasibility of large-scale deployment in India, leveraging national programs such as NM-QTA and QuEST, as well as satellite-based quantum communication initiatives by ISRO. The paper concludes with a roadmap for the realization of a global quantum network, identifying technical, infrastructural, and policy challenges that must be addressed in the coming decades.
The advanced notebooks, mobile phones, and internet applications in today’s world that we use are all entrenched in classical communication bits of zeros and ones. Classical internet has laid its foundation originating from the amalgamation of mathematics and Claude Shannon’s theory of information. However, today’s internet technology is a playground for eavesdroppers. This poses a serious challenge to various applications that rely on classical internet technology, and it has motivated the researchers to switch to new technologies that are fundamentally more secure. By exploring the quantum effects, researchers paved the way into quantum networks that provide security, privacy, and range of capabilities such as quantum computation, communication, and metrology. The realization of Quantum Internet (QI) requires quantum communication between various remote nodes through quantum channels guarded by quantum cryptographic protocols. Such networks rely upon quantum bits (qubits) that can simultaneously take the value of zeros and ones. Due to the extraordinary properties of qubits such as superposition, entanglement, and teleportation, it gives an edge to quantum networks over traditional networks in many ways. At the same time, transmitting qubits over long distances is a formidable task and extensive research is going on satellite-based quantum communication, which will deliver breakthroughs for physically realizing QI in near future. In this paper, QI functionalities, technologies, applications and open challenges have been extensively surveyed to help readers gain a basic understanding of the infrastructure required for the development of the global QI.
The Quantum Internet, a network interconnecting remote quantum devices through quantum links in synergy with classical ones, is envisioned as the final stage of the quantum revolution, opening fundamentally new communications and computing capabilities. But the Quantum Internet is governed by the laws of quantum mechanics. Phenomena with no counterpart in classical networks, such as no-cloning, quantum measurement, entanglement and quantum teleportation, impose new challenging constraints for network design. Specifically, classical network functionalities are based on the assumption that classical information can be safely read and copied. However, this assumption does not hold in the Quantum Internet. As a consequence, its design requires a major network-paradigm shift to harness the quantum mechanics specificities. The goal of this work is to shed light on the challenges and open problems of Quantum Internet design. We first introduce some basic knowledge of quantum mechanics, needed to understand the differences between a classical and a quantum network. Then, we introduce quantum teleportation as the key strategy for transmitting quantum information without physically transferring the particle that stores the quantum information or violating the principles of quantum mechanics. Finally, the key research challenges to design quantum communication networks are discussed.
As quantum computers advance rapidly, traditional encryption methods are becoming vulnerable, making it essential to explore fundamentally new communication technologies such as the quantum internet. The quantum internet is a revolutionary technology that uses the principles of quantum mechanics to transmit data securely and quickly. Unlike classical networks, quantum networks use quantum entanglement and quantum key sharing (QKD), thus providing a higher level of security against future cyber threats. This article presents the technological foundations of the quantum internet, the architecture of quantum networks, and the infrastructure challenges, including quantum repeaters and network scaling. We also discuss industrial applications of the quantum internet, with a focus on the financial, government, and healthcare sectors. The quantum internet is still under development, but it is expected to become a new standard for communication in the coming decades. The study highlights the technological readiness and practical potential of the quantum internet, pointing to a secure and scalable future in communication networks.
The stages of a quantum internet As indispensable as the internet has become in our daily lives, it still has many shortcomings, not least of which is that communication can be intercepted and information stolen. If, however, the internet attained the capability of transmitting quantum information—qubits—many of these security concerns would be addressed. Wehner et al. review what it will take to achieve this so-called quantum internet and propose stages of development that each correspond to increasingly powerful applications. Although a full-blown quantum internet, with functional quantum computers as nodes connected through quantum communication channels, is still some ways away, the first long-range quantum networks are already being planned. Science , this issue p. eaam9288
Quantum networks play a pivotal role in quantum information science, which not only provide a secure communication platform for remote access to quantum computers but also serve as the strategic core for achieving large-scale quantum information processing, forming the foundational infrastructure for the future global-scale quantum internet. Quantum teleportation, which enables the transmission of unknown quantum states over long distances by employing quantum entanglement together with classical communication, is essential for the distribution of quantum resources in the construction of the global-scale quantum internet. To realize a global-scale quantum internet, quantum repeater protocols represent one of the most promising approaches for enabling quantum communication between any nodes. This concise review presents representative experimental demonstrations of quantum teleportation for constructing quantum networks across different physical platforms. Along this trajectory, the review discusses current challenges, open issues, and future perspectives toward scalable and practical quantum internet.