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.

中文翻译：

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量子互联网——应用、功能、支持技术、挑战和研究方向


当今世界我们使用的先进笔记本电脑、移动电话和互联网应用程序都根植于经典的零和一通信位。经典互联网的基础源于数学与香农信息论的融合。然而，当今的互联网技术是窃听者的游乐场。这对依赖经典互联网技术的各种应用提出了严峻的挑战，并促使研究人员转向从根本上更安全的新技术。通过探索量子效应，研究人员为量子网络铺平了道路，该网络提供安全性、隐私性以及量子计算、通信和计量等一系列功能。量子互联网（QI）的实现需要通过量子密码协议保护的量子通道在各个远程节点之间进行量子通信。此类网络依赖于可以同时取零和一值的量子位（qubit）。由于量子比特具有叠加、纠缠和隐形传态等非凡特性，它在很多方面都赋予了量子网络相对于传统网络的优势。与此同时，长距离传输量子比特是一项艰巨的任务，基于卫星的量子通信正在进行广泛的研究，这将为在不久的将来物理实现量子量子通信带来突破。本文对 QI 功能、技术、应用和开放挑战进行了广泛调查，以帮助读者对全球 QI 发展所需的基础设施有基本的了解。