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. But today's internet technology is a playground for eavesdroppers. This poses a serious challenge to various applications that relies on classical internet technology. This has motivated the researchers to switch to new technologies that are fundamentally more secure. 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 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 extraordinary properties of qubits such as entanglement, teleportation and superposition, it gives an edge to quantum networks over traditional networks in many ways. But at the same time transmitting qubits over long distances is a formidable task and extensive research is going on quantum teleportation over such distances, which will become a breakthrough in physically realizing quantum internet in near future. In this paper, quantum internet functionalities, technologies, applications and open challenges have been extensively surveyed to help readers gain a basic understanding of infrastructure required for the development of global quantum internet.

翻译：在当今世界上,我们使用的先进笔记本、移动电话和互联网应用都植根于经典通信零位和零位的零位和计量学。古典互联网已经从数学和克洛德·香农信息理论的结合中打下了基础。但今天的互联网技术是偷听者的一个游乐场。这对依赖古典互联网技术的各种应用构成了严重挑战。这促使研究人员转向基本更加安全的新技术。探索量子效应,研究人员为量子网络铺平了道路,提供了安全、隐私和量子计算、通信和计量学等一系列能力。实现量子互联网需要通过量子加密协议保护的量子频道进行量子通信。这种网络依赖于量子比(Qbits),可以同时使用零和零值的价值。由于昆虫的特殊性,它使得量子网络以多种方式超越传统网络的优势。但与此同时,长距离传输量子网络是一项艰巨的任务,通过量子频道在量子加密协议的量子频道之间进行量子通信通信通信通信通信。这类网络技术的突破性研究将使得互联网在纸质学上实现一个开放的突破。