ABSTRACT
This chapter highlights quantum technology protocols or devices that will be the critical core components of the future quantum network. A good place to start is with a discussion of quantum random-number generators— no quantum internet is complete without one! To be called quantum technology, a technology must exploit at least one of the three features that Einstein disliked about quantum theory: quantum uncertainty, quantum unreality, and quantum nonlocality. There are quite a number of quantum cryptography protocols, the chapter focuses on the two in everyday use. The first is BB84, invented by Bennett and Brassard in 1984. It uses the first two ingredients of quantum technology but not quantum entanglement. The second is the E91 protocol invented by Ekert in 1991. The future quantum internet will allow all users (nodes) to share entanglement with any other user on the network. The chapter provides the fundamental protocols that are necessary to make that happen.
