I am not an internet connectivity tech. & not formally educated regarding quantum computing. You may wish to follow along with my thoughts below: partly basic quantum internet info. I searched out & share here, & partly my own personal opinions & conclusions. Your own thinking & conclusions are also necessary. Hopefully I can save you some time by sending some of your thoughts in helpful directions & towards useful questions.

What. Quantum internet, for beginners: It’s to be “the next generation of WWW”; a co-existent network in addition to the current WWW. & A  “network of interconnected quantum computers that will one day allow people to send, compute, & receive information using quantum technology”. Oh. & We are not likely to own personal quantum computers soon ourselves. Might still sound mysterious to you & me. Let’s learn some basics together. To be a bit more educated about future global connectivity. 

What can quantum internet do?: Like many developing sciences, we don’t know full implications; might not know for some time; won’t understand everything a quantum internet can do “until it’s been fully developed”. We are told: likely to have awesome capabilities. Is believed it will be used to solve specific types of problems. Example: providing “quantum cryptography” (think: secure info.). Because it will “send, compute, & receive info. encoded in quantum states“. & Will be utilized via quantum cloud computing. “Several applications have been theorized”. & Some applications … are already in use (notably in finance; banking). 

Why a quantum internet?: Suggested advantages include:

1.  (Multiple mentions of) capability to send data much more securely. Although there are already warnings that even a fully quantum internet might eventually fall prey to attacks “themselves quantum based”. For now (per current working theory & experience) we envision unhackable (ultra-secure, encrypted) communications. Because “a hacker can’t tamper… without leaving behind a telltale sign”.

2. Quantum computers joined via a quantum internet, “their computational power pooled”, may = far greater capabilities. E.g. of this idea: last year 2023, Microsoft [apparently said] “it is working on a topological quantum computer… with the aim of arriving within 10 years at a computer capable of carrying out at least one million operations per second with an error rate of one operation in every 1,000 billion”.

3.  “Particularly useful for problems [with] many variables”. Some examples: “analyzing financial risk, encrypting data, & studying the properties of materials”. 

When a quantum internet?: We aren’t there yet. Some have estimated that “interstate quantum networks will be established within the U.S. in the next ~ dozen years”. No one has yet successfully created “a sustained quantum network on a large scale, but there have been major advances.” In June 2022 a Chicago network was “one of the longest [in U.S.] …124 miles of optical fiber—transmitting … quantum-encoded information between 3 buildings.” 

Some next steps: There is “possibility of using satellites to form part of a quantum network”. & We need quantum repeaters in order to transmit info. in quantum form over long(er) distances. “Researchers have demonstrated… [possible] to build such repeaters, but [as of 2019…] they haven’t yet … produced a working prototype.”  In addition, researchers around the World are racing to create more secure quantum teleportation networks, for even further communications security.

We need a method to detect “when a quantum signal is ready to be retrieved, without destroying the properties of the signal, …[paving] the way for quantum repeaters [which would] extend the range of a quantum signal”. Because this would be a key step towards a large-scale quantum internet.

Recent (quantum memory) breakthrough: “Quantum networks… [have] needed to be cooled to absolute zero to operate…” limiting their large scale practicality. Just last month (Feb. 2024) a breakthrough: “a new technique in quantum storage that [for the first time] operates at room temp. could pave the way for a quantum internet.” Making us another step closer to a quantum internet.