Subject: [Qirg] Meeting minutes of the weekly QIRG "Architecture Principles for a Quantum Internet" call on Monday 11 November 2019

From: Bruno Rijsman <[email-masked]>
Date: Mon, 11 Nov 2019 13:29:12 +0100

Meeting minutes of the weekly QIRG "Architecture Principles for a Quantum Internet" call
Monday 11 November 2019

Participants:
- Scott Fluhrer
- Daniam Henriques
- Wojciech Kozlowski 
- Eduardo Mas
- Rod van Meter
- Gyananjay Rai
- Bruno Rijsman
- Piotr Rydlichowski

[Wojciech] Provided recap of last call.

All attendees have link to GitHub commits for changes in draft during last week:

- Section 4 updates:
https://github.com/Wojtek242/draft-irtf-qirg-principles/commit/2d54f780ee920c01c698c0d152b7484666def53b

- Section 5 updates:
https://github.com/Wojtek242/draft-irtf-qirg-principles/commit/21e086b1e7387a321594161c69f167783b53eb4b

- Version of draft at the time of the call:
https://github.com/Wojtek242/draft-irtf-qirg-principles/blob/master/draft-irtf-qirg-principles-02.txt

[Rodney] Comments on updates:

- Minor spelling comments

- Add a section 5.4.3 to discuss different error management systems. Need to discuss the different types of errors that can occur in the networks, and the error management mechanisms that can be used to address them.

- Rodney could write something up, but it won't be ready before the Singapore meeting.

- Rodney sent in a long set of comments on the mailing list some weeks ago. Some of those comments have been reflected in the draft, others have not yet need addressed. We need to make sure all comments are eventually addressed. It is okay if some comments lead to a change in the draft, but if so we need to make sure that is a conscious decision.

- We should discuss the 4 roles of quantum repeaters, namely:
(1) Create link-local entanglement.
(2) Create long-distance entanglement. Mainly swapping.
(3) Managing errors. Short term: do nothing or purification. Long term: error correction.
(4) Management of the network. Assessing quality, routing protocols, security, resource management, etc.
Expect the IETF to make important contributions to (4).

- We need to make sure that we attribute the discovery of the no-cloning theory to the correct paper, namely to James Park's 1970 paper.

[Wojciech] What is the standard practice for providing references in IETF documents, as compared to academic papers?

[Bruno] IETF documents have fewer references than academic papers. It is not needed to attribute every idea to its original source. Only provide references that are essential or helpful to understand the document. Need to make a distinction between normative references (that are essential for implementation) and non-normative references.

[Rodney] Must all normative references be IETF standards-track documents?

[Bruno] Not sure.

[Wojciech] Should we add error management to the existing section that discusses distillation, or create a new section? Section 4 is about physical mechanisms, whereas section 5 is about network architecture.

[Rodney?] Create a new section, at the same level as the distillation section.

[Rodney?] We need to mention the different generations of Quantum networks and interoperability between them.

[Bruno] Bruno will contribute the section on MPLS either today or tomorrow (using a Github pull request).

[Wojciech] Summary of the way forward:

- The QIRG working group will meet at the IRTF on Tuesday. The time was chosen to facilitate remote participation from Europe.

- Participants can follow the past changes by looking at the commit history in GitHub and can contribute new material and/or propose changes using GitHub pull requests.

- Wojciech has been careful to reflect all Github activity into the QIRG mailing list.

- The progress until now wraps up the work on back-ground level material in the draft. The basic structure of the document is that section 4 describes the physics of what is going on in the network, whereas section 5 sets the scene for the model of the network.

- We would like to move on to actually describing the goals and the architecture of quantum networks, which are the main topics of the draft.

- We propose to introduce at least one new top-level chapter for this material. (I.e. raise the current section 5.6 "Architectural principles" to a top-level section.)

- This will probably not happen immediately after the IRTF meeting, but eventually.

- As mentioned before, we need to complete addressing the comments that Rodney sent out a week or two ago.

All present agree to this approach.

[Rodney] Does section 5.5 (Physical constraints) in section 5 (Architecture of a quantum internet) or in section (Achieving quantum connectivity )?

[Wojciech] The reason that it is in section 5 is that we first lay out an abstract model, but then we need to point out that in reality the abstract model is constrained by physical reality.

[Wojciech] Section 5.3.1 (Elements of a quantum network) needs more eyes and more discussion. It contains many definitions. Some of these definitions could be contentious. It could be that there are too many things defined, or too few, or that the definitions are wrong. There is also some overlap with Rodneys draft (https://datatracker.ietf.org/doc/draft-van-meter-qirg-quantum-connection-setup/) and we should check whether the definitions are consistent.

[Rodney] We need to check how the current document meshes with all-optical repeaters.

[Rodney] Rodney's group has gone back and forth on how to deal with Bell State Measurement nodes (entanglement stations): whether they should be explicitly modeled as separate nodes in the network, or whether they should be implicit and be considered to be part of the link. The current approach is the latter.

[Wojciech] Agrees. He originally treated them as separate nodes, but now models them as implicitly being part of a quantum link.

[Wojciech] Wojciech would like to draw more interest to the security section. The classical Internet was originally designed with insufficient consideration for security; would like to avoid making the same mistake for the quantum Internet. Wojciech is not aware of any proper investigation of security considerations for Quantum networks (similar to, for example, BGP route origination verification). 

[Rodney] Rodney's group is working on building a taxonomy of elements that are vulnerable to attack in a Quantum network. For example, investigation has shown that if the network is implemented in a naive manner, hijacking a single node allows the attacker to partition the network (essentially using a "smear campaign" that "frames" innocent nodes).

[Wojciech] We need to expand on the security section. We need to not treat this as a formality at the end of the draft, but do a proper investigation of security in Quantum networks.

[Wojciech] Recap of today's meeting:

- We need further updates to the updated sections to reflect comments during this call and on the mailing list.

- Then we will move on to new material on the goals and the architecture of the Quantum internet.

- We will meet and discuss at the QIRG working group meeting at the IRTF in Singapore.