Minutes IETF109: qirg
minutes-109-qirg-00

MEETING MINUTES
===============

IETF 109 (online)
Quantum Internet Research Group (QIRG)
Monday 16 November

(1) Agenda bashing
------------------

(2) Status of the research group
--------------------------------

- The USA department of energy announced the Quantum Internet blueprint:
  https://www.energy.gov/sites/prod/files/2020/07/f76/QuantumWkshpRpt20FINAL_Nav_0.pdf

- Wojciech Kozlowski and Rodney van Meter wrote blog post to promote QIRG
  working group: https://www.ietf.org/blog/quantum-internet/

- The principles draft is basically ready for last call; this will be discussed
  in this meeting.

- The use cases draft is almost ready for last call as well.

- There are three expired drafts: we need to determine whether to pick them up
  again (there is still interest in them):

- Proposal for next steps:
  - Focus on education (e.g. talks)
  - We might shift to fewer IETF meetings and more (shorter) interim meetings
  - Keep working on drafts

(3) Presentation on "Measurement Device Independent (MDI) Quantum Key
Distribution (QKD)" by Joshua Slater
----------------------------------------------------------------------------------------------------------

- Slides at
  https://datatracker.ietf.org/meeting/109/materials/slides-109-qirg-mdi-qkd-quantum-internet-00

- Questions and comments:

- Bruno Rijsman: Can you explain why we need QKD (or PQC) to replace classical
  PKI in the first place? Josh Slater: The danger of Shor's algorithm breaking
  public key infrastructure (PKI) once we have sufficiently large quantum
  computers.

- Rodney van Meter: How long are the links that QuTech is installing in the 4
  node quantum network? Josh Slater: Only the 1st fiber has been installed, it
  has 20 dB loss. The loss for the other 3 links is not yet known. Fibers are
  never straight-line and always have connection points that cause extra loss.

- Shota Nagayama: Do QKD networks have end-to-end conventional keys? Josh
  Slater: QKD networks securely generate end-to-end conventional keys.

- Shota Nagayama: Does QKD need trusted intermediate nodes? Josh Slater: The
  MDI QKD middle node does not need to be trusted [see also question from
  Kireeti Kompella later on].

- Philip Hallam-Baker: What about traffic analysis attacks? Josh Slater: An
  attacker can see when keys are generated, but cannot know the keys values or
  when the keys are actually used to encrypt.

(4) Status and recent updates on the use cases draft by Chonggang Wang
----------------------------------------------------------------------

- "Applications and Use Cases for the Quantum Internet" draft at
  https://www.ietf.org/archive/id/draft-irtf-qirg-quantum-internet-use-cases-03.txt

- Presentation slides at
  https://datatracker.ietf.org/meeting/109/materials/slides-109-qirg-draft-irtf-qirg-quantum-internet-use-cases-01

- Questions and comments:

- Wojciech Kozlowski: I am still confused about quantum control plane versus
  data plane. It's clear for classical networks, but what does it mean for
  quantum networks? Chonggang Wang: Discusses table (figure 1) in the use cases
  draft. The data plane is actual user traffic, the control plane is not actual
  user traffic but facilitates user traffic exchange. The control traffic may
  be classical (e.g. setup protocols) or quantum (e.g. quantum ping).

- Michelle Victoria: Is the goal of the use cases document to guide the layman
  (rather than the quantum expert)? Chonggang Wang: There are two purposes. The
  document is intended for those who are interested to gain a high-level
  overview of applications before diving into the details. It is intended as
  starting point for later more detailed standards documents. Wojciech
  Kozlowski: It is intended for classical networking experts, not for complete
  laymen.

- Michelle Victoria: Should the draft include examples of benefits gained from
  distributed quantum computing? Chonggang Wang: Yes, it would be good to
  include some benefits in the next version. Wojciech Kozlowski: I provided
  similar feedback by e-mail.

- Rodney van Meter: Suggestion to merge last two columns in figure 1 into a
  single column.

- Chonggang Wang: Is document ready for last call? Wojciech Kozlowski + Rodney
  van Meter + Bruno Rijsman: Think it will be a very useful document but it
  needs at least one more iteration.

- Philip Hallam-Baker: The drafts and presentations should be careful not to
  equate transmission security with cryptography in general. QKD provides
  transmission security (encryption of data in flight); it does not provide a
  solution for encryption of data at rest. Presenting QKD as a general solution
  for Shor's attack on PKI is not appropriate. Not being able to protect data
  at rest for 30+ years is the scariest part of Shor. There are also other
  solutions, e.g. Kerberos is quantum resistant and Philip Hallam-Baker's work
  on "Threshold Key Infrastructure" (a generalization of PKI for data at rest).
  Rodney van Meter: Which specific parts of the draft need to be changed?
  Philip Hallam-Baker: The security section.

- Philip Hallam-Baker: Also concerned about the traffic analysis point raised
  during the Q&A after Josh Slater's presentation.

(5) Status and recent updates on the principles draft, presented by Wojciech
Kozlowski
--------------------------------------------------------------------------------------

- "Architectural Principles for a Quantum Internet" draft at
  https://www.ietf.org/archive/id/draft-irtf-qirg-principles-05.txt

- Presentation slides at
  https://datatracker.ietf.org/meeting/109/materials/slides-109-qirg-draft-irtf-qirg-principles-00

- Questions and comments:

- Wojciech Kozlowski: Is the draft ready for QIRG last call? Rodney van Meter:
  I submitted a list of comments in February; have all been addressed? Wojciech
  Kozlowski: kept track of each individual issue on the mailing list and
  believes all have been addressed. Rodney van Meter: Has a discussion on 1st,
  2nd, and 3rd generation networks been added? Wojciech Kozlowski: Yes, in the
  error management section (4.4.3). Rodney van Meter: Before last call, we need
  to read both drafts in parallel, and make sure they agree on terminology etc.
  Wojciech Kozlowski: we need to be alignment on the control plane in both
  drafts. Rodney van Meter: would like one more end-to-end parallel reading
  before signing off on last call (as author and chair). Wojciech Kozlowski:
  Let's keep question of last call for the mailing list.

- Rodney van Meter: how many people have read the draft recently (say version 4
  or 5). The "show of hands tool" shows 12 raised hands, 6 not raised, 51
  participants. 2 comments in the chat explicitly liked the draft and found it
  useful. Conclusion: decent number of people have had good read. Would like to
  initiate last call in the next couple of weeks, contingent on more round of
  reading.

(6) Open mic questions and discussion
-------------------------------------

Colin Perkins: Are prototyping and experimental implementations part of the
next steps? Wojciech Kozlowski and Josh Slater: The work that is being done in
QuTech on building the first quantum Internet has indeed taken inspiration from
the QIRG work. The first network link is planned to be online in 2021. Next
year it will be upgraded to include quantum repeaters. A recent paper on the
quantum internet network layer protocol (https://arxiv.org/abs/2010.02575) is
specifically inspired on QIRG discussions. A paper on the quantum internet
datalink layer (https://arxiv.org/abs/1903.09778) was already published
earlier. There is a plan to publish the Quantum Network Experience (QNE) which
will be a web-based front-end to run quantum distributed applications on the
first prototype quantum network.

Rodney van Meter: Can you clarify whether the MDI QKD node needs to be trusted
or not? I suppose it depends on how you define a "node"; in the context of
quantum network architecture we went back and forth on the question whether a
Bell state measurement middle-point should count as a separate node or as part
of the link (the initial inclination was the latter). Bruno Rijsman: In the
case of MDI QKD the middle node facilitates star shaped topologies, so it also
includes (for example) MEMS cross-connects; it is more than just a BSM. Rodney
van Meter: This is also applies to networks that create graph entangled states.
Josh Slater: I feel that the midpoints / center nodes should be an active
participant if it's acting to bring point-to-multi-point functionality.
Wojciech Kozlowski: a useful analogy with classical networks may be to compare
BSM midpoints with layer-2 local area networks, and true quantum repeaters /
quantum routers with layer-3 wide area networks. Agrees that the midpoint can
be an active element.

Kireeti Kompella: Can one cascade midpoints? Bruno Rijsman: For MDI QKD
networks, if there is a single midpoint it can be untrusted. For multi-hop MDI
QKD networks (a series of >= 2 midpoints) one needs either quantum repeaters or
trusted midpoints.

Josh Slater: The Chinese QKD network is long chain of "super nodes" which are
trusted, each midpoint has its own star network around it. The USA Quantum
Xchange network between NY and New Jersey will have a similar topology. This
supports the case for viewing midpoints as separate active nodes.

Joey Salazar: Does QKD provide anonymity? In other words, can the users that
exchange keys be identified / tracked? Wojciech Kozlowski: No, QKD is currently
not anonymous. Anonymity is difficult to guarantee for QKD, but may be possible
for other applications.

Rodney van Meter: What is the process for finalizing the draft? The group and
chairs conclude is work is done and submit it. The IRSG will review, check for
conflicts with IETF, and provide feedback. Most likely there will be comments.
Then gets published as RFC.