Anapaya review

[nicorusti]

Following the first wave of ISE feedback, we did quite some work, especially on the control plane draft:

Please review (sorted by urgency):

• mtu: add clarifications. #63
• 2.3.3. Effects of Clock Inaccuracy
• 2.4. Path Discovery Time and Scalability
• 5. Security Considerations
• Control Service gRPC API (appendix)

Other pointers:

• Changelog
• Datatracker diff v-03 to main

@shitz @oncilla @sgmonroy could one of you have a look at the overall changes and provide some feedback? If you feel, you can directly open a PR. We are planning to have a new submission when datatracker reopens on 21.07, before our panrg session to address #48 , and it would be great if we could also incorporate some of your feedback.

[oncilla]

The expiration of a SCION AS certificate typically ranges from
3h to 5 years.

Where does this number come from. Most typically it is 3days, and in some very special cases we have 5 days.
I have never seen 5 years outside of some private ISDs

[oncilla]

Once
this number grows above the maximum recommended best PCBs set size of
50,

Where does this number come from?
Default is 20. AFAIK:
https://github.com/scionproto/scion/blob/aa917bb458d6675efc55b4a23fda2c694094553e/control/beacon/policy.go#L43

[nicorusti]

The expiration of a SCION AS certificate typically ranges from
3h to 5 years.

Where does this number come from. Most typically it is 3days, and in some very special cases we have 5 days. I have never seen 5 years outside of some private ISDs

This comes from 297e8d2 @jiceatscion do you have more background?

@oncilla you're right, in the PKI draft we write The RECOMMENDED maximum validity period of a CP AS certificate is: 3 days. I don't think, however, we set an upper bound to the validity.

I see two action items:

• Correct CP draft to say "3h to 5 days".
• Shall we set an upper bound for validity in the PKI draft? Or alternatively say that validity may be up to 5 days instead of 3?

[nicorusti]

The comes from the first version of the draft: b652927

Once
this number grows above the maximum recommended best PCBs set size of
50,

Where does this number come from? Default is 20. AFAIK: https://github.com/scionproto/scion/blob/aa917bb458d6675efc55b4a23fda2c694094553e/control/beacon/policy.go#L43

It comes from the initial version of the draft:
b652927
I could not find where this comes from

@jiceatscion I'd skim through #46 that has some considerations from ETH on beaconing

[jiceatscion]

Once
this number grows above the maximum recommended best PCBs set size of
50,

Where does this number come from? Default is 20. AFAIK: https://github.com/scionproto/scion/blob/aa917bb458d6675efc55b4a23fda2c694094553e/control/beacon/policy.go#L43

These numbers aren't described as recommended values, but as recommended maxima. It came from some back-of-the-envelope calculations made by Matthias and used as worst-case examples in the scalability/Intra-ISD Beaconing section.

The code says the default is 20, but then, that isn't a recommended value, just a mechanical place holder: it is 20 even for a core AS (if I managed to follow the code), which, wouldn't be such a good idea, would it?

I'll try and clarify that notion in the text.

[jiceatscion]

The expiration of a SCION AS certificate typically ranges from
3h to 5 years.

Where does this number come from. Most typically it is 3days, and in some very special cases we have 5 days. I have never seen 5 years outside of some private ISDs

I have no recollection. In all likeliness I was looking for the maximum range ever used and someone must have mentioned the existence the 5y case. If that is such an outlier, I can change the text to emphasize what the reasonable range is.

[jiceatscion]

The expiration of a SCION AS certificate typically ranges from
3h to 5 years.

Where does this number come from. Most typically it is 3days, and in some very special cases we have 5 days. I have never seen 5 years outside of some private ISDs

This comes from 297e8d2 @jiceatscion do you have more background?

@oncilla you're right, in the PKI draft we write The RECOMMENDED maximum validity period of a CP AS certificate is: 3 days. I don't think, however, we set an upper bound to the validity.

I see two action items:

* [ ]  Correct CP draft to say "3h to 5 _days_".

* [ ]  Shall we set an upper bound for validity in the PKI draft? Or alternatively say that validity may be up to 5 days instead of 3?

As usual, I can take a Jesuitic approach and make a distinction between common and recommended. That way we leave the pki draft and its recommendation of 3 days alone. In the cp draft I will made the same recommendation and mention 5 days as an outlier. Let's forget the 5y.