Protocol version 7 update proposal

[td202]

Purpose

Define the specification for the protocol version 7 update.

Changes

• Introduce P7 update.

Checklist

• My code follows the style of this project.
• The code compiles without warnings.
• I have performed a self-review of the changes.
• I have documented my code, in particular the intent of the
  hard-to-understand areas.
• (If necessary) I have updated the CHANGELOG.

[DOBEN]

Well done.

[Victor-N-Suadicani]

Various suggestions (and only suggestions, I don't yet have the competences to truly question anything in this document).

General question: Any reason why these protocol updates aren't using Markdown? It'd be easier to read/format them (especially here on GitHub) and it'd be simple to insert images like diagrams and such.

[limemloh]

We also change the hashing structure of the block hash preparing for a light client as part of this protocol update, right?

[eb-concordium]

Looks good to me

[limemloh]

@Victor-N-Suadicani

General question: Any reason why these protocol updates aren't using Markdown? It'd be easier to read/format them (especially here on GitHub) and it'd be simple to insert images like diagrams and such.

This specification needs to be hashed and signed as part of the protocol chain update. We could have used markdown, but it makes the hashing of the document a bit more complex with external resources and so on.
It also leaves out the issue of how to display markdown, with txt there is not really any doubt.

[Victor-N-Suadicani]

I would say you could just as easily hash the Markdown file itself, just as a .txt file, excluding any external things linked (like images), which could be considered non-normative. Markdown looks pretty similar regardless of what you use to render it and as mentioned GitHub automatically lets you see the rendered Markdown and we use GitHub so... just kinda makes sense to me 😅. Anyways, I won't press this further if it is not desirable.

[chportma]

I caught 3 instances of baker instead of validator. Apart from that, my only other comment is what I posted in slack: should we be mentioning here the cool-down time changes that we will do and undo when updating the protocol?