node types: storage nodes

[liamsi]

Partial nodes map to storage nodes in the original paper. IMO, the specification should mention this fact but independently of the original paper the specification should also mention the role of storage nodes for the p2p network.

Action Items

So additionally to just:

• mentioning storage nodes (Note that partial nodes can act as storage nodes for subset of blocks #177)

This issue is also about the critical (?) role storage nodes might or might not play in the overall. system

Particularly if there any assumptions made about:

• the number of storage nodes
• the amount of data these need to store
• and liveness or security implications if the above assumptions are not met
• assumed number of storage nodes that other nodes-types are expected to connect to
• any other high-level networking assumptions related to storage nodes

When above is clarified this should also yield concrete recommendations:

• what data to store, how much of it and for how long

Clarify if still want to specify a public API for storage nodes:

• Storage node & protocol #3

These need to be specified as well. I would suggest to open separate issues for the subtasks and link them here.