Design a price advertisement protocol

[s-tikhomirov]

Price advertisement is one of the two (not mutually exclusive) ways for Store servers to share their price offers with clients.

Another one is price negotiation - see #52.

Under a price advertisement protocol, a server publicly announces its price policy. Possible media for price ads include:

• a special (pubsub? content?) topic in the Waku network;
• a blockchain (e.g., via Ethereum's CALLDATA or EIP-4844 blobs)
• another messaging protocol (e.g., IRC)
• a centralized website (security evaluation required).

Outdated prices may be an issue. The maximum frequency of price updates depends on the medium, but it's unlikely that doing updates, say, multiple times per second would be feasible (evaluation required).

See also: Lightning Network's liquidity ads.

[fryorcraken]

a req-res protocol could also be used. Not saying it should but I'd include that in the list of possibilities. It could happen as soon as one connects to a store server or maybe as part of some initial req-res (e.g requesting stored msg ids)