I am looking for some sort of communication or consensus algorithm with the following properties:
- Can be used with just two parties (and ideally doesn't collapse to a trivial case with two parties)
- Requires each party to initiate some sort of communication to which the other responds (ideally in a binary way)
- Bonus points if it's some sort of consensus, decision-making, or contract signing algorithm
Context: my boyfriend and I are planning on getting engaged soon. For various reasons, we would both like to propose to each other. The challenge is that we don't want whichever proposal is second to feel like it was unnecessary. Since we're both computer scientists, we figure there must be an algorithmic solution to this problem! So we are looking for a communication protocol/consensus algorithm/something else in that vein in which it is necessary for both parties to initiate and respond to a communication. We will be implementing the chosen algorithm verbally, not over an actual internet connection. In case you're having a hard time picturing this, it would be kind of like how a lot of textbooks will have conversational English versions of the messages being sent under various communications protocols, e.g.:
Except we would replace "Hey. Can I talk to you?" with something more like "Will you marry me?".
Before anyone asks, yes, this is entirely symbolic/for fun, but we feel that's true of most aspects of getting engaged/married. And yes, we are nerdy enough that we will happily exchange random numbers with each other in public if that's what the protocol (or its associated cryptography) demands.
Possibilities we've considered so far:
- TCP: This was our first thought, but it's not a great fit. For connection establishment all the server sends is a SYN-ACK, which isn't really satisfying either as a response to the first proposal or as the question being asked in the second proposal. The connection termination protocol seems like it would be weird to adapt to verbal communication.
- Dining cryptographers: Would be great (although we'd have to use 0 to mean yes, which is a little gross), except it falls apart with only two parties. So we'd have to include a third person (and give them veto power over our engagement). It would be perfect for a polyamorous engagement, though!
- Some sort of blockchain consensus algorithm: All the ones I'm aware of seem like they'd collapse to a trivial case with two parties (but I could be wrong about this)
- Some sort of contract signing algorithm: Probably the best option we've found so far. These are the closest to being designed to solve the actual problem that we have, but all the ones I've seen require some sort of trusted third party (we could make that work but it wouldn't be ideal).
Does anyone know of an algorithm that is a better fit than these? Apologies if this is off-topic (I'm hoping it falls under "we do not hate fun")!