Sending messages with transactions

[Gareth Nelson]

There's a simple way to do this without taking up space in the blockchain.
Simply send the transaction ID and your message to an external server, encrypt if desired.

This could be integrated with the client rather easily, but i'm wondering how many would actually use it - thoughts?

[FooDSt4mP]

There's a simple way to do this without taking up space in the blockchain.
Simply send the transaction ID and your message to an external server, encrypt if desired.

This could be integrated with the client rather easily, but i'm wondering how many would actually use it - thoughts?

I doubt you'd get support from the official client unless the "external server" was actually a distributed network.  Also, it should be encrypted with the public key the coins were sent to (the address).  The recipient has the matching private key to decrypt it.

[Gareth Nelson]

I obviously wouldn't expect the official client to rely on an external server (although oddly enough it still relies on IRC) - but this does seem a sensible idea.

[FooDSt4mP]

I obviously wouldn't expect the official client to rely on an external server (although oddly enough it still relies on IRC) - but this does seem a sensible idea.

It doesn't rely on IRC... IRC just helps it bootstrap faster when it is available.  There is a list of fallback nodes (in addition to those built into the client) and -addnode.

Regarding messages: you should probably also require the message be signed by at least one private key matching one of the public keys the transaction is sent from.  Otherwise, messages could be forged.