# Gavin Andresen
# 2011-08-12 13:43:48
# https://bitcointalk.org/index.php?topic=35382.msg451174#msg451174

Half-baked thoughts on transaction relaying (I agree that it may become a major problem because there are no incentives to properly relay transactions right now): @p{par}

I think writing code to reliably detect that a peer isn't relaying transactions is possible. Something like: @p{brk}
 Generating a new transaction: @p{brk}
  Pick a connected peer at random "P" @p{brk}
  Relay new transaction to all nodes EXCEPT P @p{brk}
  If, after a little while, P doesn't tell us about our new transaction then it is likely P is not relaying properly. @p{brk}
   (assumption is that we are not P's only connection, and it will get the transaction from its other peers) @p{par}

And I think something like the above could be one of the metrics used to measure "ill-behaving peers" (other metrics might be number of double-spend transactions or orphan blocks received, number of spammy-looking transactions received, etc).  If a peer is too ill-behaved, the penalty could be shunning@p{--} drop its connection and add its IP to a temporary refuse-connections list. @p{par}

(maybe lesser penalties make sense, too@p{--} maybe order-of-relaying is based on good behavior, so the code announces new blocks/transactions to better-behaved peers fore worse-behaved peers). @p{par}

If cheating miners find themselves disconnected from the rest of the network, that is a strong incentive not to cheat. @p{par}

I'd really like somebody with a lot more network design experience than me to run some simulations and see what network behavior would be like with/without rules like I'm proposing.  Or tell me that disconnecting ill-behaving nodes is a terrible idea because it makes it easy for an attacker to shatter the network into a gazillion pieces... @p{brk}