Plasma Front Running problem

[MihailoBjelic]

@gakonst

This is not a vulnerability for people who challenge exits of their own coins. They may miss out on collecting the bond, and pay the gas fees, but what they actually care about is the safety of their coin which is preserved.

This is only true if the nominal value of coins is substantial. One possible situation here: a user tries to prevent a malicious exit of her coins and ends up with a net loss (the gas paid is more valuable than the coins, but she planned to take the bond, too).

@gakonst

It can be solved by integrating a Submarine commit/reveal scheme so that it does not leak any information. Take a look at libsubmarine.org.

I like LibSubmarine but it introduces additional complexity (on top of all existing Plasma complexity ) and it has its own challenges (like any commit/reveal scheme).

@gakonst

It should also be noted that this is a general issue of any game which relies on bonded challenges on a chain which is controlled by miners, such as payment/state channels as well.

Absolutely, bonded challenges are a huge challenge.

@gakonst

This is a non-issue with very low priority imho

Not sure.

@gakonst

solve how to do non-grievable watchtowers

Any resources/thoughts? I’m very pessimistic when it comes to this, except in cases when “watchtowers” are essentially a fully formalized, large pool of bonded entities with programmed behavior (similar to Polkadot and Eth 2.0 validators). Even then it’s a huge challenge to reshuffle them, and if you decide to permanently assign them to a set of users/chains, we all know what can happen after some time…

@gakonst

will only manifest after we see these watchtowers gain adoption so that frontrunners even bother attacking them

Frontrunners don’t care who they’re frontrunning (users or watchtowers), it’s the same for them, so this problem will manifest immediately (if it manifests at all).