Thread by @murchandamus

@giacomozucco @CarstenBKK @BlueDelta0 @StopAndDecrypt Alright, so our threat model is a widespread effort to change the protocol rules with support of a majority hashing attack. Presumably this is incompatible with existing network rules as enforced by fully validating nodes, but compatible with thin clients.

@giacomozucco @CarstenBKK @BlueDelta0 @StopAndDecrypt a) A vast majority of FN oppose this protocol change. Attackers are banned by their peers, blocks don't propagate, most thin clients never see the blocks. Affected scrutinizing thin client discovers changed rules when first valid block is found, if it has at least 1 honest peer.

@giacomozucco @CarstenBKK @BlueDelta0 @StopAndDecrypt b) Significant count of FN support protocol change. FN topology decouples, some Scrutinizing Thin Clients (STC) are eclipsed by attack. STC will at the latest fully validate the first block that includes any transaction that concerns them. 1) Discovers invalid block if rule...

@giacomozucco @CarstenBKK @BlueDelta0 @StopAndDecrypt that can be checked on individual block is broken (e.g. block weight, difficulty, many hard forks, changed signing scheme). 2) Assuming block passes scrutiny, will only accept the payment after multiple confirmations. Def options: BIP150/BIP151 paired FN, only small amounts, news

@giacomozucco @CarstenBKK @BlueDelta0 @StopAndDecrypt c) Majority attack protocol change is supported by vast majority of FN and economic majority. 1) Possibly many eclipsed/disconnected honest FN, broad intervention by principled Bitcoin supporters is necessary to reestablish working network, maybe even mining update required.

@giacomozucco @CarstenBKK @BlueDelta0 @StopAndDecrypt STC generally unsafe, possibly even 2) Bitcoin experiment considered failed altogether by principled Bitcoin supporters.

@giacomozucco @CarstenBKK @BlueDelta0 @StopAndDecrypt Meh, this is reaching the point where Twitter as a medium is just insufficient. Generally, broad use of STC requires a healthy FN population. STC users are incentivized to run their own FN to ensure honest peer. STC users may pay for more FN to ensure peer service availability.

@giacomozucco @CarstenBKK @BlueDelta0 @StopAndDecrypt Or like with many other IT services, STC may cluster around token nerd family member/acquaintance that provides FN peer service for social recognition or on principle.
STC-only network probably equates tragedy of commons and is unlikely to result in stable network.

@giacomozucco @CarstenBKK @BlueDelta0 @StopAndDecrypt Altogether, I just have a hard time being worried about a skewed balance towards too many thin clients as there are self-balancing feedback loops, economic actors that must run FN and principled actors that run FN by conviction.

@giacomozucco @CarstenBKK @BlueDelta0 @StopAndDecrypt Deliberately sabotaging possible development of STC is imho a premature optimization that restricts possible future mass adoption scenarios that are compatible with principled development of base layer protocol evolution.