Instead of thinking in terms of blocking uneconomical transactions (how would a node even determine what's economical?), what about thinking in terms of paying for a feed of economical (i.e. profitable) transactions? There is a market for fee bearing, profitable transactions...if there is no one willing to pay to receive a transaction, then no one will bother propagating it. Such a system would make it possible to determine the probability of confirmation in a given timeframe for a given fee. On Tue, Mar 12, 2013 at 3:49 AM, Peter Todd wrote: > On Sat, Mar 09, 2013 at 11:31:55PM -0500, Peter Todd wrote: > > As discussed endlessly data in the UTXO set is more costly, especially > > in the long run, than transaction data itself. The fee system is per KB > > in a block, and thus doesn't properly capture the long-term costs of > > UTXO creation. > > There's been a lot of discussion about this issue, and many people have > asked that Bitcoin not arbitrarily block interesting potential uses of > provably unspendable txouts for data applications, and similarly > spendable txouts representing assets. I've changed my hardline position > and now think we should support all that stuff. However, there is one > remaining class of txout not yet talked about, unspendable but not > provably so txouts. For instance we could make the following a standard > transaction type: > > scriptPubKey: OP_HASH160 <20 byte digest> OP_EQUALVERIFY > scriptSig: > > Of course, usually the 20 byte digest would be picked randomly, but it > might not be, and thus all validating nodes will always have a copy of > the data. With the 10KB limit on script sizes you can fit 9974 bytes of > data per transaction output with very little waste. > > A good application is timestamping, with the advantage over > coinbase/merkle tree systems in that you don't have to wait until your > timestamp confirms, or even store the timestamp at all. Another > application, quite possible with large block sizes and hence cheap or > free transactions, is secure data backups. In particular such a service, > perhaps called Google Chain Storage, can offer the unique guarantee that > you can know you're data is secure by simply performing a successful > Bitcoin transaction. > > -- > 'peter'[:-1]@petertodd.org > > > ------------------------------------------------------------------------------ > Symantec Endpoint Protection 12 positioned as A LEADER in The Forrester > Wave(TM): Endpoint Security, Q1 2013 and "remains a good choice" in the > endpoint security space. For insight on selecting the right partner to > tackle endpoint security challenges, access the full report. > http://p.sf.net/sfu/symantec-dev2dev > _______________________________________________ > Bitcoin-development mailing list > Bitcoin-development@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/bitcoin-development > > -- Stephen Pair, Co-Founder, CTO Does *your* website accept cash? bitpay.com [image: bitpay-small] ABC6 C11B BF75 9E2B FC6A B3E0 7B96 40B2 CAC0 C158