From: "Raystonn ." <raystonn@hotmail•com>
To: "Peter Todd" <pete@petertodd•org>
Cc: Bitcoin Dev <bitcoin-development@lists•sourceforge.net>,
"Patrick Mccorry \(PGR\)" <patrick.mccorry@newcastle•ac.uk>
Subject: Re: [Bitcoin-development] New attack identified and potential solution described: Dropped-transaction spam attack against the blocksize limit
Date: Mon, 8 Jun 2015 15:01:34 -0700 [thread overview]
Message-ID: <COL131-DS52C1B18F4EFC4D7D7EEA1CDBF0@phx.gbl> (raw)
In-Reply-To: <20150608214443.GC19826@muck>
> There will always be a blocksize limit based on technological
> considerations - the network has a finite bandwidth limit.
A bandwidth limit is not the same as a blocksize limit. Bandwidth is unique
to every individual. Miners in China have different bandwidth and
connectivity than miners in the U.S., for example. But the block size limit
is dictated for eveyone. They are not comparable.
> Without a blocksize limit the attacker would just flood the network until
> the bandwidth usage became so great that consensus would fail, rendering
> Bitcoin both worthless, and insecure.
No, with no blocksize limit, a spammer would would flood the network with
transactions until they ran out of money. Meanwhile, everyone would jump on
board trying to mine the blocks to collect the fees from the spammers. It
could be one of the greatest transfers of wealth ever. Bitcoin
infrastructure would build up to handle the required bandwidth, paid for by
the very entity spamming the network. Bitcoin would flourish, growing
wildly as long as the fees kept coming. This is antifragility at its best.
> The worst an attacker flooding the network with transactions with a
> blocksize limit can do is raise costs, without harming security.
No, at attacker flooding the network with transactions with a blocksize
limit can keep their fees high enough that perhaps 1% of transactions coming
from real end-users go through. At this point everyone would give up on
Bitcoin as it would become completely unusable. The BTCUSD market would
tank, making it even easier to pay the transaction fees to keep real
transactions out of blocks, as it would continue to become cheaper and
eventually cost-free to obtain the bitcoin fees through market purchase.
-----Original Message-----
From: Peter Todd
Sent: Monday, June 08, 2015 2:44 PM
To: Raystonn .
Cc: Patrick Mccorry (PGR) ; Bitcoin Dev
Subject: Re: [Bitcoin-development] New attack identified and potential
solution described: Dropped-transaction spam attack against the blocksize
limit
On Mon, Jun 08, 2015 at 02:33:54PM -0700, Raystonn . wrote:
> > the attack would be expensive.
>
> For attacks being waged to destroy Bitcoin by filling all blocks with spam
> transactions, the attack succeeds when the attacker is well funded. This
> gives well-funded private and/or public entities the means to destroy
> Bitcoin if they desire. This is only true after the block size limit was
> implemented. Without the block size limit, the spam doesn’t harm Bitcoin.
> It simply enriches miners at the cost of the spammers, which is a nicely
> antifragile quality.
There will always be a blocksize limit based on technological
considerations - the network has a finite bandwidth limit.
Without a blocksize limit the attacker would just flood the network until
the bandwidth usage became so great that consensus would fail, rendering
Bitcoin both worthless, and insecure.
The worst an attacker flooding the network with transactions with a
blocksize limit can do is raise costs, without harming security. Keep in
mind, that at some point it'd be cheaper to just 51% attack the network.
Based on the current block subsidy of 25BTC/MB that's at the point where
transaction fees are 25mBTC/KB, which corresponds to <$2/tx fees - not that
cheap, but still quite affordable for a large percentage of Bitcoin's users
right now. And that's the *absolute worst-case* attack possible.
next prev parent reply other threads:[~2015-06-08 22:01 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-08 0:36 [Bitcoin-development] Block Size Experiment Underway Tom Harding
2015-06-08 20:07 ` [Bitcoin-development] New attack identified and potential solution described: Dropped-transaction spam attack against the block size limit Raystonn .
[not found] ` <AD4A025F-D782-4094-9CBC-EBEF0DD04838@newcastle.ac.uk>
2015-06-08 21:14 ` Raystonn .
2015-06-08 21:33 ` Peter Todd
2015-06-08 21:40 ` [Bitcoin-development] New attack identified and potential solution described: Dropped-transaction spam attack against the blocksize limit Raystonn .
[not found] ` <4A74E0B9-869E-448A-BFC7-7FD2F50F142F@newcastle.ac.uk>
2015-06-08 22:26 ` [Bitcoin-development] New attack identified and potential solution described: Dropped-transaction spam attack against the block size limit Peter Todd
[not found] ` <7E7DF414-6DDB-48A6-9199-D6883209B67D@newcastle.ac.uk>
2015-06-08 21:33 ` Raystonn .
2015-06-08 21:44 ` Peter Todd
2015-06-08 22:01 ` Raystonn . [this message]
2015-06-08 22:07 ` [Bitcoin-development] New attack identified and potential solution described: Dropped-transaction spam attack against the blocksize limit Btc Drak
2015-06-08 22:10 ` Raystonn .
2015-06-08 22:18 ` Peter Todd
2015-06-08 22:46 ` Raystonn .
2015-06-08 22:06 ` [Bitcoin-development] New attack identified and potential solution described: Dropped-transaction spam attack against the block size limit Bob McElrath
2015-06-08 22:28 ` Peter Todd
2015-06-09 9:33 ` Loi Luu
2015-06-09 13:36 ` Gavin Andresen
2015-06-09 14:18 ` Tier Nolan
2015-06-09 17:52 ` Raystonn .
2015-06-09 18:25 ` Gavin Andresen
2015-06-09 19:03 ` Raystonn .
2015-06-20 3:49 ` David Vorick
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=COL131-DS52C1B18F4EFC4D7D7EEA1CDBF0@phx.gbl \
--to=raystonn@hotmail$(echo .)com \
--cc=bitcoin-development@lists$(echo .)sourceforge.net \
--cc=patrick.mccorry@newcastle$(echo .)ac.uk \
--cc=pete@petertodd$(echo .)org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox